https://galileospendulum.org/2025/06/05/open-letter-to-anti-trans-science-journalists/2025-06-05T12:24:32+00:00monthlyhttps://galileospendulum.org/2024/12/17/goodbye-bluesky/https://galileospendulum.org/wp-content/uploads/2024/12/alf-bluesky.jpgalf bluesky2024-12-18T13:44:23+00:00monthlyhttps://galileospendulum.org/2023/08/14/twitter-is-dead-and-i-dont-feel-so-good-myself/2023-08-14T18:40:41+00:00monthlyhttps://galileospendulum.org/2023/02/26/what-is-life/https://galileospendulum.org/wp-content/uploads/2023/02/lake2.jpgOLYMPUS DIGITAL CAMERAOLYMPUS DIGITAL CAMERAhttps://galileospendulum.org/wp-content/uploads/2023/02/trailer.jpgOLYMPUS DIGITAL CAMERAOLYMPUS DIGITAL CAMERAhttps://galileospendulum.org/wp-content/uploads/2023/02/rover.jpgOLYMPUS DIGITAL CAMERAOLYMPUS DIGITAL CAMERAhttps://galileospendulum.org/wp-content/uploads/2023/02/lake1.jpgOLYMPUS DIGITAL CAMERAOLYMPUS DIGITAL CAMERAhttps://galileospendulum.org/wp-content/uploads/2023/02/microbialites.jpgmicrobialites2023-02-26T16:14:40+00:00monthlyhttps://galileospendulum.org/2023/02/03/new-comics-anthology-failure-to-launch/https://galileospendulum.org/wp-content/uploads/2023/02/windpower-banner.pngwindpower-banner2023-02-06T17:46:10+00:00monthlyhttps://galileospendulum.org/2020/11/04/the-stone-child/2023-02-03T19:03:23+00:00monthlyhttps://galileospendulum.org/2022/07/11/why-i-will-not-write-about-jwst/https://galileospendulum.org/wp-content/uploads/2022/07/nasa-lego-collection.jpgnasa-lego-collection2022-12-14T15:49:16+00:00monthlyhttps://galileospendulum.org/2021/05/07/the-lavender-scare-and-a-tangled-webb/2021-05-09T01:59:33+00:00monthlyhttps://galileospendulum.org/2019/07/12/im-publishing-a-book-and-you-can-help-it-happen/https://galileospendulum.org/wp-content/uploads/2019/07/whoownsanasteroid_smallcover.pngWhoOwnsAnAsteroid_smallcoverpreliminary copy design for "Who Owns an Asteroid?", a comics collection by Maki Naro and me.2019-07-12T14:46:29+00:00monthlyhttps://galileospendulum.org/2018/04/10/iq-skepticism-and-the-failure-of-debate/https://galileospendulum.org/wp-content/uploads/2018/04/yglesias-murray-chopper-meme.jpgOrange County Choppers memeShould I even try to explain this Twitter meme in a figure caption? No, I should not. Click for the original. [Source/credit: Matt Yglesias, https://twitter.com/mattyglesias/status/983398900190138369 ]2018-04-11T16:17:46+00:00monthlyhttps://galileospendulum.org/2017/03/29/using-science-to-imagine-a-fantasy-world/https://galileospendulum.org/wp-content/uploads/2017/03/habitable-zone.pngHabitable ZoneThe habitable zone for the twinsuns is the region marked in green. The blue region is too cold for surface liquid water, and the red zone is too hot. The dotted line represents the orbit of Sambke. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2017/03/received-light1.pngreceived lightVariation in the amount of light Sambke receives over the course of a suncycle. The first half of the curve is when Redsun is closer to Sambke than Yellowsun, while the second half is when Yellowsun is closer. The two downward spikes show when Redsun eclipses Yellowsun and vice-versa. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2017/03/received-light.pngreceived lightVariation in the amount of light Sambke receives over the course of a suncycle. The first half of the curve is when Redsun is closer to Sambke than Yellowsun, while the second half is when Yellowsun is closer. The two downward spikes show when Redsun eclipses Yellowsun and vice-versa. [Credit: moi] https://galileospendulum.org/wp-content/uploads/2017/03/polar.giforbit animationAnimation of one year: one complete orbit of Sambke around the twinsuns. Since the suns themselves orbit, this animation shows how sunrises and sunsets vary over the course of a year. The orbits are to scale, but the sizes of the suns and planet are not. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2017/03/sambke_diagram.pngThe orbit of Sambke around its twin sunsThe imaginary planet Sambke orbits two suns, which orbit their mutual center of mass (marked by the white dot, which is empty space). The size of the orbits are to scale, but the size of the suns and planet are not. [Credit: moi]2017-11-22T08:20:40+00:00monthlyhttps://galileospendulum.org/2017/10/20/why-set-a-fantasy-novel-on-another-planet/https://galileospendulum.org/wp-content/uploads/2017/10/giant_floating_head_of_doom.jpgyouthful drawing of a giant floating monster headArt from a very early fantasy story I wrote. My art hasn't improved much, but I hope my writing has. [Credit: 8-year-old moi]2017-10-20T14:21:26+00:00monthlyhttps://galileospendulum.org/2017/10/10/all-musicians-are-subconsciously-mathematicians/https://galileospendulum.org/wp-content/uploads/2017/10/monk-and-company.jpgMonk and companyThelonious Monk (left) with Howard McGhee, Roy Eldridge, and Teddy Hill in 1947. Unfortunately most photos of Monk are still under copyright and not free to use, but if you look around the web, you can see lots of pictures of Monk and his sense of style. [Credit: William Gottlieb]2017-10-12T16:12:57+00:00monthlyhttps://galileospendulum.org/2017/01/02/2017-onward-and-upward/2017-01-02T22:04:13+00:00monthlyhttps://galileospendulum.org/2016/12/22/spend-your-winter-on-mars-and-the-outer-solar-system/2016-12-21T19:23:07+00:00monthlyhttps://galileospendulum.org/2016/12/19/science-is-and-always-has-been-political/https://galileospendulum.org/wp-content/uploads/2016/12/one-of-the-idiots.gifone-of-the-idiotsWhy American scientists should care about the political state of the nation.2016-12-19T18:31:04+00:00monthlyhttps://galileospendulum.org/2016/10/03/dethroning-the-nobel-prize/https://galileospendulum.org/wp-content/uploads/2016/10/033.jpgLIGOOne arm of the LIGO detector near Livingston, Louisiana. [Credit: moi]2016-10-03T13:47:50+00:00monthlyhttps://galileospendulum.org/2016/09/27/the-return-of-cosmoacademy/2016-10-10T14:09:45+00:00monthlyhttps://galileospendulum.org/2016/09/18/rocket-guitar-drums/https://galileospendulum.org/wp-content/uploads/2016/09/snorfler.jpgOSIRIS-REx sample armThe prototype of the snorfler, the business end of the sampling arm on OSIRIS-REx. This device will pump nitrogen gas into the dust and rock on the asteroid's surface and collect what gets dislodged for return to Earth. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2016/09/atlas-v-launch-web.jpgAtlas V rocket carrying OSIRIS-RExThe Atlas V rocket carrying the OSIRIS-REx mission toward asteroid Bennu. I went to Florida to watch the launch on September 8, 2016. And it was AWESOME. [Credit: moi]2016-09-18T18:28:04+00:00monthlyhttps://galileospendulum.org/2016/03/08/east-of-heden-my-first-science-fiction-novella/https://galileospendulum.org/wp-content/uploads/2016/03/east-of-heden-cover-small.pngEast of hEden coverCover art for "East of (h)Eden", my new science fiction novella. [Credit: original painting by Ed Veligursky (PD)]2016-03-11T13:31:18+00:00monthlyhttps://galileospendulum.org/2016/02/23/the-price-of-sympathy-with-the-harasser/https://galileospendulum.org/wp-content/uploads/2016/02/imperious-pascal.jpgimperious PascalIt's hard to illustrate a post like this, so here's my cat Pascal being imperious. Or hungry. One or the other.https://galileospendulum.org/wp-content/uploads/2016/02/5e144-ei2bharassment.jpg5e144-ei2bharassment2016-02-23T19:36:59+00:00monthlyhttps://galileospendulum.org/2016/01/13/coffee-black-holes-editors-and-beer-the-science-writing-life/https://galileospendulum.org/wp-content/uploads/2016/01/slide-13-getting-it-right-xkcd-online.pngxkcd's 10,000 rulexkcd's "lucky 10,000": rather than think of someone as ignorant, think of them as the lucky person to learn something new and awesome. [Credit: Randall Munroe. Click for the original comic]https://galileospendulum.org/wp-content/uploads/2016/01/slide-12-science-is-not-just-science-online.pngGeoff Marcy and the Thirty Meter TelescopeGeoff Marcy and the Thirty Meter Telescope: two instances where the misbehavior of scientists got in the way of the science...and hurt people.https://galileospendulum.org/wp-content/uploads/2016/01/slide-10-getting-it-wrong-online.pngsometimes you'll get it wrongSometimes you'll get it wrong. [Credit: Questionable Content by Jeph Jacques. Click for the original comic]https://galileospendulum.org/wp-content/uploads/2016/01/slide-9-dumbing-down-online.pngexpunge the phrase "dumbing down" from your vocabularyExpunge the phrase "dumbing down" from your vocabulary.https://galileospendulum.org/wp-content/uploads/2016/01/slide-7-making-transition-online.pngmaking the transition from academic science to freelance writingScientists have advantages and disadvantages when they become freelance writers. You must unlearn some of what you have learned.https://galileospendulum.org/wp-content/uploads/2016/01/slide-6-what-does-a-writer-do-online.pngwhat does Matthew do all day?Writing is only one part of what a freelance writer has to do. The rest is the business of working for yourself.https://galileospendulum.org/wp-content/uploads/2016/01/slide-5-overlapping-domains-online.pngVenn diagram: science communication, education, and journalismThis Venn diagram is not to scale, but is simply intended to show that science education, "communication" (vaguely defined), and journalism aren't exactly the same thing. Depending on the publication, they may want more or less of various aspects.https://galileospendulum.org/wp-content/uploads/2016/01/slide-4-freelance-science-writer-online.pngwhat is a freelance science writer?What is a freelance science writer? https://galileospendulum.org/wp-content/uploads/2016/01/slide-3-introduction-to-me-online.pngI am a full-time freelance science writerPortrait of a science writer in their natural element. Since the summer of 2011, I have been earning part or all of my income from writing alone.https://galileospendulum.org/wp-content/uploads/2016/01/who-am-i-jackie-chan.jpgJackie Chan "Who Am I?" movie posterThe eminent philosopher-scientist Jackie Chan ponders: "who am I?" My answer follows.2016-01-26T20:44:08+00:00monthlyhttps://galileospendulum.org/2015/12/16/the-big-lie-of-social-justice/2015-12-18T16:41:24+00:00monthlyhttps://galileospendulum.org/2015/10/25/the-impostor-the-science-writer-and-terry-pratchett/2015-10-25T20:43:10+00:00monthlyhttps://galileospendulum.org/2015/10/13/things-i-tolerate-from-my-cats-that-i-never-would-at-a-conference/https://galileospendulum.org/wp-content/uploads/2015/10/pascal_and_harriet.jpgPascal and HarrietMy cats, Pascal and Harriet. [Credit: moi]2015-10-14T01:01:51+00:00monthlyhttps://galileospendulum.org/2015/10/07/why-i-missed-my-five-year-anniversary/2015-10-07T19:00:36+00:00monthlyhttps://galileospendulum.org/2015/07/05/the-redwings-left-today/https://galileospendulum.org/wp-content/uploads/2015/07/redwing-blackbird.jpgredwing blackbird[Credit: Alan D. Wilson, www.naturespicsonline.com]2015-07-05T21:08:18+00:00monthlyhttps://galileospendulum.org/2015/06/02/in-which-the-author-attempts-comics/https://galileospendulum.org/wp-content/uploads/2015/06/softer-world-tribute.pngor maybe one of those worlds will be entirely made of coffee2015-06-09T09:10:38+00:00monthlyhttps://galileospendulum.org/2015/05/18/relativity-and-relatives/https://galileospendulum.org/wp-content/uploads/2015/05/gravitation_shelfie.jpggravitational booksBooks on relativity and cosmology. [Credit: moi]2015-06-15T03:24:09+00:00monthlyhttps://galileospendulum.org/2015/05/04/you-know-what-leave-me-out-of-this/https://galileospendulum.org/wp-content/uploads/2015/05/james-brown-and-the-famous-flames-its-a-mans-mans-mans-world-polydor-international-2.jpgIt's a Man's Man's Man's WorldIt's a Man's Man's Man's World, at least if you look at who Williams and Ceci thought worthy of responding to.2015-05-05T13:01:15+00:00monthlyhttps://galileospendulum.org/2015/04/30/the-big-lie-of-science/2015-05-02T16:15:43+00:00monthlyhttps://galileospendulum.org/2015/04/21/a-study-in-how-not-to-talk-about-sexism-in-science/https://galileospendulum.org/wp-content/uploads/2015/04/zoidberg_study_is_bad.jpgZoidberg from Futurama[Credit: Futurama]2015-04-22T13:25:44+00:00monthlyhttps://galileospendulum.org/2015/04/04/science-by-authority-is-a-poor-model-for-communication/https://galileospendulum.org/wp-content/uploads/2015/04/ten_commandments.jpgCharleton Heston in "The Ten Commandments"Thirteen, wait, ten science books for every non-scientist to read and live by.2015-04-06T17:12:30+00:00monthlyhttps://galileospendulum.org/2015/04/01/want-to-live-chemical-free-try-doctor-bacfarcs-dark-matter-diet/https://galileospendulum.org/wp-content/uploads/2015/04/dark-matter-soup.jpgdark matter soupBacfarc's Dark Matter Soup™. Try it today!2015-04-01T18:29:57+00:00monthlyhttps://galileospendulum.org/2015/03/27/dear-senator-cruz-please-leave-galileo-out-of-it/2015-03-30T07:56:19+00:00monthlyhttps://galileospendulum.org/2015/02/17/come-to-the-dark-side-of-the-cosmos/https://galileospendulum.org/wp-content/uploads/2015/02/wmap_9year_pie.pngcosmic pieThe contents of the Universe are mostly dark matter and dark energy. [Credit: NASA / WMAP Science Team]https://galileospendulum.org/wp-content/uploads/2015/02/cosmoacademylogo-sq.pngCosmoAcademy logoWelcome to the newly rebooted CosmoAcademy!2015-02-20T06:14:42+00:00monthlyhttps://galileospendulum.org/2015/01/26/why-wormholes-probably-dont-exist/https://galileospendulum.org/wp-content/uploads/2015/01/sag_astar_orbits.jpgorbits of stars near the Milky Way's central black holeOrbits around the Milky Way’s central black hole, as obtained using the Keck telescope in Hawaii. [Credit: Keck/UCLA Galactic Center Group]2015-02-07T14:31:21+00:00monthlyhttps://galileospendulum.org/2015/01/30/the-right-road-to-scientific-revolution/https://galileospendulum.org/wp-content/uploads/2015/01/galileocentric.jpgGalileocentricReal revolutions happen on the dance floor. [Credit: Fake Science]2015-02-07T14:30:23+00:00monthlyhttps://galileospendulum.org/2015/02/02/some-thoughts-on-bicep2-and-dust/https://galileospendulum.org/wp-content/uploads/2015/02/planck_view_of_bicep2_field.pngvisualization of Planck data in the region of BICEP2Colorful visualization of Planck data in the region of BICEP2; click on the image for an even higher-resolution version. [Credit: ESA/Planck Collaboration/M.-A. Miville-Deschênes, CNRS – Institut d’Astrophysique Spatiale, Université Paris-XI, Orsay, France]2015-02-02T15:48:55+00:00monthlyhttps://galileospendulum.org/2015/01/07/two-new-classes-asteroids-and-gravity/https://galileospendulum.org/wp-content/uploads/2015/01/i-am-grote.pngI am GroteI (finally) just watched "Guardians of the Galaxy" the other night, and this was inevitable. For more on Grote Reber, click the image. [Credit: NRAO] 2015-01-08T13:57:28+00:00monthlyhttps://galileospendulum.org/2015/01/02/dont-bet-on-the-failure-of-relativity/https://galileospendulum.org/wp-content/uploads/2015/01/proving_einstein_wrong.pngEinstein was WRONG when he said that provisional patent #39561 represented a novel gravel-sorting technique and should be approved by the Patent Office.Yes, I've used this xkcd comic before. So sue me. [Credit: Randall Munroe. Click for the original.]2015-01-06T23:27:31+00:00monthlyhttps://galileospendulum.org/2014/12/17/the-case-of-the-disappearing-reappearing-martian-methane/https://galileospendulum.org/wp-content/uploads/2014/12/acme_ink.pngAcme Disappearing-Reappearing InkAcme Disappearing-Reappearing Ink, from "Who Framed Roger Rabbit?"2014-12-17T19:30:52+00:00monthlyhttps://galileospendulum.org/2014/12/15/what-would-you-like-to-learn-in-2015/https://galileospendulum.org/wp-content/uploads/2014/12/cosmoacademylogo-sq.pngCosmoAcademy logo2014-12-17T00:53:00+00:00monthlyhttps://galileospendulum.org/2014/12/14/comet-water-muddies-the-question-of-where-earths-oceans-came-from/https://galileospendulum.org/wp-content/uploads/2014/12/real_color_67p.jpgComet 67P as human eyes might see itRosetta image of Comet 67P, processed to give it the same color as human eyes might see it. (Most probes and telescopes filter light differently than our eyes.) Note that the comet is very dark gray, which is why comets in generally are known as "dirty snowballs". [Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA ]2014-12-15T15:27:15+00:00monthlyhttps://galileospendulum.org/2014/12/07/of-space-capsules-and-cookie-monsters/2014-12-07T15:02:51+00:00monthlyhttps://galileospendulum.org/2014/11/30/gravity-a-love-story/https://galileospendulum.org/wp-content/uploads/2014/11/me_at_nmsu.jpgspeaking at New Mexico State UniversityThe problem with claiming to know something is that people take you seriously sometimes. Here I am speaking at the astronomy department at New Mexico State University about science communication. [Credit: Meredith Rawls]2014-11-30T18:24:52+00:00monthlyhttps://galileospendulum.org/2014/11/24/black-holes-seem-to-know-their-place-in-the-cosmic-web/2014-11-24T18:21:47+00:00monthlyhttps://galileospendulum.org/2014/11/13/no-big-deal-we-just-landed-a-robot-on-a-comet/https://galileospendulum.org/wp-content/uploads/2014/11/philae_descent_image.pngPhilae descent imageComet 67P as seen by the Philae lander on its approach yesterday. [Credit: ESA/Rosetta/Philae/ROLIS]2014-11-25T20:46:37+00:00monthlyhttps://galileospendulum.org/2014/11/10/poems-in-the-heavens/https://galileospendulum.org/wp-content/uploads/2014/11/great_comet_of_1577.gifGreat Comet of 1577The Great Comet of 1577, from a contemporary woodcut by Jiri Daschitzsky. [Source: The Galileo Project]2014-11-12T07:53:20+00:00monthlyhttps://galileospendulum.org/2014/11/09/the-beauty-of-planetary-birth/https://galileospendulum.org/wp-content/uploads/2014/11/hltau_nrao.jpgprotoplanetary disk around HL TauriAn amazing view of the protoplanetary disk around the newborn star HL Tauri. The dark rings are places where new planets are forming, along with places where gravity from those planets causes ripples in the debris. [Credit: ALMA (NRAO/ESO/NAOJ); C. Brogan, B. Saxton (NRAO/AUI/NSF)]2014-11-09T15:51:42+00:00monthlyhttps://galileospendulum.org/2014/11/07/how-is-a-proton-like-a-bagel/https://galileospendulum.org/wp-content/uploads/2014/11/madhatter.jpgMad tea party"How is a raven like a writing-desk?" is not a question physics can answer, but the shape of a proton is. [Credit: John Tenniel]2014-11-07T19:21:25+00:00monthlyhttps://galileospendulum.org/2014/11/01/no-academic-science-hasnt-overcome-sexism/https://galileospendulum.org/wp-content/uploads/2014/11/me_and_alice.jpgteaching Alice in WonderlandHere I am teaching Alice in Wonderland about Möbius strips and other fun mathematical concepts at GeekGirlCon last month. According to cultural stereotypes promoted by the New York Times, I shouldn't bother because girls aren't interested in math. [Credit: GeekGirlCon on Flickr]2014-11-05T14:15:35+00:00monthlyhttps://galileospendulum.org/2014/11/02/lack-of-oxygen-may-have-delayed-the-evolution-of-complex-critters/https://galileospendulum.org/wp-content/uploads/2014/11/hallucigenia_large.gifHallucigenia, a Cambrian era oddityHallucigenia, an odd fossil from the Cambrian that is probably related to modern velvet worms. [Credit: Chip Clark, Smithsonian Institution]2014-11-02T20:20:57+00:00monthlyhttps://galileospendulum.org/2014/10/27/everything-you-wanted-to-know-about-inflation-but-were-afraid-to-ask/https://galileospendulum.org/wp-content/uploads/2014/10/southpole_observatory.jpgSouth Pole observatoryCosmology observatory at the South Pole, including the South Pole Telescope (SPT) on the left and BICEP2 on the right. [Credit: Stephen Hoover/University of Chicago]2014-10-27T18:12:55+00:00monthlyhttps://galileospendulum.org/2014/10/26/over-the-moon-with-china-and-luxembourg/https://galileospendulum.org/wp-content/uploads/2014/10/luxembourg_4m_probe.jpgLuxembourg 4M probeA model of the Manfred Memorial Moon Mission (4M), a communications experiment built by a privately-owned company in Luxembourg. [Credit: LuxSpace]2014-10-26T18:53:27+00:00monthlyhttps://galileospendulum.org/2014/10/22/when-genius-fails-us/https://galileospendulum.org/wp-content/uploads/2014/10/isaacnewton.jpgIsaac NewtonNoted alchemist and religious historian Isaac Newton.2014-10-23T05:09:32+00:00monthlyhttps://galileospendulum.org/2014/10/22/the-death-star-moon-has-a-weird-interior/https://galileospendulum.org/wp-content/uploads/2014/10/mimas_cassini.jpgSaturn's Death Star moon MimasSaturn's Death Star moon, Mimas, as seen by the Cassini orbiter. [Credit: Cassini Imaging Team, ISS, JPL, ESA, NASA; Digital Processing: Supportstorm]2014-10-22T12:43:56+00:00monthlyhttps://galileospendulum.org/2014/10/16/what-happened-in-the-first-instants-after-the-big-bang/https://galileospendulum.org/wp-content/uploads/2014/10/bicep.jpgBICEP2The BICEP2 telescope at the South Pole, designed to look for polarization of light that could be the sign of inflation. [Credit: Steffen Richter]2014-10-16T01:19:06+00:00monthlyhttps://galileospendulum.org/2014/10/14/ill-see-you-on-the-far-side-of-the-moon/https://galileospendulum.org/wp-content/uploads/2014/10/luna-3.giffar side of the Moon as seen by Luna 3The far side of the Moon as seen by the Luna 3 robotic probe in 1959. [Credit: NASA History Office]2014-10-17T06:58:44+00:00monthlyhttps://galileospendulum.org/2014/10/09/of-mobius-strips-and-klein-bottles/https://galileospendulum.org/wp-content/uploads/2014/10/klein_bottle_web.pngKlein_bottle_webRepresentation of a Klein bottle. As you can see the surface passes through itself, meaning it can't be made properly in the real world. [Credit: Tttrung for Wikipedia]https://galileospendulum.org/wp-content/uploads/2014/10/ggc_klein.pngGGC_kleinClick to get a template for a Klein bottle. Again, print out with as small margins as possible for best results.https://galileospendulum.org/wp-content/uploads/2014/10/ggc_mobius2.pngGGC_mobius2Click to get a printable template for five Mobius strips. Print this with as small margins as your printer will allow, and cut along the solid lines to get basic Mobius strip shapes.https://galileospendulum.org/wp-content/uploads/2014/10/mobius_twist.pngMobius twistDo the Mobius twist!2014-10-16T12:16:05+00:00monthlyhttps://galileospendulum.org/2014/10/05/the-gravity-of-antarctic-ice-loss/2014-10-06T07:55:24+00:00monthlyhttps://galileospendulum.org/2014/09/30/the-dark-matter-at-the-edge-of-the-map/2014-09-30T23:26:42+00:00monthlyhttps://galileospendulum.org/2014/09/29/to-mars-and-beyond/https://galileospendulum.org/wp-content/uploads/2014/09/mars_from_mangalyaan.jpgMars from MangalyaanMars, as seen by India's Mangalyaan orbiter. [Credit: Indian Space Research Organization]2014-09-29T18:38:28+00:00monthlyhttps://galileospendulum.org/2014/09/28/you-cant-get-rid-of-black-holes-that-easily/2014-10-02T07:44:25+00:00monthlyhttps://galileospendulum.org/2014/09/24/colliders-fit-for-gods/https://galileospendulum.org/wp-content/uploads/2014/09/grb_illustration.jpgcolliding neutron starsArtist's impression of two neutron stars colliding. [Credit: Dana Berry, SkyWorks Digital, Inc.]2014-10-09T03:59:06+00:00monthlyhttps://galileospendulum.org/2014/09/23/listen-to-me-on-the-bbc/https://galileospendulum.org/wp-content/uploads/2014/09/mars_orbiter_mission.jpgMars Orbiter MissionArtist's impression of the Mars Orbiter Mission, India's first probe to Mars. [Credit: Nesnad]2014-09-23T20:33:57+00:00monthlyhttps://galileospendulum.org/2014/09/22/why-i-am-still-unimpressed-with-the-space-station-dark-matter-search/https://galileospendulum.org/wp-content/uploads/2014/09/ams_power_spectrum.jpgresults from the first AMS-02 releaseThe results from the first AMS-02 release, last year. [Credit: AMS collaboration]https://galileospendulum.org/wp-content/uploads/2014/09/ams_plot2.pngAMS-02 resultsPlot of the latest AMS-02 results (red) compared with other experiments. [Credit: CERN]2014-09-22T15:55:11+00:00monthlyhttps://galileospendulum.org/2014/09/17/invasion-of-the-geekgirlcon/2014-09-17T19:59:45+00:00monthlyhttps://galileospendulum.org/2014/09/14/some-early-galaxies-were-oddly-heavy-and-starry/https://galileospendulum.org/wp-content/uploads/2014/09/splash_survey.jpgCOSMOS fieldGalaxies in infrared (red) and visible light (blue and green), in a survey showing that some early galaxies were much bigger babies than expected. [Credit: NASA/JPL-Caltech]2014-09-14T21:18:06+00:00monthlyhttps://galileospendulum.org/2014/09/07/the-milky-ways-place-in-the-spacious-heavens/https://galileospendulum.org/wp-content/uploads/2014/09/image_1_laniakea.jpgLaniakeaVisualization of the local Universe based on detailed observations of nearby galaxies. The red line encloses Laniakea, a proposed supercluster of galaxies containing the Milky Way, which is represented by the black dot at the image center. [Credit: SDvision interactive visualization software by Daniel Pomarède at CEA/Saclay, France]2014-09-07T18:19:05+00:00monthlyhttps://galileospendulum.org/2014/09/01/is-the-universe-a-hologram/https://galileospendulum.org/wp-content/uploads/2014/09/holometer.jpgholometerConstruction of the Holometer, an experiment to test a hypothesis about the structure of spacetime on the microscopic scale. [Credit: Fermilab]2014-09-01T15:13:57+00:00monthlyhttps://galileospendulum.org/2014/08/26/black-holes-into-darkness/https://galileospendulum.org/wp-content/uploads/2014/08/black-hole-event-atlas.pngsimulated black hole eventSimulation of a black hole creation event at the LHC. [ATLAS Experiment © 2014 CERN]2014-08-27T13:29:09+00:00monthlyhttps://galileospendulum.org/2014/08/25/the-song-of-the-black-hole/https://galileospendulum.org/wp-content/uploads/2014/08/m82_chandra_hst_spitzer.jpgInfrared and X-ray image of M82Composite infrared and X-ray image of M82, the "Cigar Galaxy". [Credit: NASA/JPL-Caltech/STScI/CXC/UofA/ESA/AURA/JHU]2014-08-25T18:34:16+00:00monthlyhttps://galileospendulum.org/2014/08/20/my-favorite-dark-matter-candidate/2014-08-20T14:54:58+00:00monthlyhttps://galileospendulum.org/2014/08/17/a-cloud-in-the-titanic-sky/https://galileospendulum.org/wp-content/uploads/2014/08/titanic_cloud_animation.gifanimation of clouds on TitanAnimation of clouds on Titan. [Credit: NASA/JPL-Caltech/Space Science Institute]https://galileospendulum.org/wp-content/uploads/2014/08/titanic_clouds.jpga cloud in the sky over TitanA cloud in the sky over Titan, possibly marking the beginning of the summer storms on Saturn's biggest moon. [Credit: NASA/JPL-Caltech/Space Science Institute]2014-08-17T20:59:18+00:00monthlyhttps://galileospendulum.org/2014/08/13/when-you-stare-into-the-bootes-void-does-the-bootes-void-also-stare-into-you/2014-08-13T21:09:56+00:00monthlyhttps://galileospendulum.org/2014/08/12/all-the-stars-are-blooming/2014-08-11T19:53:21+00:00monthlyhttps://galileospendulum.org/2014/08/11/the-first-spacecraft-to-orbit-a-comet-has-arrived/https://galileospendulum.org/wp-content/uploads/2014/08/comet_67p.pngComet 67PComet 67P/Churyumov–Gerasimenko, as seen by the Rosetta spacecraft. [Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA]2014-08-11T12:41:00+00:00monthlyhttps://galileospendulum.org/2014/08/05/helloooo-what-city-is-this-again-cleveland/https://galileospendulum.org/wp-content/uploads/2014/08/matthewfrancisshow.jpgThe Matthew Francis ShowThere is no such thing as The Matthew Francis Show, except in the imagination of Morgan Jackson, who created this image. However, I have never looked more like Isaac Asimov. [Credit: Morgan Jackson ]2014-08-05T17:38:25+00:00monthlyhttps://galileospendulum.org/2014/07/28/of-dark-matter-and-new-eyes-on-galaxy-structure/https://galileospendulum.org/wp-content/uploads/2014/07/massey2008_fig3_small.pngMapping the location of dark matterThis contour map shows the location of dark matter near galaxies, as determined using gravitational lensing. [Credit: Richard Massey/Nature]2014-07-28T10:58:17+00:00monthlyhttps://galileospendulum.org/2014/07/31/farewell-to-richmond/https://galileospendulum.org/wp-content/uploads/2014/07/big-ass_mug.jpgcoffee in a soup bowlOn occasion, the staff at Capital Coffee and Desserts would serve me coffee in a soup bowl. The day I took this photo, I obviously needed it, based on my bleary eyes and suboptimal hair.2014-07-28T10:14:56+00:00monthlyhttps://galileospendulum.org/2014/07/23/are-geniuses-like-einstein-superhuman/2014-07-23T14:12:01+00:00monthlyhttps://galileospendulum.org/2014/07/22/the-cosmos-laughs-at-our-puny-particle-colliders/https://galileospendulum.org/wp-content/uploads/2014/07/600px-tycho-supernova-xray.jpgTycho's supernova remnantTycho's supernova remnant puts our particle accelerators to shame. Bonus: two people I know helped create this X-ray image! [Credit: NASA/CXC/Rutgers/J.Warren & J.Hughes et al.]2014-07-21T23:11:39+00:00monthlyhttps://galileospendulum.org/2014/07/20/mapping-mars-at-night/https://galileospendulum.org/wp-content/uploads/2014/07/olympusmons_thermal.pngThermal map of Olympus MonsA thermal image of Olympus Mons (latitude 18.4, longitude -134), the largest volcano in the Solar System, as seen by the Mars Odyssey spacecraft. The black stripes are places where the data are incomplete. [Credit: Mars Space Flight Facility data/my selection]2014-07-20T16:17:34+00:00monthlyhttps://galileospendulum.org/2014/07/13/the-problem-of-richard-feynman/https://galileospendulum.org/wp-content/uploads/2014/07/smbc_feynman.gifpanel from Saturday Morning Breakfast CerealA panel from a Saturday Morning Breakfast Cereal comic about summoning the shade of Feynman, and its creepy consequences. Click to read the whole thing. [Credit: Zach Weinersmith]2014-07-16T13:16:43+00:00monthlyhttps://galileospendulum.org/2014/07/14/where-do-the-highest-energy-cosmic-rays-originate/https://galileospendulum.org/wp-content/uploads/2014/07/ta_detector.jpgTA DetectorOne of the 523 cosmic-ray detectors in the Telescope Array, located in the Utah desert. [Credit: John Matthews, University of Utah]2014-07-13T19:18:56+00:00monthlyhttps://galileospendulum.org/2014/07/09/mining-for-dark-matter-in-south-dakota/https://galileospendulum.org/wp-content/uploads/2014/07/winch_and_cable.jpgwinch and cableThe winch and cable mechanism controlling the "cages": the elevators that provide access to the lower levels of the Sanford Underground Research Facility in Lead, South Dakota. [Credit: moi]2014-07-09T00:06:14+00:00monthlyhttps://galileospendulum.org/2014/07/06/the-exoplanet-vanishes/https://galileospendulum.org/wp-content/uploads/2014/07/millennium_falcon_cockpit.jpgMillennium Falcon cockpit from Star Wars"Destroyed...by the Empire!"2014-07-07T14:15:45+00:00monthlyhttps://galileospendulum.org/2014/06/29/twinkle-twinkle-little-star-we-cant-see-you-where-you-are/https://galileospendulum.org/wp-content/uploads/2014/06/hidden_white_dwarf.pnghidden white dwarf"I see nothing." "What you do not see is a white dwarf with such low temperature that it's solidified."2014-06-29T17:24:10+00:00monthlyhttps://galileospendulum.org/2014/06/24/solutions-summit-representation-harassment-and-cookies/https://galileospendulum.org/wp-content/uploads/2014/06/cookie.jpgcookieI don't participate in activities like these to get a cookie, but I managed to acquire one anyway.2014-06-24T23:45:49+00:00monthlyhttps://galileospendulum.org/2012/05/30/i-like-roll-models-with-plum-jam/https://galileospendulum.org/wp-content/uploads/2012/05/yerkes_dome_snap.jpgYerkes ObservatoryThe 90-foot-diameter dome at Yerkes Observatory in Wisconsin. I visited Yerkes during my trip, simply because I've always wanted to see it: beneath that dome is the world's largest refracting (lens-based) telescope. While the 40-inch telescope was pretty much obsolete from the moment it was built (a 40-inch reflecting telescope is much better, cheaper, and easier to build and maintain), it's a monument to engineering ingenuity.2014-06-23T13:09:49+00:00monthlyhttps://galileospendulum.org/2014/06/22/the-disappearing-reappearing-black-hole/2014-06-22T15:45:15+00:00monthlyhttps://galileospendulum.org/2014/06/16/dating-the-moon-whats-60-million-years-between-friends/2014-06-16T20:13:20+00:00monthlyhttps://galileospendulum.org/2014/06/08/mega-earths-and-mini-neptunes-exoplanets-get-weirder/2014-06-08T20:36:51+00:00monthlyhttps://galileospendulum.org/2014/06/05/einstein-in-spaaaaace/https://galileospendulum.org/wp-content/uploads/2014/06/lorand_eotvos.jpgHungarian physicist Lorand EotvosThe great Hungarian physicist Loránd Eötvös (usually pronounced "utvush" in English) performed the first modern precision test of the equivalence principle. I didn't have space to talk about him in my Daily Beast article, but he deserves a mention. [Credit: Hungarian Academy of Sciences]2014-06-04T23:51:52+00:00monthlyhttps://galileospendulum.org/2013/10/03/portrait-of-a-black-hole-part-1/https://galileospendulum.org/wp-content/uploads/2013/10/eom1.pngEOMhttps://galileospendulum.org/wp-content/uploads/2013/10/eom2.pngEOM2https://galileospendulum.org/wp-content/uploads/2013/10/simplifications2.pngsimplifications2https://galileospendulum.org/wp-content/uploads/2013/10/eom.pngEOMhttps://galileospendulum.org/wp-content/uploads/2013/10/simplifications.pngsimplificationshttps://galileospendulum.org/wp-content/uploads/2013/10/schwarzschild_metric.pngSchwarzschild_metrichttps://galileospendulum.org/wp-content/uploads/2013/10/death_plunge2.pngDeath plunge, reduxEven though the object starts with the same orbital momentum, it's far enough away from the black hole that as the current carries it slowly in, it doesn't have enough oomph to escape again.https://galileospendulum.org/wp-content/uploads/2013/10/unstable_equilibrium.pngunstable equilibriumThe black dot on the phase portrait represents an unstable circular orbit. If an object starts near that orbit but not quite on it, it will fall into a very different orbital pattern.https://galileospendulum.org/wp-content/uploads/2013/10/precessing_ellipse.pngPrecessing elliptical orbitIf the orbital momentum is large enough, objects can orbit the black hole in stable patterns. Here we have an object that starts at the same position as above, but it has enough orbital momentum to make it fall into a nearly elliptical orbit. In the phase diagram, this takes the shape of a squashed loop around the green diamond; in the real orbital image, it forms a Spirograph pattern, a "precessing" ellipse that doesn't repeat itself on each orbit.https://galileospendulum.org/wp-content/uploads/2013/10/phase_portrait_key.pngGuide to phase portraitsGuide to phase portraits. If a black hole is non-rotating, it looks the same no matter what angle you view it, so we only need to worry about the distance from the black hole. That's the horizontal axis: the left edge is the black hole itself, while the farther you go right, the farther from the black hole you are. The vertical axis is a measure of how much the object is moving toward (upper half) or away from (lower half) the black hole.2014-06-03T22:17:40+00:00monthlyhttps://galileospendulum.org/2014/06/03/mary-mary-quite-contrary-how-does-your-black-hole-grow/https://galileospendulum.org/wp-content/uploads/2014/06/quasar_3c186.jpgquasar 3c186One of the most distant black holes we’ve yet observed: the quasar 3c186. [Credit: NASA/CXC/SAO/A.Siemiginowska et al. Optical: AURA/Gemini Obs.]2014-06-03T20:45:52+00:00monthlyhttps://galileospendulum.org/2014/06/01/for-once-i-aint-even-mad-the-tale-of-grbm31/https://galileospendulum.org/wp-content/uploads/2014/06/lmc_uv_swift.jpgLMC as seen by SwiftThe Large Magellanic Cloud (LMC), the largest satellite galaxy of the Milky Way, as seen by the Swift observatory in ultraviolet light. [Credit: NASA/Swift/S. Immler (Goddard) and M. Siegel (Penn State)]2014-06-01T18:50:10+00:00monthlyhttps://galileospendulum.org/2014/05/30/dont-say-quantum-when-you-mean-i-dont-understand/https://galileospendulum.org/wp-content/uploads/2014/05/physicist_life_cycle_panel.gifpanel from SMBCPanel from Saturday Morning Breakfast Cereal by Zach Weinersmith.2014-05-30T20:04:01+00:00monthlyhttps://galileospendulum.org/2014/05/27/a-nursery-for-baby-giant-galaxies/https://galileospendulum.org/wp-content/uploads/2014/05/jkcs041.jpgthe distant galaxy cluster JKCS 041A composite X-ray/optical image of the galaxy cluster JKCS 041, 9.9 billion light-years away. [Credit: Credits: X-ray: NASA/CXC/INAF/S.Andreon et al. Optical: DSS; ESO/VLT]2014-05-27T16:08:59+00:00monthlyhttps://galileospendulum.org/2014/05/22/a-photon-smashing-machine/2014-05-22T21:08:49+00:00monthlyhttps://galileospendulum.org/2014/05/18/the-weirdest-objects-in-the-universe/https://galileospendulum.org/wp-content/uploads/2014/05/dust_ring_around_magnetar.jpgring of dust around a magnetarThe ring of dust around a magnetar: a neutron star with an extraordinarily strong magnetic field. [Credit: NASA/JPL-Caltech/S. Wachter (Spitzer Science Center)]2014-05-18T20:04:14+00:00monthlyhttps://galileospendulum.org/2012/10/06/the-blog-from-the-pit-of-hell/https://galileospendulum.org/wp-content/uploads/2012/10/lucifer_crop.jpgLucifer from Dore's illustrations for Divine ComedyFrom a physical model of the Solar System to religious metaphor. [Credit: Gustav Dore, illustration from Dante's Divine Comedy]2014-05-14T16:19:42+00:00monthlyhttps://galileospendulum.org/2014/05/14/the-predictability-of-randomness-and-the-age-of-earth/https://galileospendulum.org/wp-content/uploads/2014/05/canyon-diablo-meteorite.jpgCanyon Diablo meteoriteThe Canyon Diablo meteorite, which was used to provide the first accurate measurement of Earth's age. [Credit: Geoffrey Notkin]https://galileospendulum.org/wp-content/uploads/2014/05/halflife2.pngHalf-life: smaller populationNuclear decay calculation for a smaller population of atoms, with the same half-life as before. Now we can see that if we fail to correct for background radiation, we run into some trouble. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/05/halflife1.pnghalf-life: large populationHalf-life calculation for a large population of atoms. The half-life is the point in the cross-hairs, which is about 13.5 in these time units. I included both the calculation with and without correcting for background radiation. In this case, the difference is small. [Credit: moi]2014-05-17T18:32:01+00:00monthlyhttps://galileospendulum.org/2014/05/12/all-hats-all-the-time/https://galileospendulum.org/wp-content/uploads/2014/05/frog_hat.jpgfrog hatYou all remember the band Frog Hat?2014-05-12T23:04:01+00:00monthlyhttps://galileospendulum.org/2014/05/12/how-a-black-hole-can-kick-stars-out-of-the-galaxy/https://galileospendulum.org/wp-content/uploads/2014/05/hypervelocity_star.jpghypervelocity starAn utterly ridiculous artist's impression of a hypervelocity star getting kicked out of the Milky Way. [Credit: Ben Bromley, University of Utah]2014-05-12T12:07:06+00:00monthlyhttps://galileospendulum.org/2014/05/05/black-holes-are-the-future/2014-05-06T23:23:14+00:00monthlyhttps://galileospendulum.org/2014/05/04/of-rebel-bases-and-habitable-exomoons/https://galileospendulum.org/wp-content/uploads/2014/05/chewie_shirt.jpgChewie is my co-pilotT-shirt by R. Stevens2014-05-04T19:15:15+00:00monthlyhttps://galileospendulum.org/2012/03/05/moonday-a-bite-sized-moon/https://galileospendulum.org/wp-content/uploads/2012/03/ida_dactyl_comparison.pngIda (and Dactyl) compared with EarthIda and Dactyl compared with Earth. Even showing only a small portion of Earth, Ida is tiny and Dactyl is invisible!https://galileospendulum.org/wp-content/uploads/2012/03/ida_dactyl.jpgasteroid Ida and its moon DactylThe asteroid Ida and its moon Dactyl. Ida is only 54 kilometers (about 34 miles) at its longest, while Dactyl is only 1.6 kilometers (1 mile) across. Sightings of the Little Prince standing on its surface are currently unconfirmed.2014-05-04T14:26:12+00:00monthlyhttps://galileospendulum.org/2011/09/15/a-planet-with-two-suns/https://galileospendulum.org/wp-content/uploads/2011/09/kepler-16b.pngKepler-16bThe planet Kepler-16b "Tatooine" in orbit around its binary host stars. The orbits are drawn more or less to show scale, but please don't take a ruler to them! The stars and planet sizes are decidedly not to scale.2014-05-04T14:24:29+00:00monthlyhttps://galileospendulum.org/2012/04/02/moonday-searching-for-endor/2014-05-04T14:24:10+00:00monthlyhttps://galileospendulum.org/2014/04/28/cosmic-carnage-two-black-holes-devouring-a-helpless-star/https://galileospendulum.org/wp-content/uploads/2014/04/binary_smbh.jpgbinary supermassive black holesArtist's impression of a pair of supermassive black holes in the act of dismembering a luckless star. [Credit: ESA/C. Carreau]2014-05-04T06:50:48+00:00monthlyhttps://galileospendulum.org/2014/04/25/how-a-trickster-galaxy-fooled-us-into-thinking-a-supernova-was-too-bright/https://galileospendulum.org/wp-content/uploads/2014/04/supernova_lens.pnga trickster galaxyThe gravitational field of the trickster galaxy in the inset magnified a supernova behind it, making it appear 30 times too bright. [Credit: Kavli IPMU / CFHT]2014-04-25T14:13:59+00:00monthlyhttps://galileospendulum.org/2014/04/21/the-quest-for-another-earth/https://galileospendulum.org/wp-content/uploads/2014/04/kepler186f_comparisongraphic.jpgnew exoplanet discovery Kepler-186fArtist's conception of the new exoplanet discovery Kepler-186f, compared with Earth. The orbits of planets in the Kepler-186 system are all much smaller than comparable ones in the Solar System because the host star itself is smaller. [Credit: NASA Ames/SETI Institute/JPL-Caltech]2014-04-22T07:57:53+00:00monthlyhttps://galileospendulum.org/2014/04/22/a-white-dwarf-magnifier/https://galileospendulum.org/wp-content/uploads/2014/04/white_dwarf_lensing.jpglensing of a star by a white dwarfDiagram of lensing of a star by a white dwarf in the same binary system. [Credit: Eric Agol]2014-04-21T22:15:15+00:00monthlyhttps://galileospendulum.org/2014/04/20/still-a-work-in-progress/https://galileospendulum.org/wp-content/uploads/2014/04/drill_baby_drill.jpgdown in the minePortrait of the writer with a very big drill. This was taken in the former Homestake gold mine, which now houses the Sanford Underground Research Facility, including the LUX dark matter detector. [Credit: moi]2014-04-20T17:33:47+00:00monthlyhttps://galileospendulum.org/2011/12/12/moonday-eclipse/https://galileospendulum.org/wp-content/uploads/2011/12/lunar_eclipse.jpglunar eclipseThe Moon during the total lunar eclipse. Note the deep orange-red color. [Credit: Doug Murray]https://galileospendulum.org/wp-content/uploads/2011/12/moon_phases.pngMoon phasesIf we view the Earth from a vantage point somewhat over the North Pole, we'll see a view like this cartoon. As the Moon orbits, half of it is always illuminated, but not the same half. The part that's illuminated is what we think of as the phase. The 8 pictures around the edge show different phases depending on where the Moon is relative to the day and night side of Earth. Thus, the full Moon is visible at night, a half-moon will be visible for part of both night and day, and a new Moon is when the whole near side is in shadow.2014-04-14T21:06:02+00:00monthlyhttps://galileospendulum.org/2014/04/11/every-devil-i-meet-becomes-a-friend-of-mine/https://galileospendulum.org/wp-content/uploads/2014/04/view1.jpgDevils Tower from the baseA view of Devils Tower from the base, showing both the columnar structure but also how imposing it is. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/04/close-up1.jpgDevils Tower close-upA close-up view of Devils Tower reveals that it is made of a bundle of hexagonal columns (with a few other shapes as well). [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/04/distant_view.jpgDevils Tower, WyomingDevils Tower, a volcanic formation in Wyoming, as seen from a distance across the valley. [Credit: moi]2014-04-12T19:51:56+00:00monthlyhttps://galileospendulum.org/2014/04/06/memento-mori/https://galileospendulum.org/wp-content/uploads/2014/04/helix_nebula.jpgThe Helix NebulaThe Helix Nebula is a particularly beautiful example of a planetary nebula: the outer layers shed by a dying star. The death of our Sun will eventually produce a planetary nebula, but only time will tell whether it will be as striking as the Helix Nebula. [Credit: NASA, ESA, C.R. O'Dell (Vanderbilt University), M. Meixner and P. McCullough (STScI)]2014-04-06T14:09:44+00:00monthlyhttps://galileospendulum.org/2014/04/02/relativeity/https://galileospendulum.org/wp-content/uploads/2014/04/my_family.jpgfamilyMy maternal grandparents (center) at their 50th wedding anniversary, surrounded by their children, with their spouses.2014-04-03T00:52:46+00:00monthlyhttps://galileospendulum.org/2014/03/31/seeing-the-most-distant-galaxies-in-the-universe/https://galileospendulum.org/wp-content/uploads/2014/03/macs1149_2223.jpga very distant galaxyThe inset image at bottom right is one of the most distant galaxies in the Universe. Gravity from the galaxy cluster in the largest image magnified the light from that galaxy via gravitational lensing, making it barely visible. [Credit: NASA, ESA, W. Zheng (JHU), M. Postman (STScI), and the CLASH Team]2014-03-31T15:27:10+00:00monthlyhttps://galileospendulum.org/2014/03/20/podcast-a-few-contrarian-thoughts-about-bicep2/https://galileospendulum.org/wp-content/uploads/2014/03/song-of-the-universe-small.jpgsong of the universeI didn't record this podcast in front of a backdrop of the cosmic microwave background, but if you think it's cooler, you can pretend I did. [Credit: Tony Hitchcock]2014-03-21T16:30:41+00:00monthlyhttps://galileospendulum.org/2014/03/17/a-quick-note-about-todays-big-cosmology-announcement/2014-03-17T19:07:04+00:00monthlyhttps://galileospendulum.org/2014/03/14/pi-day-the-i-and-the-pi/2014-03-14T14:52:15+00:00monthlyhttps://galileospendulum.org/2014/03/10/we-are-stardust-we-are-golden-we-are-billion-year-carbon/2014-03-31T19:36:56+00:00monthlyhttps://galileospendulum.org/2014/03/06/invisibility-and-community/2014-03-09T13:28:01+00:00monthlyhttps://galileospendulum.org/2014/03/08/madame-wu-and-the-backward-universe/https://galileospendulum.org/wp-content/uploads/2014/03/wu_experiment.pngWu's experimentCartoon of the Wu experiment: if parity was preserved, then the emission of electrons would change if you reversed the orientation of the experiment. Instead, she found that the electrons always shot out the same way relative to the cobalt atoms' spin, showing that the weak force violates the law of parity. [Credit: Matthew Francis]https://galileospendulum.org/wp-content/uploads/2014/03/reflections.pngparity transformations vs. mirror imagesParity transformations aren't quite the same as mirror images. The upper part of the diagram shows a mirror image, in which the direction of particle motion is left unchanged, while the spin is reversed. A parity transformation, however, leaves spin untouched while it flips the direction of motion. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/03/madame_wu_small.jpgChien-Shiung Wu The great experimental physicist Chien-Shiung Wu in 1958. [Credit: Smithsonian Institution]2014-03-08T16:48:24+00:00monthlyhttps://galileospendulum.org/2014/02/24/entangled-by-quantum-mechanics/2014-02-25T13:04:26+00:00monthlyhttps://galileospendulum.org/2014/02/23/how-should-we-report-incremental-science/https://galileospendulum.org/wp-content/uploads/2014/02/negative-data_panel.pngpanel from "Upturned Microscope"Click for the whole comic. [Credit: Nik Papageorgiou]2014-02-23T22:30:30+00:00monthlyhttps://galileospendulum.org/2014/02/14/a-scientific-valentine/2014-02-18T16:37:00+00:00monthlyhttps://galileospendulum.org/2014/02/13/pulling-back-the-curtain-of-science/2014-02-14T23:17:12+00:00monthlyhttps://galileospendulum.org/2014/02/09/nuance-complexity-and-creationism/2014-02-12T17:09:51+00:00monthlyhttps://galileospendulum.org/2014/01/30/playing-dice-with-the-universe-polarization-revisited/https://galileospendulum.org/wp-content/uploads/2014/01/thousand_photons.pngprobability, illustratedIf you increase the number of photons to ever-higher amounts, it becomes even more clear that half of them get through the filter. Here I've used 1000 photons, and you can see the area both above and below the curve are getting filled in. [Credit: moi]2014-01-30T21:18:54+00:00monthlyhttps://galileospendulum.org/2014/01/23/quantum-mechanics-a-polarizing-topic/https://galileospendulum.org/wp-content/uploads/2014/01/3d_glasses.jpgpolarized 3D glassesThese 3D glasses (from an exhibition on Egypt at the Virginia Museum of Fine Arts, which explains the motif) have polarizing filters in each eye. If you look closely, you can see that one eye is darker than the other; that's because the light from the computer monitor is polarized in such a way that it passes through one filter but not the other. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/01/three_filters.pngthree polarizing filtersAdding a third filter between the two in the previous diagram with orientation between the two allows some transmission of light. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/01/two_filters.pngtwo polarizing filtersIf you add a second polarizing filter with perpendicular orientation to the first, no photon can pass through both. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2014/01/simple_filter.pnga photon and a single polarizing filterSchematic of a photon from an unpolarized light source passing through a single polarizing filter. [Credit: moi]2014-01-30T18:04:49+00:00monthlyhttps://galileospendulum.org/2014/01/13/why-does-the-sun-shine/https://galileospendulum.org/wp-content/uploads/2014/01/sun_on_jan11.jpgThe Sun on January 11, 2014Ladies and gentlemen, the Sun! This ultraviolet image was taken on the morning of January 11, 2014 by the Solar and Helioseismographic Observatory (SoHO). [Credit: ESA/NASA]2014-01-13T17:09:56+00:00monthlyhttps://galileospendulum.org/2014/01/10/new-theories-are-hard-to-get-right-but-thats-ok/2014-02-07T03:37:58+00:00monthlyhttps://galileospendulum.org/2014/01/02/no-dark-matter-is-not-messing-up-gps-measurements/2014-01-08T14:17:18+00:00monthlyhttps://galileospendulum.org/2014/01/07/the-triumphant-return-of-cosmoacademy/https://galileospendulum.org/wp-content/uploads/2014/01/super-nova.jpgSuper-novaMy SUPERnova t-shirt shows how prepared I am for the 2014 season of online classes at CosmoAcademy. [T-shirt is from Threadless, photo is courtesy of moi]2014-01-06T20:04:45+00:00monthlyhttps://galileospendulum.org/2014/01/01/the-road-goes-ever-on-and-on/https://galileospendulum.org/wp-content/uploads/2014/01/road_to_mcdonald.jpgthe road to McDonald ObservatoryThe road leading to McDonald Observatory in western Texas. The dome on the left houses the Hobby-Eberly Telescope (HET), which I visited for my now-defunct book. [Credit: moi]2014-01-01T20:33:40+00:00monthlyhttps://galileospendulum.org/2013/12/24/a-sudden-star-science-christmas/https://galileospendulum.org/wp-content/uploads/2013/12/v838_mon.jpgevolution of star V838 MonocerotisThe evolution of the star V838 Monocerotis, which suddenly flared to 15,000 times the brightness of the Sun before fading. This series of images shows the outburst at various stages; it is still rapidly changing today. [Credit: NASA/ESA/The Hubble Heritage Team (STScI/AURA)]2013-12-25T16:08:23+00:00monthlyhttps://galileospendulum.org/2013/12/23/a-candle-and-a-giant-planet-science-advent-23/https://galileospendulum.org/wp-content/uploads/2013/12/jupiter_from_voyager_1.jpgJupiter's cloudsJupiter's clouds as seen by Voyager 1. While we often focus on the huge storms — the Great Red Spot at upper right — instead look at the turbulent whorls of clouds surrounding it. [Credit: NASA/Caltech/JPL]2013-12-23T17:39:05+00:00monthlyhttps://galileospendulum.org/2013/12/21/a-swiftly-tilting-planet-science-advent-21/2013-12-21T22:00:57+00:00monthlyhttps://galileospendulum.org/2013/12/20/the-breath-of-the-world-science-advent-20/https://galileospendulum.org/wp-content/uploads/2013/12/winds_waterman_projection.pngglobal wind patternsA visualization of global wind patterns on Earth, using the Waterman projection for the map. The colors represent different major patterns, and you can see the shapes of landmasses below. [Credit: Cameron Beccario]2013-12-20T18:21:28+00:00monthlyhttps://galileospendulum.org/2013/12/22/if-you-love-a-flower-found-on-a-star-science-advent-22/https://galileospendulum.org/wp-content/uploads/2013/12/vesta.jpgthe asteroid VestaThe asteroid Vesta, as seen by the Dawn space probe. Vesta is the second largest asteroid in the Solar System. [Credit: NASA, JPL-Caltech, UCLA, MPS, DLR, IDA]2013-12-20T14:56:52+00:00monthlyhttps://galileospendulum.org/2013/12/19/an-astronomical-selfie-science-advent-19/https://galileospendulum.org/wp-content/uploads/2013/12/veritas.jpgone of the four VERITAS telescopesOne of the four VERITAS telescopes seen from the side. [Credit: moi]2013-12-20T13:50:28+00:00monthlyhttps://galileospendulum.org/2013/12/18/a-dance-of-giant-black-holes-science-advent-18/https://galileospendulum.org/wp-content/uploads/2013/12/binary_black_holes.pngbinary black holesAn image of a pair of possible supermassive black holes in radio light. [Credit: Chao-Wei Tsai et al.]2013-12-20T13:50:08+00:00monthlyhttps://galileospendulum.org/2013/12/17/a-distant-twin-science-advent-17/2013-12-20T13:49:38+00:00monthlyhttps://galileospendulum.org/2013/12/16/earths-shield-from-alien-particle-invasion-science-advent-16/https://galileospendulum.org/wp-content/uploads/2013/12/aurora_borealis.jpgAurora borealis over AlaskaThe Aurora borealis — the Northern Lights — over Alaska. The green color is emission from oxygen atoms high in the atmosphere, when charged particles from the Sun strike them. [Credit: Well_Lucio on Flickr]2013-12-17T04:39:19+00:00monthlyhttps://galileospendulum.org/2013/12/12/death-of-a-comet-science-advent-12/https://galileospendulum.org/wp-content/uploads/2013/12/soho_ison_timelaps.jpegTimelapse images of the death of Comet ISONTimelapse images of the death of Comet ISON, from the Solar and Heliospheric Observatory (SOHO). The comet entered the image from the lower right (the long white streak), but once it rounded the Sun (the red disk at the center) it had disintegrated. You can see it fading as it moves to the upper right of the image. [Credit: ESA/NASA/SOHO/SDO/GSFC]2013-12-15T20:41:01+00:00monthlyhttps://galileospendulum.org/2013/12/15/rabbit-moon-science-advent-15/https://galileospendulum.org/wp-content/uploads/2013/12/yutu_rover2.gifdeployment of the Yutu rover on the MoonVideo footage of the deployment of the Yutu rover on the Moon. This is sped up for a nice short clip, but you can clearly see the six-wheeled rover with solar panels rolling out. [Credit: CNSA / CCTV / Emily Lakdawalla]2013-12-15T12:17:54+00:00monthlyhttps://galileospendulum.org/2013/12/14/an-exoplanet-orrery-science-advent-14/https://galileospendulum.org/wp-content/uploads/2013/12/princeton_orrery.jpgRittenhouse Orrery at Princeton UniversityThe Rittenhouse Orrery was constructed in 1771 and sits near the entrance of the astronomy building at Princeton University. [Credit: Princeton University]2013-12-14T10:55:35+00:00monthlyhttps://galileospendulum.org/2013/12/13/a-hip-hop-cosmology-science-advent-13/2013-12-13T12:47:26+00:00monthlyhttps://galileospendulum.org/2013/12/11/a-dance-of-planets-and-probes-science-advent-11/https://galileospendulum.org/wp-content/uploads/2013/12/juno_trajectory.jpgJuno mission trajectoryThe trajectory of the Juno space probe through the Solar System. To gain the correct speed and direction, the probe followed a looping path, passing by Earth again this fall. [Credit: NASA/JPL]2013-12-12T14:08:19+00:00monthlyhttps://galileospendulum.org/2013/12/10/a-modern-stonehenge-science-advent-10/2013-12-10T20:45:29+00:00monthlyhttps://galileospendulum.org/2013/12/09/our-backyard-black-hole-science-advent-9/https://galileospendulum.org/wp-content/uploads/2013/12/sgr_astar_composite.jpgthe Milky Way's black hole, Sagittarius A*The Milky Way's black hole, known as Sagittarius A*, in radio (blue) and X-ray (magenta) light. The radio data shows a strong hint of a jet emanating from the black hole. [Credit: X-ray: NASA/CXC/UCLA/Z.Li et al; Radio: NRAO/VLA]2013-12-09T19:57:00+00:00monthlyhttps://galileospendulum.org/2013/12/08/a-perfect-hexagonal-storm-science-advent-8/https://galileospendulum.org/wp-content/uploads/2013/12/saturn_hexagon_experiment.jpgExperimental realization of a hexagonal vortexAn experimental realization of a hexagonal vortex. Click for a full description. [Credit: Ana Aguiar]https://galileospendulum.org/wp-content/uploads/2013/12/saturn_hexagon.gifthe hexagonal storm at Saturn's north poleAnimation of the hexagonal storm at Saturn's north pole, showing how it changes over time. This movie clip is assembled from about 10 hours of images from the Cassini spacecraft, with color added to highlight the features. [Credit: NASA/JPL-Caltech/SSI/Hampton University]2013-12-08T17:16:36+00:00monthlyhttps://galileospendulum.org/2013/12/07/a-new-star-in-the-southern-sky-science-advent-7/https://galileospendulum.org/wp-content/uploads/2013/12/nova_centauri_2013.jpgNova Centauri 2013It may look like a star, but Nova Centauri 2013 (visible briefly in the Southern Hemisphere) is actually a bright burst of light from the surface of a white dwarf. [Credit: Yuri Beletsky (Las Campanas Observatory, Carnegie Institution)]2013-12-07T14:25:17+00:00monthlyhttps://galileospendulum.org/2013/12/06/28-neutrinos-from-deep-space-science-advent-6/https://galileospendulum.org/wp-content/uploads/2013/12/icecube_event3.pngthird neutrino from deep space in IceCubeThe third detected neutrino from a source in deep space, as visualized by how it triggered detectors in the IceCube experiment. [Credit: IceCube Collaboration]2013-12-11T00:57:07+00:00monthlyhttps://galileospendulum.org/2013/12/05/gravity-a-love-story-science-advent-5/2013-12-05T16:30:41+00:00monthlyhttps://galileospendulum.org/2013/12/04/seeing-the-chemical-ties-that-bind-science-advent-4/https://galileospendulum.org/wp-content/uploads/2013/12/hydrogen_bonds.jpghydrogen bonds imaged by atomic force microscopeHydrogen bonds as imaged by an atomic force microscope. [Credit: Science]2013-12-04T21:23:06+00:00monthlyhttps://galileospendulum.org/2013/12/03/a-galaxy-of-exoplanets-science-advent-3/https://galileospendulum.org/wp-content/uploads/2013/12/xkcd_exoplanet_neighborhood.pngIt's a beautiful day in the neighborhood!"It's a beautiful day in the neighborhood!" Randall Munroe of xkcd visualized all the exoplanets in our galactic neighborhood, using statistical estimates based on observations. [Credit: Randall Munroe]2013-12-03T19:33:55+00:00monthlyhttps://galileospendulum.org/2013/12/02/the-twelve-fold-way-science-advent-2/https://galileospendulum.org/wp-content/uploads/2013/12/12fold_quasicrystal.jpg12-fold quasicrystalA 12-fold quasicrystal: a two-dimensional arrangement of atoms that can never fully repeat itself. The arrangement can be duplicated using three types of tiles, shaped like squares, flattened rhomboids (figures with four equal sides), and equilateral triangles. [Credit: Wolf Widdra]2013-12-02T00:33:06+00:00monthlyhttps://galileospendulum.org/2013/12/01/earths-cry-heavens-smile-science-advent-1/https://galileospendulum.org/wp-content/uploads/2013/12/earth.pngEarthThat dot is Earth. You're somewhere in that dot. [Credit: NASA/JPL-Caltech/SSI ]https://galileospendulum.org/wp-content/uploads/2013/12/enceladus.pngEnceladusThe highest resolution image linked above contains Saturn's moon Enceladus, which is barely more than a dot...yet you can see the cryovolcanoes that produced Saturn's E ring if you look closely. [Credit: NASA/JPL-Caltech/SSI]https://galileospendulum.org/wp-content/uploads/2013/12/day_earth_smiled_small.pngThe Day Earth SmiledThe Day Earth Smiled: a mosaic of images from the Cassini probe when it passed beyond Saturn so that the planet eclipsed the Sun. [Credit: NASA/JPL-Caltech/SSI]2013-12-01T16:22:18+00:00monthlyhttps://galileospendulum.org/2013/11/24/a-brief-reflection-on-the-absurd-success-of-science/https://galileospendulum.org/wp-content/uploads/2013/11/escher_illusion.jpg"Print Gallery" by M.C. Escher"Print Gallery" by M.C. Escher blends optical illusions together, but there's a place where the images can't fit together consistently: the very center, where Escher cheated by putting his signature.2013-11-25T02:47:36+00:00monthlyhttps://galileospendulum.org/2013/11/19/why-is-the-universe-expanding-if-gravity-is-attractive/https://galileospendulum.org/wp-content/uploads/2013/11/dark_energy.pngdark energy vs. matterMatter, whether ordinary or dark, is conserved: increasing the container size decreases the density of energy, and therefore the potential for further expansion. Dark energy on the other hand has constant density (in the simplest model), so the larger the box, the more dark energy there is, and the more potential for expansion.2013-11-19T20:36:07+00:00monthlyhttps://galileospendulum.org/2013/11/15/dont-fear-the-math/https://galileospendulum.org/wp-content/uploads/2013/11/gardiner_final.jpgsolutionThe solution to Martin Gardiner's puzzle, for those who don't mind spoilers.https://galileospendulum.org/wp-content/uploads/2013/11/gardiner_comic.png"how to" guidePhotocomic that hopefully will help guide you into making an interesting result.https://galileospendulum.org/wp-content/uploads/2013/11/klein_bottle2.pngKlein bottle templateTemplate for something that might end up looking a little surprising to you. Cut along the solid lines first, make the short arms into an untwisted loop, and the longer arms into a Mobius band. Then cut along the dashed lines (see the comic below for more help).https://galileospendulum.org/wp-content/uploads/2013/11/mobius_template.pngMobius strip templatePrinting instructions: this is sized to fill a US Letter-sized piece of paper. Set the margins as large as your printer can handle, and make sure they're equal on all edges (e.g. 0.5 cm on top, bottom, left, and right sides). Cutting along the solid lines gives you three starting points for Mobius strips. Once you've taped the ends, cut along the dashed lines.https://galileospendulum.org/wp-content/uploads/2013/11/harriet_small.jpgHarrietToday's post was tough to write, so here's my cat Harriet when she was a tiny kitten.2013-11-17T15:58:21+00:00monthlyhttps://galileospendulum.org/2011/11/22/topology-with-paper-and-scissors/https://galileospendulum.org/wp-content/uploads/2011/11/klein_filmstrip.jpgMaking a fake Klein bottleTo make a fake Klein bottle, cut a piece of paper into a cross shape, with one leg signficantly longer. Use that long leg to make a Mobius strip, then use the remaining two legs to make a cylinder around the Mobius strip. A "real" Klein bottle doesn't have edges like this, so the Mobius strip part would pass through the surface of the bottle at some point - it's mathematically just fine to do that, but not really possible to make using paper!https://galileospendulum.org/wp-content/uploads/2011/11/torus_filmstrip.jpgattempt to make a torusMy first attempt to make a torus wasn't 100% successful, but you're probably able to figure out an improvement on my design. I started by cutting squares out of a strip of paper, then making a cylinder. The final step connect the ends of the cylinder together, which in my case wasn't very donut-like (alas).https://galileospendulum.org/wp-content/uploads/2011/11/photo-44.jpgtwo types of Mobius stripThe left- and right-handed versions of the Mobius strip, showing chirality.https://galileospendulum.org/wp-content/uploads/2011/11/mobius_filmstrip.jpgMaking a Mobius stripMaking a Mobius strip in the version where the right edge is turned toward you.2013-11-15T15:59:58+00:00monthlyhttps://galileospendulum.org/2011/12/29/simply-connect-further-adventures-in-topology/https://galileospendulum.org/wp-content/uploads/2011/12/moebius.jpgA Mobius strip, whole, and cut along the circumference.Cutting a Mobius strip along the circumference doesn't create two strips.https://galileospendulum.org/wp-content/uploads/2011/12/torus.jpgtorusA torus is also not simply connected, but it has two kinds of Jordan lines that intersect at a single point.https://galileospendulum.org/wp-content/uploads/2011/12/cylinder.jpgcylinderA cylinder isn't simply connected, since the line running around the entire circumference can't be shrunk into a single point.https://galileospendulum.org/wp-content/uploads/2011/12/two_circles.jpgtwo circles meeting at a single pointTwo circles can meet at a single point, but they can't intersect at less than two places.https://galileospendulum.org/wp-content/uploads/2011/12/hole.jpgPaper with a holePutting a hole in a piece of paper creates two types of curves that aren't equivalent to each other: you can't deform the curve at the top into the curve surrounding the hole without cutting and rejoining. As a result, this paper is not a simply connected surface.2013-11-15T15:59:44+00:00monthlyhttps://galileospendulum.org/2012/01/12/the-hunt-for-the-wumpus-goes-on-in-my-apartment/https://galileospendulum.org/wp-content/uploads/2012/01/all_to_all.pngAll-to-all coupling in a network with 5 nodesAll-to-all coupling in a network with 5 nodes. The overlap in the links isn't another connection, since there isn't a blue dot (node) there.https://galileospendulum.org/wp-content/uploads/2012/01/kevin_bacon.pngMy two degrees of Kevin BaconMy friend went to elementary school with Kevin Bacon, so I have two degrees of Kevin Bacon. Note that I am connected to my friend through several links (mutual friends), but we each have friends not shared by the other.https://galileospendulum.org/wp-content/uploads/2012/01/wumpus.pngThe cave system in "Hunt the Wumpus"The cave system in "Hunt the Wumpus". Gregory Yob, the programmer of the original version, described the network as a "squashed dodecahedron". Each node is a room in the cavern, and is connected to exactly three other nodes.https://galileospendulum.org/wp-content/uploads/2012/01/abstract_network.pngA somewhat more abstract floor planA somewhat more abstract version of the picture above. The spatial relationships between the different rooms (nodes) are close to how they are on the floor plan, but the routes are drawn to connect them more directly, since the walls are gone.https://galileospendulum.org/wp-content/uploads/2012/01/house_network.pngMy apartment as a networkDifferent routes between rooms in an apartment based more or less on mine.2013-11-15T15:59:27+00:00monthlyhttps://galileospendulum.org/2012/06/28/inverse-square-law-a-tale-of-luminosity-gravity-and-topology/https://galileospendulum.org/wp-content/uploads/2012/06/newtons_law.pngnewtons_lawhttps://galileospendulum.org/wp-content/uploads/2012/06/inverse_square_equation.pnginverse_square_equationhttps://galileospendulum.org/wp-content/uploads/2012/06/box_size.pngcubical box for inverse square lawSince the shape of the box is irrelevant, it frees us to pick a simple one, such as this cube. The distance from the star at the cube's center to the edge of the cube is r.https://galileospendulum.org/wp-content/uploads/2012/06/inverse_square.pngtopology leads to the inverse square lawHow flux depends on distance: photons travel outward from the star. Since the total number of photons is constant, they must disperse as they travel outward, meaning the same number of photons are distributed over a larger area. The two images show that distribution increases with the square of distance, so to keep the photon count constant, the intensity of the light must drop with the inverse square of distance.https://galileospendulum.org/wp-content/uploads/2012/06/gauss_box.pngbox, with and without a starIf the box doesn't contain a star, the light detectors don't trigger (left), but if it does, the light detectors will show the presence of the star. This is true however big or small the box is, or even the box's shape.2013-11-15T15:59:11+00:00monthlyhttps://galileospendulum.org/2011/11/21/of-mobius-strips-and-the-shape-of-things/https://galileospendulum.org/wp-content/uploads/2011/11/klein.pngHomework 3Tape the left and right sides together, and though you won't be able to actually finish the shape, ponder what it would look like if you could also tape the top and bottom together like a Mobius strip.https://galileospendulum.org/wp-content/uploads/2011/11/torus.pnghomework 2Construct the shape shown by taping together the left and right edges, and (separately) the top and bottom edges. Hint: instead of starting with a square, try a long strip of paper instead, which will make your life easier.https://galileospendulum.org/wp-content/uploads/2011/11/sphere.pngsphereTo make a sphere, you need to squish together the entire top edge (colored blue) into a single point, and the bottom edge (colored cyan) into a single point, to make the North and South poles, respectively. If you can do that with ordinary paper, please send me a picture.https://galileospendulum.org/wp-content/uploads/2011/11/moebius2.pngMobius strip 2The other orientation of a Mobius strip. Now flip the right side 180 degrees away from you before taping.https://galileospendulum.org/wp-content/uploads/2011/11/moebius1.pngMoebius stripOne orientation of a Mobius strip. Connect the right and left edges, but turn the right side 180 degrees toward you before taping.https://galileospendulum.org/wp-content/uploads/2011/11/cylinder1.pngcylinderConnect the edges marked with red semicircles, but leave the other edges alone, and you get a cylinder. In the y-direction, you can travel forever (in the mathematical generalization) without ever reach an edge, while in the x-direction you'll eventually come back to your starting point.https://galileospendulum.org/wp-content/uploads/2011/11/flat.pngA boring piece of paper, without any folds, tears, or holes.A boring piece of paper, without any folds, tears, or holes. Any circle or other closed loop you draw will be equivalent to any other, topologically speaking.https://galileospendulum.org/wp-content/uploads/2011/11/latitude-longitude.gifLatitude and longitude linesLatitude lines (defining the East-West or "x" direction) are always parallel to each other; longitude lines define the North-South or "y" direction, but are only parallel at the Equator. At the North and South Poles, the East-West axis vanishes: if you are at the North Pole, the only direction you can travel is South. This is a coordinate singularity in mathematical terms. (Image from http://drifters.doe.gov/track-a-yoto/track-a-drifter.html)https://galileospendulum.org/wp-content/uploads/2011/11/mobius.jpgAugust Ferdinand MobiusAugust Ferdinand Mobius: mathematician and astronomer.2013-11-15T15:58:54+00:00monthlyhttps://galileospendulum.org/2013/11/08/i-dont-believe-in-science/https://galileospendulum.org/wp-content/uploads/2013/08/i_believe_in_science.jpgI believe in science[Credit: moi/WearScience.com]2013-12-05T23:03:41+00:00monthlyhttps://galileospendulum.org/2013/11/05/the-census-of-alien-worlds/2013-11-05T19:48:51+00:00monthlyhttps://galileospendulum.org/2013/11/03/so-close-yet-so-far/https://galileospendulum.org/wp-content/uploads/2013/11/proxima_centauri.pngProxima CentauriProxima Centauri, the closest star to the Solar System, as viewed by the Hubble Space Telescope. [Credit: ESA/Hubble & NASA]2013-11-05T04:01:19+00:00monthlyhttps://galileospendulum.org/2013/10/31/ghosts-in-the-detector-why-null-results-are-part-of-science-too/https://galileospendulum.org/wp-content/uploads/2013/10/lux.jpgthe LUX detectorThe Large Underground Xenon (LUX) detector. [Credit: Lawrence Berkley National Laboratory]https://galileospendulum.org/wp-content/uploads/2013/10/lux_results.pngplot of LUX resultsThe relative strengths of the photon and electron signals in the LUX detector. For low-mass WIMPs, the ratio represented by the vertical axis would be reduced into the region bounded by red lines. [Credit: LUX collaboration]2013-11-01T01:26:27+00:00monthlyhttps://galileospendulum.org/2013/08/06/the-mighty-neutrino-vs-a-cosmological-conundrum/https://galileospendulum.org/wp-content/uploads/2013/08/universe_content_cmb.jpgthe contents of the Universe 380,000 years after the Big BangThe contents of the Universe 380,000 years after the Big Bang. Note that neutrinos comprise about 10 percent of the total energy content of the cosmos at that time. [Credit: NASA / WMAP Science Team]2013-10-31T12:41:01+00:00monthlyhttps://galileospendulum.org/2013/03/17/irish-mathematics-for-st-patricks-day/https://galileospendulum.org/wp-content/uploads/2013/03/quaternions.pngquaternionshttps://galileospendulum.org/wp-content/uploads/2013/03/quaternion_plaque.jpgquaternion plaque on Brougham Bridge in Dublin, IrelandThe plaque on Brougham Bridge in Dublin, Ireland commemorating the discovery of quaternions by William Rowan Hamilton. [Credit: Geograph.org.uk ]2013-10-28T21:12:39+00:00monthlyhttps://galileospendulum.org/2013/10/28/drownyourtown-drown-the-world/https://galileospendulum.org/wp-content/uploads/2013/10/period3.pngperiod3https://galileospendulum.org/wp-content/uploads/2013/10/period2.pngperiod2https://galileospendulum.org/wp-content/uploads/2013/10/period1.pngperiod1https://galileospendulum.org/wp-content/uploads/2013/10/angular_momentum.pngangular_momentumhttps://galileospendulum.org/wp-content/uploads/2013/10/water_calc3.pngwater_calc3https://galileospendulum.org/wp-content/uploads/2013/10/water_calc2.pngwater_calc2https://galileospendulum.org/wp-content/uploads/2013/10/water_calc1.pngwater_calc1https://galileospendulum.org/wp-content/uploads/2013/10/sphere_volume.pngsphere_volumehttps://galileospendulum.org/wp-content/uploads/2013/10/waterworld.pngestimate of volume of extra water to make WaterworldAn estimate of volume of extra water to make Waterworld. I took the volume of an entire Earth made of water plus the extra bit for flooding to a depth of 8,800 meters, then subtracted the volume of Earth, leaving a spherical shell. (The thickness of the shell is exaggerated for clarity.)https://galileospendulum.org/wp-content/uploads/2013/10/flood_45m.jpgthe "flooding" of Richmond, VirginiaThe "flooding" of Richmond, Virginia: using a naive model of ocean-level rise, 45 meters of flooding would wipe out many of the lower lying areas in the city where I live.2013-10-28T13:28:42+00:00monthlyhttps://galileospendulum.org/2013/10/26/a-comment-on-comments-with-cats/2013-10-26T20:58:09+00:00monthlyhttps://galileospendulum.org/2013/10/25/what-do-we-call-a-theory-that-is-no-longer-viable/2013-10-25T23:33:21+00:00monthlyhttps://galileospendulum.org/2013/10/24/for-the-love-of-gauss-please-stop/https://galileospendulum.org/wp-content/uploads/2013/10/old_man_yells_at_cloud.jpgstill from "The Simpsons"Yes, I'm grumpy. [Credit: Fox]2013-10-24T15:46:46+00:00monthlyhttps://galileospendulum.org/2013/10/21/the-river-of-spacetime/https://galileospendulum.org/wp-content/uploads/2013/10/schwarzschild_current.png"currents" near a non-rotating black holeThe spacetime "currents" near a non-rotating black hole, where the length of the arrow indicates how strong the flow is.https://galileospendulum.org/wp-content/uploads/2013/10/the-wind-in-the-willows.jpgThe Wind in the WillowsMole and Ratty from "The Wind in the Willows". [Credit: E. H. Shepherd]2013-10-23T09:14:33+00:00monthlyhttps://galileospendulum.org/2013/10/14/black-hole-hair-and-the-dark-energy-problem/https://galileospendulum.org/wp-content/uploads/2013/10/laws_of_gravity_get_fuzzy_panel.pngpanel from "Get Fuzzy"[Credit: Darby Conley]2013-10-14T20:10:39+00:00monthlyhttps://galileospendulum.org/2013/10/08/the-2013-nobel-prize-in-physics-the-higgs-boson/https://galileospendulum.org/wp-content/uploads/2013/10/major_award.jpga major awardThe Nobel Prize is also a major award.https://galileospendulum.org/wp-content/uploads/2013/10/nobel_grumpycat.jpgNobel Prize GrumpycatGrumpy Cat shares my sentiments.2013-10-09T02:19:45+00:00monthlyhttps://galileospendulum.org/2012/07/06/everything-you-wanted-to-know-about-the-higgs-boson-but-were-afraid-to-ask/2013-10-08T15:18:57+00:00monthlyhttps://galileospendulum.org/2013/10/07/a-scientific-love-affair/https://galileospendulum.org/wp-content/uploads/2013/10/agn_model.pngunified model of AGNThe unified model of active galactic nuclei (AGN), slightly simplified. Whether we see a quasar, huge radio-emitting jets, or something else depends largely on the angle at which we view the galaxy. The accretion disk can be a strong X-ray emitter, but if we're looking down the jet, we might see only that light. [Credit: moi]2013-10-08T00:33:20+00:00monthlyhttps://galileospendulum.org/2013/10/02/of-fire-and-ice-and-harlow-shapley/https://galileospendulum.org/wp-content/uploads/2013/10/galactic_center.jpgthe center of the Milky WayThe center of the Milky Way lies at the upper left of this image from the 2MASS survey of galaxies. [Credit: 2MASS/G. Kopan, R. Hurt]2013-10-05T16:18:29+00:00monthlyhttps://galileospendulum.org/2013/09/23/all-black-holes-great-and-small/2013-09-25T07:39:27+00:00monthlyhttps://galileospendulum.org/2013/09/24/scientific-grumpfiness-and-open-mindedness/https://galileospendulum.org/wp-content/uploads/2013/09/cookie_monster.gifCookie MonsterCookie Monster with a Newton's cradle, because how do you illustrate a blog post like this?2013-09-24T20:15:03+00:00monthlyhttps://galileospendulum.org/2013/09/19/measuring-the-rotation-of-earth/https://galileospendulum.org/wp-content/uploads/2013/09/foucault_pantheon_small.jpgFoucault pendulumThe Foucault pendulum at the Pantheon in Paris, France. [Credit: Allie Wilkinson]2013-09-19T23:05:19+00:00monthlyhttps://galileospendulum.org/2013/09/17/the-big-bang-model-is-successful-for-a-reason/2013-09-18T20:34:56+00:00monthlyhttps://galileospendulum.org/2013/09/16/three-years-of-black-holes-and-yo-momma-jokes/https://galileospendulum.org/wp-content/uploads/2013/09/solar_system_yo_momma.jpgSolar system scaleThe current consensus is that the Oort Cloud is comprised of donut crumbs dropped by yo momma. [Credit: NASA/JPL-Caltech]2013-09-16T20:53:32+00:00monthlyhttps://galileospendulum.org/2013/09/13/mapping-the-dark-matter-in-the-tiniest-galaxies/https://galileospendulum.org/wp-content/uploads/2013/09/dm_density_dsph.pngDM_density_dSphhttps://galileospendulum.org/wp-content/uploads/2013/09/fornax_dsph.jpgthe Fornax dwarf spheroidal galaxyThe Fornax dwarf spheroidal galaxy, a satellite of the Milky Way. The brightness of this galaxy is sufficiently low that it's very hard to see, much less study. [Credit: ESO/Digital Sky Survey 2]2013-09-13T18:06:51+00:00monthlyhttps://galileospendulum.org/2013/09/11/status-of-the-book-in-progress/2013-09-11T20:09:27+00:00monthlyhttps://galileospendulum.org/2013/09/10/do-it-yourself-science-at-geekgirlcon/https://galileospendulum.org/wp-content/uploads/2013/09/emily_is_me_panel.pngpanel from Questionable ContentHelp send me to GeekGirlCon so I can talk about science in a more productive way. [Credit: Jeph Jacques; click for the whole comic]2013-09-10T18:06:37+00:00monthlyhttps://galileospendulum.org/2013/09/06/how-to-watch-the-ladee-launch-tonight/https://galileospendulum.org/wp-content/uploads/2013/09/minotaur_v_on_pad.jpgMinotaur V rocketThe Minotaur V rocket on the launchpad at NASA Wallops Flight Facility. The rocket is carrying the Lunar Atmosphere and Dust Environment Explorer (LADEE) probe, bound for the Moon. [Credit: moi]2013-09-06T21:26:52+00:00monthlyhttps://galileospendulum.org/2013/09/05/of-maps-and-math-and-buckminster-fuller/https://galileospendulum.org/wp-content/uploads/2013/09/dymaxmap2.jpgDymaxion mapOne version of the Dymaxion map, which broke away from the strict icosahedral structure, while keeping the basic idea. [Credit: Buckminster Fuller Institute]https://galileospendulum.org/wp-content/uploads/2013/09/embedded_icosahedron.pngprinciple behind Dymaxion mapThe principle behind Dymaxion map: embed an icosahedron (20-sided solid shape) in a sphere, where the average radius is the same for both. Some of the sphere will project beyond the sides of the icosahedron, while the corners of the icosahedron stick out beyond the sphere. However, this distorts the world less because it's projecting onto 20 surfaces instead of one.https://galileospendulum.org/wp-content/uploads/2013/09/stereographic.pngstereographic projectionThe stereographic projection (in one version at least) is obtained by placing Earth on a flat plane. See the text following for its description.https://galileospendulum.org/wp-content/uploads/2013/09/upside_down_map.jpg"upside down" world mapAn "upside-down" world map, placing south at the top. Australians and southern Africans no doubt are asking "what's wrong with this?"2013-09-05T00:36:49+00:00monthlyhttps://galileospendulum.org/2012/04/16/moonday-this-one-is-for-the-oatmeal/https://galileospendulum.org/wp-content/uploads/2012/04/moon_sun_scale.pngSun and Moon to scaleEarth and the Moon are simply too small compared to the Sun to draw everything exactly to scale. The size of Earth, Moon, Sun, and 1 Moon unit are to scale, but the distance between Earth and the Sun is too big to include! Note that the Sun itself is significantly larger than 1 Moon unit. (Click for a much larger version!)https://galileospendulum.org/wp-content/uploads/2012/04/moon_sun_sizes.pnga toy solar systemA toy Solar System in which the Sun is only 3 times the diameter of the Moon. For the Sun and Moon to appear the same size in the sky, the Sun only needs to be three times as far away.https://galileospendulum.org/wp-content/uploads/2012/04/oatmeal_panel.pngpanel from "The Oatmeal"Advice for bloggers from The Oatmeal.2013-09-02T18:43:49+00:00monthlyhttps://galileospendulum.org/2013/08/30/atmospheric-science-in-a-bolt-of-lightning/2013-08-30T15:47:26+00:00monthlyhttps://galileospendulum.org/2013/08/29/naming-the-animals-in-the-particle-zoo/https://galileospendulum.org/wp-content/uploads/2013/08/cdf_detector.jpgCDF detectorThe original core of the Collider Detector at Fermilab (CDF), which is bristling with silicon chips and other means of detecting and identifying particles. CDF and DZero are the two big detectors at the Tevatron. [Credit: moi]2013-08-31T13:52:18+00:00monthlyhttps://galileospendulum.org/2013/08/28/microcosmos/https://galileospendulum.org/wp-content/uploads/2013/08/dzero_wall_small.jpghigh bay at DZeroThe high bay of the DZero detector at Fermilab. The detector itself lies behind the concrete wall covered in the flags of the 18 nations participating in the project. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2013/08/dzerologo.jpgDZero logoThe DZero logo, drawn by the great cartoonist George Booth.2013-08-28T15:29:09+00:00monthlyhttps://galileospendulum.org/2013/08/22/destruction-and-beauty-in-a-distant-galaxy/https://galileospendulum.org/wp-content/uploads/2013/08/m87_movie.gifM87 jet animation in radio lightFluctuations in the jet from M87 in radio light, as seen using the Very Long Baseline Array (VLBA). [Credit: NRAO]2013-08-22T19:24:08+00:00monthlyhttps://galileospendulum.org/2012/09/27/big-telescopes-reveal-the-maelstrom-around-a-black-hole/https://galileospendulum.org/wp-content/uploads/2012/09/doeleman3hr.jpgsimulations of gas circling a black holeNumerical simulations of gas circling a rotating black hole, showing the birth of a jet like that seen in M87. [Credit: Avery E. Broderick (University of Waterloo/Perimeter Institute)]https://galileospendulum.org/wp-content/uploads/2012/09/rotating_black_hole.pngDiagram of a rotating black holeDiagram of a rotating black hole, from "top" and "side" views. The ergosphere is what's important for this post: the region of space surrounding the black hole where nothing can remain at rest, thanks to the flow of spacetime. Even beyond the ergosphere, spacetime is shaped such that particles will tend to rotate along with the black hole, a phenomenon known as frame dragging.2013-08-22T18:45:45+00:00monthlyhttps://galileospendulum.org/2013/08/19/the-weird-and-wonderful-world-of-quasiparticles/2013-08-19T20:33:48+00:00monthlyhttps://galileospendulum.org/2013/08/18/how-i-learned-to-stop-worrying-and-tolerate-the-multiverse/https://galileospendulum.org/wp-content/uploads/2013/08/evil_spock.jpgmirror universe SpockThe evil mirror-universe Mr. Spock, from the original series episode "Mirror, Mirror". The beard is obviously a sign of his evilness, which means somewhere in a parallel universe there's a good version of me, who is clean-shaven. [Credit: CBS Studios]2013-08-18T16:12:09+00:00monthlyhttps://galileospendulum.org/2013/08/16/albert-einstein-vs-the-universe/https://galileospendulum.org/wp-content/uploads/2013/08/einsteins_greatest_blender.jpgEinstein's greatest blenderEinstein's greatest blender. [Credit: BBJ on Flickr]2013-08-28T18:47:00+00:00monthlyhttps://galileospendulum.org/2013/08/14/mapping-a-black-holes-magnetic-field-using-a-pulsar/2013-08-14T18:39:25+00:00monthlyhttps://galileospendulum.org/2013/08/12/that-durned-schrodingers-cat/https://galileospendulum.org/wp-content/uploads/2013/08/smbc_schrodingers_cat.gifSchrodinger's cat, in comics[Click for the full-sized comic. Credit: Zach Weinersmith]2013-08-12T17:18:58+00:00monthlyhttps://galileospendulum.org/2013/08/09/its-a-great-big-universe-and-were-all-really-puny/https://galileospendulum.org/wp-content/uploads/2013/08/too_big_for_small_talk.pngThis message brought to you by the Society of Astronomers Trapped on the Surface of a Sphere.[Credit: Randall Munroe]https://galileospendulum.org/wp-content/uploads/2013/08/blow_circuits_at_nasa.jpgCalvin & Hobbes on MarsThe first completely undoctored image taken by the Mars Curiosity rover upon its landing last year.2013-08-09T16:39:56+00:00monthlyhttps://galileospendulum.org/2013/08/05/no-this-new-theory-does-not-cast-doubt-on-dark-matter/2013-08-29T10:21:50+00:00monthlyhttps://galileospendulum.org/2013/07/31/will-we-ever-have-reliable-nuclear-fusion-power/2013-07-30T19:49:41+00:00monthlyhttps://galileospendulum.org/2012/07/11/arsenic-life-cold-fusion-and-the-allure-of-wishful-thinking/2013-07-30T19:47:38+00:00monthlyhttps://galileospendulum.org/2013/07/30/of-neutrino-oscillations-and-coming-full-circle/2013-07-30T17:21:29+00:00monthlyhttps://galileospendulum.org/2013/07/28/lets-raise-the-bar-and-our-cups-to-the-stars/2013-07-29T02:10:51+00:00monthlyhttps://galileospendulum.org/2013/07/26/what-if-photons-actually-have-mass/https://galileospendulum.org/wp-content/uploads/2013/07/coulomb.pngCoulombhttps://galileospendulum.org/wp-content/uploads/2013/07/photon_mass.pngphoton_masshttps://galileospendulum.org/wp-content/uploads/2013/07/yukawa.pngYukawahttps://galileospendulum.org/wp-content/uploads/2013/07/cmb_intensity.jpgCMB blackbody spectrumThe cosmic microwave background (CMB) shows that the Universe is nearly a perfect blackbody. The pink dotted curve is the spectrum as predicted by theory, while the various other colored points are measurements by several observatories over 20 years. Note that the frequency range on the horizontal axis runs over a huge range, showing how well the CMB matches the blackbody spectrum. [Credit: http://ned.ipac.caltech.edu/level5/Sept05/Gawiser2/Gawiser2.html ]2013-08-01T11:52:24+00:00monthlyhttps://galileospendulum.org/2013/07/22/will-we-ever-create-a-black-hole-in-the-laboratory/https://galileospendulum.org/wp-content/uploads/2013/07/black-hole-event-atlas.pngsimulated event creating a black hole Simulation of a collision at the LHC producing a mini-black hole. No such event has occurred so far, but what if we could make a tiny black hole in the lab? [Credit ATLAS Experiment © 2013 CERN]2013-07-22T16:52:05+00:00monthlyhttps://galileospendulum.org/2013/07/20/the-view-from-saturn-and-beyond/https://galileospendulum.org/wp-content/uploads/2013/07/neptune_new_moon.jpgNeptune's newly discovered moonNeptune's newly discovered moon, found in archival Hubble Space Telescope data. [Credit: NASA, ESA, and M. Showalter (SETI Institute)]https://galileospendulum.org/wp-content/uploads/2013/07/wave_at_saturn_adjusted.jpgwaving at SaturnWaving at Saturn with the Richmond Astronomical Society and other science fans, at the Science Museum of Virginia. Both the time and the extreme heat were against us, but the group was really enthusiastic. [Credit: moi]2013-07-20T16:02:16+00:00monthlyhttps://galileospendulum.org/2012/06/04/moonday-tides-of-doom/https://galileospendulum.org/wp-content/uploads/2012/06/triton_comparison.pngTriton's size compared to Earth and the MoonTriton's size compared to Earth and the Moon.https://galileospendulum.org/wp-content/uploads/2012/06/triton_cantaloupe.jpgcantaloupe terrain on TritonA detailed Voyager 2 image of cantaloupe terrain on Triton. This strange feature is free of craters, but exactly why it appears the way it does is mysterious.https://galileospendulum.org/wp-content/uploads/2012/06/triton_post.jpgTriton, Neptune's largest moonTriton, Neptune's largest moon, as seen by Voyager 2. The surface is water, methane, and ammonia ice, renewed by cryovolcanism: ice volcanoes analogous to what we see on Saturn's moon Enceladus.2013-07-20T15:47:03+00:00monthlyhttps://galileospendulum.org/2013/07/19/above-the-carbon-monoxide-snow-line-in-a-young-star-system/2013-07-19T16:10:48+00:00monthlyhttps://galileospendulum.org/2013/07/18/colliding-neutron-stars-could-make-heavy-nuclei/2013-07-20T10:03:51+00:00monthlyhttps://galileospendulum.org/2013/07/17/please-dont-use-dark-matter-to-mean-something-we-dont-understand/https://galileospendulum.org/wp-content/uploads/2013/07/dark_matter_genome.pngGoogle found dark matterThe first few hits when I searched for "dark matter genome" on Google.2013-07-19T00:09:10+00:00monthlyhttps://galileospendulum.org/2013/07/17/the-day-earth-smiled/2013-07-17T23:22:53+00:00monthlyhttps://galileospendulum.org/2013/07/12/a-beautiful-metaphorical-death/https://galileospendulum.org/wp-content/uploads/2013/07/ngc2392.jpgNGC 2392The death of a star much like our Sun is a thing of beauty. This is the nebula NGC 2392, as imaged in visible light and X-rays (the pink colors). [Credit: X-ray: NASA/CXC/IAA-CSIC/N.Ruiz et al, Optical: NASA/STScI]2013-07-13T11:10:19+00:00monthlyhttps://galileospendulum.org/2013/07/09/the-truth-is-out-there-about-aliens/https://galileospendulum.org/wp-content/uploads/2013/07/xkcd_settled.pngWell, we've really only settled the question of ghosts that emit or reflect visible light. Or move objects around. Or make any kind of sound. But that covers all the ones that appear in Ghostbusters, so I think we're good.Credit: Randall Munroe2013-07-09T23:12:05+00:00monthlyhttps://galileospendulum.org/2013/07/08/what-is-weight/https://galileospendulum.org/wp-content/uploads/2013/07/orbital_gravity.pnggravity strength as a function of altitudeThe strength of gravity as a function of altitude above Earth's surface. The ISS orbits at 370 km altitude, where the gravitational strength is about 90% of its value at the surface - hardly zero gravity!https://galileospendulum.org/wp-content/uploads/2013/07/chris_hadfield.jpgChris Hadfield on the ISSCanadian astronaut Chris Hadfield aboard the International Space Station (ISS), demonstrating weightlessness with tomatoes. [Credit: International Business Times]2013-07-09T12:41:22+00:00monthlyhttps://galileospendulum.org/2012/07/04/higgsdependence-day/2013-07-04T14:02:14+00:00monthlyhttps://galileospendulum.org/2012/05/08/the-higgs-boson-in-theory-and-in-experiment/2013-07-04T14:01:59+00:00monthlyhttps://galileospendulum.org/2013/07/03/our-higgs/https://galileospendulum.org/wp-content/uploads/2013/07/higgs_mechanism.pngHiggs mechanism in Comic SansOne version of the Higgs mechanism explaining how some particles acquire mass, typeset in Comic Sans. What, do I have to have a reason?https://galileospendulum.org/wp-content/uploads/2013/07/pheno2013_small.jpgPheno2013 attendeesAttendees of the Phenomenology 2013 symposium at the University of Pittsburgh. Look for the bowler hat.... [Credit: the website doesn't list a photographer name, so please help if you can]https://galileospendulum.org/wp-content/uploads/2013/07/comichiggs.pngComic Sans HiggsOne version of the Higgs mechanism explaining how some particles acquire mass, typeset in Comic Sans. What, do I have to have a reason?2013-07-04T10:54:12+00:00monthlyhttps://galileospendulum.org/2013/07/01/open-letter-to-the-washington-post/https://galileospendulum.org/wp-content/uploads/2013/07/jupiter_in_gemini.pngJupiter's position in the skyJupiter isn't in Cancer this month, it's in Gemini. This is the star chart I created this morning using Stellarium, a freely available planetarium program. Not only is Jupiter not in Cancer, it's closer to the far side of Gemini, nearly in the next Zodiac constellation.https://galileospendulum.org/wp-content/uploads/2013/07/signature.pngsignature2013-07-01T20:10:05+00:00monthlyhttps://galileospendulum.org/2013/06/28/some-brief-notes/https://galileospendulum.org/wp-content/uploads/2013/06/harriet_scary_eyes_small.jpgHarriet the catHarriet the cat will shoot you with her laser eyes.https://galileospendulum.org/wp-content/uploads/2013/06/harriet_scary_eyes.jpgHarriet the catHarriet the cat will shoot you with her laser eyes.2013-06-28T19:24:42+00:00monthlyhttps://galileospendulum.org/2013/06/17/felicia-the-fermilab-ferret/https://galileospendulum.org/wp-content/uploads/2013/06/felicia_fermilab_ferret.jpgFelicia the Fermilab ferretFelicia the Fermilab Ferret. [Foto by fTim Fielding, Fermi fNational fAccelerator fLaboratory.]2013-06-17T14:06:39+00:00monthlyhttps://galileospendulum.org/2013/06/15/testing-the-mass-energy-relationship/https://galileospendulum.org/wp-content/uploads/2013/06/penning_trap.jpgPenning trapA Penning trap, used to measure the masses of ions and other electrically charged particles. [Credit: Imperial College]https://galileospendulum.org/wp-content/uploads/2013/06/silicon_reaction.pngsilicon_reactionhttps://galileospendulum.org/wp-content/uploads/2013/06/sulfur_reaction.pngsulfur_reaction2013-06-16T22:21:33+00:00monthlyhttps://galileospendulum.org/2013/06/09/the-genius-and-the-damage-done/2013-06-09T21:10:53+00:00monthlyhttps://galileospendulum.org/2013/06/07/so-whats-all-the-fuss-about-bayesian-statistics/https://galileospendulum.org/wp-content/uploads/2013/06/bayes_final.pngBayes_finalhttps://galileospendulum.org/wp-content/uploads/2013/06/bayes_likelihood3.pngBayes_likelihood3https://galileospendulum.org/wp-content/uploads/2013/06/bayes_identical.pngBayes_identicalhttps://galileospendulum.org/wp-content/uploads/2013/06/bayes_prior2.pngBayes_prior2https://galileospendulum.org/wp-content/uploads/2013/06/bayes_likelihood.pngBayes_likelihoodhttps://galileospendulum.org/wp-content/uploads/2013/06/bayes_prior1.pngBayes_prior1https://galileospendulum.org/wp-content/uploads/2013/06/bayes_pieces.pngBayes_pieceshttps://galileospendulum.org/wp-content/uploads/2013/06/bayes_jaynes_form.pngBayes_Jaynes_formhttps://galileospendulum.org/wp-content/uploads/2013/06/thomas_bayes.gifprobably not Thomas BayesThis is probably not Thomas Bayes, but it's the picture we all use for him anyway. [Source: Wikipedia]2013-06-07T23:41:36+00:00monthlyhttps://galileospendulum.org/2013/06/02/cracking-jokes-about-uranus-makes-you-look-like-an/https://galileospendulum.org/wp-content/uploads/2013/06/uranus_lakdawalla.jpgcrescent Uranus from Voyager 2The planet Uranus as seen by Voyager 2 about a week after its flyby. Click the image for more information on how the image was created. [Credit: NASA / JPL / Emily Lakdawalla]2013-06-04T10:06:17+00:00monthlyhttps://galileospendulum.org/2012/10/04/1001-mind-blowing-facts-about-yo-momma/2013-06-01T15:56:22+00:00monthlyhttps://galileospendulum.org/2013/05/31/asteroid-moon-moonsteroid/https://galileospendulum.org/wp-content/uploads/2013/05/qe2_moon.png1998 QE2 and moonThe asteroid 1998 QE2 and its tiny moon visible as a brighter spot below the larger gray blur that's the asteroid. [Credit: NASA/JPL]2013-06-01T12:28:44+00:00monthlyhttps://galileospendulum.org/2013/05/30/how-a-dark-matter-signal-can-vanish/https://galileospendulum.org/wp-content/uploads/2013/05/fermi_all_sky.jpgFermi all-sky mapMap of the sky in gamma-ray light, by the Fermi Gamma-Ray Observatory's Large Area Telescope (LAT). [Credit: NASA/DOE/International LAT Team]https://galileospendulum.org/wp-content/uploads/2013/05/gamma_ray_energy.pnggamma_ray_energyhttps://galileospendulum.org/wp-content/uploads/2013/05/dm_annihilation.pngDM_annihilation2013-06-16T10:10:42+00:00monthlyhttps://galileospendulum.org/2013/05/28/the-meaning-of-mass/https://galileospendulum.org/wp-content/uploads/2013/05/albert_einstein.jpgAlbert EinsteinAlbert Einstein as a young man, before his crazy-hair days. (Credit: Lucien Chavan, public domain)https://galileospendulum.org/wp-content/uploads/2013/05/photon.pngphotonhttps://galileospendulum.org/wp-content/uploads/2013/05/rearranged.pngrearrangedhttps://galileospendulum.org/wp-content/uploads/2013/05/einstein_equation1.pngEinstein_equationhttps://galileospendulum.org/wp-content/uploads/2013/05/full_equation.pngfull_equationhttps://galileospendulum.org/wp-content/uploads/2013/05/einstein_equation.pngEinstein_equation2013-05-29T12:43:14+00:00monthlyhttps://galileospendulum.org/2013/05/27/did-einstein-write-his-most-famous-equation-does-it-matter/https://galileospendulum.org/wp-content/uploads/2013/05/relativity-of-cats.jpgrelativity books, with catsA small representative sample of my relativity books, with my cats Pascal and Harriet for scale.https://galileospendulum.org/wp-content/uploads/2013/05/einstein_fig2.pngTranscription of a blackboard from Einstein's 1934 talkEinstein's most famous equation, sort of. This is the transcription of the chalkboard from a public talk Einstein gave in Pittsburgh in 1934. (Credit: Dwight Vincent and David Topper)https://galileospendulum.org/wp-content/uploads/2013/05/einstein_1934_top.jpgAlbert Einstein in 1934Albert Einstein in Pittsburgh, 1934. Note that the blackboard is covered with equations of relativity, which are its most accurate expression. [Credit: Pittsburgh Sun-Telegraph/Dwight Vincent and David Topper]2013-05-27T13:35:28+00:00monthlyhttps://galileospendulum.org/2013/05/17/new-beer-for-planet-hunters/https://galileospendulum.org/wp-content/uploads/2013/05/frame055.pngsimulation of beamingSimulation of relativistic beaming, for a star moving to the right (relative to us) at 55% of light-speed. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2013/05/doppler2.pngDoppler effectThe Doppler effect occurs when the source and observer of light are traveling at different speeds relative to each other. The source's light will be pushed to shorter wavelengths — blueshifted — if it's moving toward you, and stretched longer — redshifted — if it's moving away.2013-05-17T15:24:13+00:00monthlyhttps://galileospendulum.org/2013/05/09/will-we-ever-know-what-happened-before-the-big-bang/2013-09-14T09:34:27+00:00monthlyhttps://galileospendulum.org/2013/05/02/einstein-must-mean-a-really-stupid-person/https://galileospendulum.org/wp-content/uploads/2013/05/such_an_einstein.pngCul de Sac comic"Cul de Sac" comic by Richard Thompson2013-05-05T18:56:52+00:00monthlyhttps://galileospendulum.org/2013/04/29/of-aquatic-apes-and-ignorant-congressmen/2013-04-30T16:09:33+00:00monthlyhttps://galileospendulum.org/2013/04/20/shadows-and-light/https://galileospendulum.org/wp-content/uploads/2013/04/horsehead_ir_visible.jpgHorsehead nebula in visible and infraredThe Horsehead Nebula in both infrared (left) and visible light. [Credit: NASA, ESA, and the Hubble Heritage Team (AURA/STScI); ESO]https://galileospendulum.org/wp-content/uploads/2013/04/horsehead_nebula_small.jpgHorsehead nebula in visible and infraredThe Horsehead nebula, in both visible and infrared light. [Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)]2013-04-20T19:13:25+00:00monthlyhttps://galileospendulum.org/2013/04/16/of-dark-matter-and-hope/https://galileospendulum.org/wp-content/uploads/2013/04/cdms.jpgthe room inside the room where CDMS sitsYou'll have to take my word for it that CDMS sits inside the room behind the glass in this photo. [Credit: moi]2013-04-17T09:29:09+00:00monthlyhttps://galileospendulum.org/2013/04/12/green-peas-blue-stars-and-ultraviolet-light/https://galileospendulum.org/wp-content/uploads/2013/04/blackbody.pngthermal spectraEmission spectra of light for objects with various surface temperatures. Our Sun is most like the the hottest one, labeled with the green curve. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2013/04/green_pea_galaxy.jpgA Green Pea galaxyA Green Pea galaxy. [Credit: SDSS]2013-04-12T19:02:57+00:00monthlyhttps://galileospendulum.org/2013/04/08/talk-mathy-to-me-whats-the-square-root-of-i/https://galileospendulum.org/wp-content/uploads/2013/04/i_to_i.pngi_to_ihttps://galileospendulum.org/wp-content/uploads/2013/04/general_root.pnggeneral_roothttps://galileospendulum.org/wp-content/uploads/2013/04/other_i_root.pngother_i_roothttps://galileospendulum.org/wp-content/uploads/2013/04/other_neg_root.pngother_neg_roothttps://galileospendulum.org/wp-content/uploads/2013/04/negative_root.pngnegative_roothttps://galileospendulum.org/wp-content/uploads/2013/04/duh.pngduhhttps://galileospendulum.org/wp-content/uploads/2013/04/root_of_i.pngsquare root of iThe square root of i is just another clockwise rotation, halving the phase angle.https://galileospendulum.org/wp-content/uploads/2013/04/sqrt_i.pngsqrt_ihttps://galileospendulum.org/wp-content/uploads/2013/04/square_root.pngtaking the square root of -1Taking the square root of -1 is the equivalent of rotating the circle by 90 degrees, or (more appropriately) pi/2.https://galileospendulum.org/wp-content/uploads/2013/04/euler_root.pngeuler_root2013-09-24T14:53:16+00:00monthlyhttps://galileospendulum.org/2012/06/12/a-moment-of-science/https://galileospendulum.org/wp-content/uploads/2012/06/stm_racetrack.jpg"racetrack" of atoms"Racetrack" of iron atoms deposited on a copper surface. The image was formed by measuring the electron's electric fields using a scanning tunneling electron microscope. [Credit: IBM]2013-04-07T13:39:27+00:00monthlyhttps://galileospendulum.org/2013/04/04/no-there-are-no-hints-of-dark-matter-in-new-experimental-results/https://galileospendulum.org/wp-content/uploads/2013/04/ams_power_spectrum.jpgExcess of positrons as a function of energyThis plot shows the excess of positrons as a function of their energy. The red dots are from AMS-02, while the other colors represent data from other detectors. [Credit: AMS collaboration]2013-04-05T11:45:20+00:00monthlyhttps://galileospendulum.org/2013/03/29/equality-mathematical-and-practical/https://galileospendulum.org/wp-content/uploads/2013/03/equality_pi.pngpi for equalityPi for equality.2013-03-30T23:56:53+00:00monthlyhttps://galileospendulum.org/2013/03/26/will-we-ever-detect-gravitational-waves-directly/https://galileospendulum.org/wp-content/uploads/2013/03/gw_detector.pngbehavior of a gravitational wave detectorHere's a simple representation of gravitational waves, from a binary system consisting of equal-mass pulsars. If we're viewing the system "face-on", the wave will cause a ring of particles to distort aligned with the orientation of the pulsars. Charlie Brown's head (which is not an approved gravitational wave detector) wouldn't actually distort this much because the internal forces are much stronger than gravity. However, if we constructed a detector with movable mirrors, they could play a similar role. [Credit: moi/Charles Schulz]https://galileospendulum.org/wp-content/uploads/2013/03/ligo3.jpgmirror assembly at LIGOA portion of the mirror assembly at LIGO, consisting of three sections that can move like pendulums. Having three sections means the lowest portion - which the mirror itself - moves relatively little when seismic waves hit it. What remains should be (at least partly) due to gravitational waves. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2013/03/ligo2.jpgarm of LIGOOne portion of the LIGO gravitational wave detector, located in Louisiana. [Credit: moi]2013-03-29T14:07:54+00:00monthlyhttps://galileospendulum.org/2013/03/24/forget-the-paleo-diet-how-about-the-mesozoic-diet/https://galileospendulum.org/wp-content/uploads/2013/03/sauropod-pancake.jpgsauropod pancakeA pancake shaped like a sauropod.2013-03-24T19:18:31+00:00monthlyhttps://galileospendulum.org/2013/03/21/planck-results-our-weird-and-wonderful-universe/https://galileospendulum.org/wp-content/uploads/2013/03/planck_peaks1.pnghighlights in the CMB power spectrumA few highlights in the CMB power spectrum. a. The third peak indicates the total matter content of the Universe, both baryonic (ordinary) and dark. Planck has much better data for this peak than WMAP, strengthening the case for dark matter's existence and how much of it there is in the Universe. b. The long tail of smaller peaks is the small-scale fluctuations that gave birth to galaxies at later times. Awesome, right? c. The anomalous temperature fluctuations at the largest scales, first seen by WMAP in 2001, are probably the things getting the most attention today. [Credit: ESA/Planck Collaboration/moi]https://galileospendulum.org/wp-content/uploads/2013/03/planck_power_spectrum_small.pngPlanck CMB Power SpectrumThe Planck CMB power spectrum, which represents the temperature fluctuations (vertical axis) as a function of size on the sky (horizontal). The temperature fluctuations are squared because we don't care at the moment if they're hotter or colder than average - we're just after how much they deviate. The horizontal scale runs from 90 degrees - one quarter of the way around the sky - down to a tiny fraction of a degree, much smaller than the full Moon, which is half a degree on the sky. [Credit: ESA/Planck Collaboration]https://galileospendulum.org/wp-content/uploads/2013/03/planck_cmb.pngPlanck CMB mapIf you think theories about the universe are mind-bending, rest assured that many scientists feel the same way. But the question isn't a philosophical one: it has potentially real, testable aspects. [Credit: ESA/Planck Collaboration/D. Ducros]https://galileospendulum.org/wp-content/uploads/2013/03/planck_cosmic_recipe_vertical.pngthe cosmic pie, before and after PlanckThe cosmic pie, before and after Planck. The size of the slices changed a little bit, but it's barely noticeable. [Credit: ESA/Planck Collaboration]2013-04-13T23:42:08+00:00monthlyhttps://galileospendulum.org/2013/03/15/oh-geez-not-another-exoplanet-story/https://galileospendulum.org/wp-content/uploads/2013/03/exoplanet_image.jpgimage of exoplanets in the HR 8799 systemImage of exoplanets in the HR 8799 system, from the Keck telescope in Hawaii. [Credit: RC-HIA/C. Marois/Keck Observatory]2013-03-16T16:25:29+00:00monthlyhttps://galileospendulum.org/2013/03/11/d-is-for-dark-energy-alphabet-of-cosmology/https://galileospendulum.org/wp-content/uploads/2013/03/decam_ceiling.pngtest rig for DECamThe test rig for the Dark Energy Camera (DECam) at Fermilab. I picked this image today because it kinda sorta looks like the wormhole-making machine from the film version of Contact. [Credit: moi]https://galileospendulum.org/wp-content/uploads/2013/03/quark_panel.pngpanel from "Calvin and Hobbes"If you don't know Calvin & Hobbes, we are no longer friends.2013-04-01T21:50:51+00:00monthlyhttps://galileospendulum.org/2013/03/04/learning-science-communication-from-baseball-players/https://galileospendulum.org/wp-content/uploads/2013/03/ndt_and_me.jpgme and my close personal friend, Neil deGrasse TysonMe and my close personal friend, Neil deGrasse Tyson. [Credit: Patrick Queen/photographic fakery]2013-03-11T19:27:29+00:00monthlyhttps://galileospendulum.org/2013/03/01/will-we-ever-understand-what-dark-matter-is-made-from/2013-03-01T13:30:26+00:00monthlyhttps://galileospendulum.org/2013/01/30/the-never-ending-adventure-that-is-life/https://galileospendulum.org/wp-content/uploads/2013/01/photo-on-1-30-13-at-3-04-pm.jpginjured pawA dawg dun bit me.2013-02-28T20:26:11+00:00monthlyhttps://galileospendulum.org/2013/02/28/c-is-for-cosmic-microwave-background-alphabet-of-cosmology/https://galileospendulum.org/wp-content/uploads/2013/02/wmap_9year_pie.pngthe major contents of the UniverseThe major components of the Universe, based on WMAP and other data. Baryonic matter (called "atoms" on the graph) is only 4.5% of the total energy density of the cosmos. Dark energy and dark matter comprise most of the rest. Photons, neutrinos, and other components contribute too little to be seen. [Credit: NASA/WMAP Science Team]https://galileospendulum.org/wp-content/uploads/2013/02/wmap_peaks.pngCMB power spectrumThe cosmic microwave background (CMB) power spectrum, using 7 years of data from the Wilkinson Microwave Anisotropy Probe (WMAP). The location of each of the labeled peaks reveals something about the composition and geometry of the Universe. [Credit: NASA/WMAP Science Team]2013-04-17T16:23:10+00:00monthlyhttps://galileospendulum.org/2013/02/20/busy-is-my-best-friend/2013-02-26T19:23:16+00:00monthlyhttps://galileospendulum.org/2013/02/25/was-weaker-gravity-responsible-for-large-dinosaur-size/https://galileospendulum.org/wp-content/uploads/2013/02/geoids_grace.jpggeoids from GRACE missionEastern and western hemisphere geoids: variations of the Earth's gravitational influence, as measured by the GRACE satellites. The lumps and colors both indicate deviations from the average, with blue indicating slightly stronger gravity, and red indicating slightly weaker. [Credit: NASA/EOS]https://galileospendulum.org/wp-content/uploads/2013/02/surface_area.pngsurface_areahttps://galileospendulum.org/wp-content/uploads/2013/02/ratio.pngratiohttps://galileospendulum.org/wp-content/uploads/2013/02/law_of_gravity.pnglaw_of_gravityhttps://galileospendulum.org/wp-content/uploads/2013/02/latin-love-god-with-supersaurus.jpegsauropod vertebra fragment, with paleontologist for scaleA piece of a Supersaurus vertebra, with paleontologist glamor for reference. While no other part of Supersaurus has been found yet, the shape of the bone identifies it as a sauropod, and the size of the fragment (that's not the whole vertebra!) marks it probably as the largest land animal that ever lived. [Credit: Sauropod Vertebra Picture of the Week/Mike Taylor]2013-10-26T14:44:18+00:00monthlyhttps://galileospendulum.org/2013/02/12/on-dinosaurs-and-darwin/https://galileospendulum.org/wp-content/uploads/2013/02/christmas_card_by_themorlock.pngGorgosaurus hen and chicksChristmas card depicting a Gorgosaurus hen and chicks in the snow. [Credit: TheMorlock]2013-02-24T12:37:41+00:00monthlyhttps://galileospendulum.org/2013/02/22/b-is-for-baryon-acoustic-oscillations-alphabet-of-cosmology/https://galileospendulum.org/wp-content/uploads/2013/02/boss_template.pngMask for BOSSOne of the aluminum plates used in the BOSS survey. Each hole in the plate corresponds to the position of a galaxy. Light from that galaxy then passes through the hole into a fiber optic cable, where its spectrum can be analyzed. The plate blocks out light from everything else, keeping the signal as clean as possible. [Credit: moi]2013-02-22T14:21:44+00:00monthlyhttps://galileospendulum.org/2011/08/16/i-call-on-the-resting-soul-of-galileo-to-whup-your-behind/2013-02-16T16:36:30+00:00monthlyhttps://galileospendulum.org/2013/02/15/dont-panic-but-be-prepared/2013-02-15T16:22:17+00:00monthlyhttps://galileospendulum.org/2013/02/06/now-is-the-winter-of-our-discontent-made-glorious-summer/2013-02-07T15:36:35+00:00monthlyhttps://galileospendulum.org/2013/02/06/in-defense-of-jargon-and-expertise/2013-02-10T14:21:38+00:00monthlyhttps://galileospendulum.org/2013/01/27/spillover-and-the-silence/https://galileospendulum.org/wp-content/uploads/2013/01/silence.jpgThe Silence from Doctor WhoThe Silence from Doctor Who.2013-01-29T18:51:06+00:00monthlyhttps://galileospendulum.org/2013/01/25/a-is-for-axion-alphabet-of-cosmology/https://galileospendulum.org/wp-content/uploads/2013/01/admx.jpgADMXThe ADMX axion detector at the University of Washington. [Credit: ADMX collaboration]2013-01-26T20:43:31+00:00monthlyhttps://galileospendulum.org/2013/01/19/my-hands-felt-just-like-two-balloons/https://galileospendulum.org/wp-content/uploads/2013/01/crater_illusion.jpgcrater illusionA well-known optical illusion can be produced from images of craters or similar structures. The top and bottom photo are the same picture, just oriented differently. [Credit: I don't remember where I got this image! If anyone can identify it, please let me know]2013-01-19T16:51:53+00:00monthlyhttps://galileospendulum.org/2013/01/18/do-you-realize-everyone-you-know-one-day-will-die/2013-01-18T20:45:09+00:00monthlyhttps://galileospendulum.org/2013/01/11/the-blues-of-supernovas-the-standard-candles-of-jazz/https://galileospendulum.org/wp-content/uploads/2013/01/mingus_supernova.jpga supernova called MingusA supernova called Mingus, after the jazz composer and bassist. The supernova was recently announced to be the most distant white dwarf (Type Ia) supernova yet discovered. [Credit: Space Telescope Science Institute]2013-01-11T15:44:32+00:00monthlyhttps://galileospendulum.org/2013/01/10/on-negative-temperatures-negative-pressures-and-maybe-dark-energy/https://galileospendulum.org/wp-content/uploads/2013/01/energy_temperature.pngenergy and temperature in an ideal paramagnetThe temperature as a function of energy in our ideal paramagnet. Notice that absolute zero is still inaccessible! You can't cool down the magnet to zero. However, the states where more spins are down than up - the right side of the graph - want to give up energy to reach maximum entropy. That corresponds to negative absolute temperature.https://galileospendulum.org/wp-content/uploads/2013/01/energy_entropy.pngenergy and entropy in paramagnetic materialEntropy as a function of energy in an ideal paramagnet. For simplicity, I made the maximum entropy correspond to zero energy (since what matters is energy differences, not the absolute number for energy).https://galileospendulum.org/wp-content/uploads/2013/01/xkcd_converting_to_metric_temp.pngxkcd comic - click for the whole thingA portion of an xkcd comic, dealing with intuitive temperature measurements. Click for the rest of the comic (which deals with length, mass, and so forth). Warning: contains swears.2013-03-29T20:12:41+00:00monthlyhttps://galileospendulum.org/2013/01/08/a-brief-update/https://galileospendulum.org/wp-content/uploads/2013/01/het_afar_snap.jpgHobby-Eberly TelescopeThe Hobby-Eberly Telescope (HET) at McDonald Observatory in western Texas, seen from an adjacent mountain. [Credit: moi]2013-01-08T18:31:09+00:00monthlyhttps://galileospendulum.org/2013/01/05/if-it-wasnt-for-disappointment-i-wouldnt-have-any-appointments/2013-01-07T00:51:19+00:00monthlyhttps://galileospendulum.org/2012/12/28/scientific-debates-are-mostly-a-waste-of-time/https://galileospendulum.org/wp-content/uploads/2012/12/grb.jpgGRB 100621AThe gamma ray burst GRB 100621A, discovered in 2010. GRBs are some of the brightest objects in the entire Universe, outshining everything else put together during their brief periods of brightest activity. For many years, however, astronomers debated whether they were local objects in our galaxy, or very distant. The latter answer turned out to be correct, based on many years of hard work. [Credit: NASA/Swift/Stefan Immler]https://galileospendulum.org/wp-content/uploads/2012/12/astrophysiological_journal.pngAstrophysiological JourneyThe fake table of contents from the April 1, 1986 issue of the Astrophysical Journal. (Click for larger version.)2012-12-30T01:24:42+00:00monthlyhttps://galileospendulum.org/2012/12/25/my-gift-to-you-science-christmas/https://galileospendulum.org/wp-content/uploads/2012/12/multiwavelength_universe_small.pngthe multiwavelength UniverseThe multicolored Universe. Click for the larger version. [Credit: moi (mosaic); see below for others]2012-12-26T04:25:11+00:00monthlyhttps://galileospendulum.org/2012/12/24/silent-night-science-advent-23/https://galileospendulum.org/wp-content/uploads/2012/12/black_marble.jpgthree views of Earth at nightThe Black Marble: three views of Earth at night. Left: the Americas; center: Europe, Africa, the Middle East; right: Asia and Australia. [Credit: NASA Earth Observatory]2012-12-24T14:38:59+00:00monthlyhttps://galileospendulum.org/2012/12/23/a-distant-twin-science-advent-22/https://galileospendulum.org/wp-content/uploads/2012/12/ugc_12158.jpgspiral galaxy UGC 12158The large spiral galaxy UGC 12158 is remarkably similar to the Milky Way in many ways. Though it's a lot bigger, the galaxy shares many features with our galactic home: the strong spiral arms and long bar structure running through the center. [Credit: ESA/Hubble & NASA]2012-12-25T21:00:06+00:00monthlyhttps://galileospendulum.org/2012/12/22/a-white-dwarf-in-a-lab-science-advent-21/https://galileospendulum.org/wp-content/uploads/2012/12/z-machine.jpgthe Z-machineThe Z-machine at Sandia National Laboratory in Albuquerque, New Mexico (don't make a wrong turn there!) uses intense pulses of electrical energy to make gamma rays and X-rays. These in turn are used to study nuclear fusion - and to simulate certain astrophysical systems, like white dwarfs. [Credit: Sandia Corporation]2012-12-22T15:35:30+00:00monthlyhttps://galileospendulum.org/2012/12/21/solace-on-the-solstice-science-advent-20/https://galileospendulum.org/wp-content/uploads/2012/12/stonehenge1_small.jpgStonehengeThe giant prehistoric stone ring known as Stonehenge was built in part as a solar calendar, with stones aligned with the rising and setting of the Sun and the brightest star Sirius on significant days of the year. Today marks one such day: the northern winter solstice, which is the shortest day of the year in the northern hemisphere. [Credit: moi]2012-12-21T13:44:18+00:00monthlyhttps://galileospendulum.org/2012/12/20/an-eclipse-of-extraordinary-beauty-science-advent-19/https://galileospendulum.org/wp-content/uploads/2012/12/saturn_eclipse_2012.pngSaturn in eclipseSince Saturn is farther from the Sun than Earth, we never see it in eclipse: when it blocks the Sun. However, the Cassini spacecraft sometimes passes in such a way that the planet is between it and the Sun, which is the source of today's image. [Credit: NASA/JPL-Caltech/SSI]2012-12-20T15:40:52+00:00monthlyhttps://galileospendulum.org/2012/12/19/a-stellar-shock-wave-science-advent-18/https://galileospendulum.org/wp-content/uploads/2012/12/zeta_ophiuchi.jpggiant star Zeta Ophiuchi and its shock waveThe giant star Zeta Ophiuchi is moving rapidly enough through a cloud of dust to raise a shock wave - a stellar sonic boom. This image was made using infrared light, which both punches through cosmic dust (which is opaque to visible light) and shows where the dust glows when it is heated. [Credit: NASA/JPL-Caltech]2012-12-19T14:32:35+00:00monthlyhttps://galileospendulum.org/2012/12/18/a-high-energy-microscope-science-advent-17/https://galileospendulum.org/wp-content/uploads/2012/12/cdf_partly_open.jpgCDF - collider detector at FermilabThe inside of the Collider Detector at Fermilab (CDF). Protons and antiprotons enter the detector from opposite directions, via the thin gray pipe barely visible at the image center. During collisions, these particles dissolve into their constituent quarks and (since this is quantum physics) many other things. [Credit: moi]2012-12-18T14:22:50+00:00monthlyhttps://galileospendulum.org/2012/12/17/end-of-the-grail-quest-science-advent-16/https://galileospendulum.org/wp-content/uploads/2012/12/grail_topography.jpgdensity map of Moon from GRAILA map of Earth's Moon, using gravitational data from the twin GRAIL spacecraft. The GRAIL mission ends today, when the spacecraft will be deliberately crashed into a lunar mountain. [Credit: NASA/JPL-Caltech/ IPGP]2012-12-17T14:35:12+00:00monthlyhttps://galileospendulum.org/2012/12/16/a-galaxy-exploded-science-advent-15/https://galileospendulum.org/wp-content/uploads/2012/12/cartwheel.jpgCartwheel GalaxyApproximately 200 million years before this image, a smaller galaxy burst through the disk of the blue ring of galaxy at the left. The result is the Cartwheel Galaxy. The blue light at the galaxy's rim marks the formation of new stars, catalyzed by the collision. [Credit: NASA/ESA/K. Borne (STScI)]2012-12-16T15:05:36+00:00monthlyhttps://galileospendulum.org/2012/12/15/little-round-planet-in-a-big-universe-science-advent-14/https://galileospendulum.org/wp-content/uploads/2012/12/blue_marble.pngBlue MarbleThe blue marble, our home, as seen by the Suomi NPP satellite. [Credit: NASA/Norman Kuring]2012-12-15T14:39:05+00:00monthlyhttps://galileospendulum.org/2012/12/14/astronomy-without-light-science-advent-13/https://galileospendulum.org/wp-content/uploads/2012/12/sun_in_neutrinos.jpgthe Sun in neutrinosThis image is the Sun, but it wasn't created using light. In addition to photons, the Sun also emits a huge number of neutrinos, very low-mass particles produced by nuclear fusion in the Sun's core. [Credit: Kamioka Observatory/ICRR/Univ. of Tokyo]2012-12-14T14:07:28+00:00monthlyhttps://galileospendulum.org/2012/12/13/a-titanic-river-science-advent-12/https://galileospendulum.org/wp-content/uploads/2012/12/titan_s_nile_river.pnga river on TitanA newly discovered river on Saturn's moon, Titan. The course of the river is fairly straight, so it's probable that it follows a rift. [Credit: NASA/JPL–Caltech/ASI]2012-12-14T14:06:25+00:00monthlyhttps://galileospendulum.org/2012/12/12/neutrinos-at-the-bottom-of-the-world-science-advent-11/https://galileospendulum.org/wp-content/uploads/2012/12/sensors-hires-sm.jpgIceCube sensorOne of the sensors for the IceCube experiment at the South Pole. The total experiment consists of 86 strings of 60 detectors - 5,160 detectors in all - in shafts drilled deep into the pure Antarctic ice. This provides an excellent way to detect neutrinos: when one strikes an atom, it produces a fast-moving muon, which in turn emits distinctive blue light as it travels. [Credit: Tom Gaisser]https://galileospendulum.org/wp-content/uploads/2012/12/hole-hires-sm.jpga hole in the ice for neutrino detectorsThe IceCube detector at the South Pole consists of 86 strings of 60 detectors - 5,160 detectors in all. The pure Antarctic ice provides an excellent way to detect neutrinos.2012-12-12T15:12:56+00:00monthlyhttps://galileospendulum.org/2012/12/11/footprints-on-the-moon-science-advent-10/https://galileospendulum.org/wp-content/uploads/2012/12/apollo_11.jpgApollo 11 siteThe Apollo 11 landing site, as seen from Moon orbit by the Lunar Reconnaissance Orbiter (LRO). Let what you’re seeing sink in for a moment: the image includes the base of the Lunar Module, the camera they left behind on the Moon’s surface, and the actual tracks left by Armstrong and Buzz Aldrin. [Credit: NASA/U. of Arizona]2012-12-11T15:05:56+00:00monthlyhttps://galileospendulum.org/2012/12/10/my-favorite-moon-science-advent-9/2012-12-14T20:10:46+00:00monthlyhttps://galileospendulum.org/2011/12/19/moonday-hyperion-to-a-saturn/https://galileospendulum.org/wp-content/uploads/2011/12/hyperion_movie1.gifHyperion animationAnimation of Hyperion's chaotic rotation, generated from still images. Click for more information.https://galileospendulum.org/wp-content/uploads/2011/12/hyperion_movie.gifHyperion animationAnimation of Hyperion rotation, created from a series of still photos. Click for more information.https://galileospendulum.org/wp-content/uploads/2011/12/hyperion_comparison.pngHyperion compared to Earth and MoonHyperion compared to Earth and the Moon.https://galileospendulum.org/wp-content/uploads/2011/12/hyperion.jpgSaturn's strange moon HyperionSaturn's strange moon Hyperion, one of the largest irregularly-shaped objects in the Solar System.2012-12-10T14:15:44+00:00monthlyhttps://galileospendulum.org/2012/12/09/a-phenomenal-galaxy-science-advent-8/https://galileospendulum.org/wp-content/uploads/2012/12/hercules_a_vla.jpgradio galaxy Hercules AThe radio galaxy Hercules A, seen in visible light (the galaxy at the center, background galaxies) and radio light, which shows the huge jets of matter streaming from the galaxy's central black hole. [Credit; NASA, ESA, S. Baum & C. O'Dea (RIT), R. Perley and W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)]2012-12-09T15:15:37+00:00monthlyhttps://galileospendulum.org/2012/12/08/a-very-large-telescope-science-advent-7/2012-12-08T14:09:11+00:00monthlyhttps://galileospendulum.org/2012/12/07/the-morning-star-on-the-face-of-the-sun-science-advent-6/2012-12-07T15:11:28+00:00monthlyhttps://galileospendulum.org/2012/12/06/revealing-the-smallest-particles-science-advent-5/https://galileospendulum.org/wp-content/uploads/2012/12/bubblechamber.jpgbubblechamber2012-12-06T14:26:58+00:00monthlyhttps://galileospendulum.org/2012/12/05/a-smoky-candle-science-advent-4/https://galileospendulum.org/wp-content/uploads/2012/12/candle_smoke.jpgcandle smokeSmoke from a recently extinguished candle demonstrates some beautiful physics. Near the wick, the smoke rises in an orderly way, exhibiting laminar flow. Higher up, interaction with air molecules (which move randomly) breaks the flow into delicate turbulence. [Credit: Jan Gottweiß]2012-12-05T19:39:14+00:00monthlyhttps://galileospendulum.org/2012/12/04/chaos-science-advent-3/https://galileospendulum.org/wp-content/uploads/2012/12/chaotic_oscillator.pnga chaotic oscillatorA "strange attractor" produced by a pendulum subjected both to a driving force and a brake. The balance between these opposing forces produces an obvious pattern that never repeats itself.2012-12-04T14:57:16+00:00monthlyhttps://galileospendulum.org/2012/12/03/an-egg-moon-science-advent-2/https://galileospendulum.org/wp-content/uploads/2012/12/methone_cassini_765.jpgMethoneSaturn's egg-shaped moon, Methone. [Credit: Cassini Imaging Team/ISS/JPL/ESA/NASA]2012-12-03T15:02:27+00:00monthlyhttps://galileospendulum.org/2012/12/02/spiral-galaxy-m81-science-advent-1/https://galileospendulum.org/wp-content/uploads/2012/12/messier_81_hst.jpgM81 spiral galaxyThe spiral galaxy M81, as seen by the Hubble Space Telescope. Galaxies such as this contain roughly 10 times as much dark matter as ordinary matter. [Credit: NASA/ESA/Hubble Heritage Team (STScI/AURA)]2012-12-03T20:08:23+00:00monthlyhttps://galileospendulum.org/2012/11/29/proposed-warp-drive-is-still-science-fiction/https://galileospendulum.org/wp-content/uploads/2012/11/vector_trajectory.pngspacetime trajectoryA vector tells us the direction of motion along a trajectory - a path in spacetime. The length and orientation of the vector reveals a lot about the geometry of spacetime, dictated by G in Einstein's equations.https://galileospendulum.org/wp-content/uploads/2012/11/einstein_eqn.pngEinstein_eqn2012-11-29T16:25:53+00:00monthlyhttps://galileospendulum.org/2012/11/21/grandeur/https://galileospendulum.org/wp-content/uploads/2012/11/ngc6357a_small.jpgNGC 6357The nebula NGC 6357, containing some of the most massive stars known. These stars produce such energetic light as to erode a cavity into the cocoon of gas they inhabit, leaving the cathedral in the image. [Credit: NASA, ESA and J. M. Apellániz (IAA, Spain)]2012-11-21T16:58:03+00:00monthlyhttps://galileospendulum.org/2012/11/20/open-letter-to-senator-marco-rubio/https://galileospendulum.org/wp-content/uploads/2012/11/signature.pngsignature2012-11-26T01:21:41+00:00monthlyhttps://galileospendulum.org/2012/11/15/children-are-not-natural-scientists/2013-09-02T18:06:40+00:00monthlyhttps://galileospendulum.org/2012/11/11/3645/2012-11-11T22:20:52+00:00monthlyhttps://galileospendulum.org/2012/11/09/carl-sagan-day-let-there-be-100-sagans/2013-07-26T17:05:03+00:00monthlyhttps://galileospendulum.org/2012/11/08/black-holes-in-the-library/2012-11-08T22:28:59+00:00monthlyhttps://galileospendulum.org/2012/11/01/turning-back-looking-back/https://galileospendulum.org/wp-content/uploads/2012/11/dish_crop.jpgone of the telescopes of the VLAOne of the 27 radio telescopes that comprise the Very Large Array (VLA) in New Mexico. Each telescope is 25 meters (about 82 feet) in diameter.https://galileospendulum.org/wp-content/uploads/2012/11/view_from_dome_small.jpgview from LBT domeThe view from the Large Binocular Telescope (LBT) dome on top of Mount Graham in Arizona. I had the privilege of standing on the platform inside the dome when it opened for the evening's observations.https://galileospendulum.org/wp-content/uploads/2012/11/self-portrait_crop.jpgSelf-portrait at VERITASSelf-portrait in one of the mirror segments at VERITAS (Very Energetic Radiation Imaging Telescope Array System), the gamma ray observatory in southern Arizona. The highest energy radiation creates showers of photons when it enters the atmosphere, which can be detected from the ground. [Credit: moi]2012-11-01T16:12:48+00:00monthlyhttps://galileospendulum.org/2012/10/27/from-swamp-to-desert-to-mountaintop-in-four-days/https://galileospendulum.org/wp-content/uploads/2012/10/barchan_dune_cover.jpgbarchan dune at White Sands National MonumentA barchan dune at White Sands National Monument.https://galileospendulum.org/wp-content/uploads/2012/10/guadalupe_mountains_small.jpgthe edge of the Guadalupe MountainsA peak at the edge of the Guadalupe Mountains in western Texas, near the New Mexico border. I had to restrain myself from stopping every few miles to take photos, it was just that beautiful. (It was also rather desolate: the longest drive I've ever taken that passed through no towns, and for much of it, no habitations either.)https://galileospendulum.org/wp-content/uploads/2012/10/barrilla_mountains_texas_small.jpgBarrilla Mountains in TexasVolcanic rock formation in the Barrilla Mountains in western Texas. Despite what people told me, I didn't find driving through Texas boring at all.2012-10-27T15:27:47+00:00monthlyhttps://galileospendulum.org/2012/10/22/the-bowler-hat-goes-south/https://galileospendulum.org/wp-content/uploads/2012/10/alligator_zoom.jpgan alligator in MississippiAn alligator near Davis Bayou in Mississippi. It was far enough away from me that I had to use my camera's maximum zoom, and even then I wasn't able to confirm it actually was an alligator until I loaded the photo onto my computer.https://galileospendulum.org/wp-content/uploads/2012/10/cowpens_meadow_small.jpgsite of the Battle of CowpensA portion of the battlefield at Cowpens in South Carolina. On January 17 in 1781, rebel soldiers under the command of Luke Skywalker Daniel Morgan defeated a detachment of British soldiers and Loyalists (colonials loyal to the Crown).2012-10-27T14:07:34+00:00monthlyhttps://galileospendulum.org/2012/10/20/on-the-road-again/https://galileospendulum.org/wp-content/uploads/2012/10/castle_rock_wisconsin_snap.jpgCastle Rock in WisconsinCastle Rock, once an island in a huge glacial lake in Wisconsin, now an impressive formation in the middle of a plain. I took this photo during the first leg of my road trip researching my book.2012-10-22T23:51:00+00:00monthlyhttps://galileospendulum.org/2012/10/16/the-dream-of-other-earths/https://galileospendulum.org/wp-content/uploads/2012/10/alphacentauri.jpgAlpha CentauriAlpha Centauri family portrait: B (left) and A (right).https://galileospendulum.org/wp-content/uploads/2012/10/alpha_centauri_b_still.jpgArtist's impression of Alpha Centauri BbArtist's impression of Alpha Cen Bb, a newly discovered Earth-mass planet orbiting Alpha Centauri B. [Credit: ESO/L. Calçada]2012-10-17T00:09:38+00:00monthlyhttps://galileospendulum.org/2012/10/16/ada-lovelace-day-my-friends-and-colleagues/2012-10-16T21:18:11+00:00monthlyhttps://galileospendulum.org/2012/10/14/where-is-space/2012-10-14T20:43:59+00:00monthlyhttps://galileospendulum.org/2012/10/10/the-nobel-savages/https://galileospendulum.org/wp-content/uploads/2012/10/ed_yong_modest_proposal.pngI hereby resubmit my suggestion that Nobel winners should get half the money now, & the rest if they don't utterly lose it in 10 yrsEd Yong's modest proposalhttps://galileospendulum.org/wp-content/uploads/2012/10/sam_elliott_nobel_laureate.jpgDavid Wineland totally looks like Sam Elliott.David Wineland totally looks like Sam Elliott.2012-10-11T16:22:56+00:00monthlyhttps://galileospendulum.org/2012/10/09/the-2012-nobel-prize-in-physics-trapping-and-measuring-particle-states/https://galileospendulum.org/wp-content/uploads/2012/10/photon_trap.pngphoton trapTrapping photons requires creating a cavity bounded by mirrors. Measurement is performed using Rydberg atoms - atoms in a maximally excited state, so that the electrons are barely connected to the nuclei. [Credit: Johan Jarnestad/Royal Swedish Academy of Sciences]https://galileospendulum.org/wp-content/uploads/2012/10/ion_trap.pngIon trapSchematic of an ion trap, using electromagnetic fields and light to confine, control, and measure the quantum state of beryllium ions. [Credt: Johan Jarnestad/Royal Swedish Academy of Sciences]2012-11-15T14:53:43+00:00monthlyhttps://galileospendulum.org/2012/09/29/seeing-believing-and-science/https://galileospendulum.org/wp-content/uploads/2012/09/congealed_horseradish_salad.pngweird recipeI'm including this recipe, not because it actually has to do with the blog post, but because it's another example of life in the Bible Belt.2012-11-15T14:37:54+00:00monthlyhttps://galileospendulum.org/2012/09/26/words-are-flowing-out-like-endless-rain-into-a-paper-cup/https://galileospendulum.org/wp-content/uploads/2012/09/xdf_medium.jpgHubble eXtreme Deep Field surveyYo momma's so ugly, the Universe is expanding so galaxies can get away from her.2012-09-26T20:09:11+00:00monthlyhttps://galileospendulum.org/2012/09/17/ships-on-a-quantum-sea/https://galileospendulum.org/wp-content/uploads/2012/09/electron_electron.pngFeynman diagramsFeynman diagrams of the same interactions in the previous figure. They are simpler, but they convey the same information.https://galileospendulum.org/wp-content/uploads/2012/09/tree_level.pngLike charges repel, opposites attract - quantum styleLike charges repel, opposites attract: quantum style. On the simplest level, repulsion between two electrons can be seen as the exchange of photons, which knock the particles off course. Attraction can be described if one of the particles moves backward in time, emitting photons that also move backward in time.2012-11-09T14:14:08+00:00monthlyhttps://galileospendulum.org/2012/09/16/two-years-of-galileos-pendulum/2012-09-16T20:10:35+00:00monthlyhttps://galileospendulum.org/2012/09/11/your-usual-seminar-speakers-are-bad-and-you-should-feel-bad/2012-09-11T20:11:33+00:00monthlyhttps://galileospendulum.org/2012/09/08/it-only-takes-a-moment/https://galileospendulum.org/wp-content/uploads/2012/09/curiosity_self-portrait_walle.jpgPut on your Sunday clothes - there's lots of world out there!Mars Curiosity has an inspiring message for you. [Credit: NASA/JPL/MSSS/Emily Lakdawalla]2012-09-12T14:06:07+00:00monthlyhttps://galileospendulum.org/2012/09/07/beauty-from-technology/https://galileospendulum.org/wp-content/uploads/2012/09/jupiter_vgr1_small.pngVoyager 1 mosaic of JupiterJupiter is a fascinating planet, but it's unlikely to bring you gifts, whatever astrologers might tell you. This mosaic of Jupiter was created from images taken by Voyager 1. Click on the image to see a much larger version, and to read the entire story of how Björn Jónsson made the mosaic - it's fascinating to know how it was done, even though the image can be appreciated on its own. [Credit: NASA/JPL/Björn Jónsson]2012-09-11T04:04:46+00:00monthlyhttps://galileospendulum.org/2012/09/05/so-this-physicist-walked-into-a-bar/https://galileospendulum.org/wp-content/uploads/2012/09/3c75blackholes_cxc_f.jpgtwo black holes in the galaxy 3C75Two black holes in the galaxy 3C75, which formed from the merger of two smaller galaxies. It's possible in the future that the two black holes will collide and merge into a bigger black hole.https://galileospendulum.org/wp-content/uploads/2012/09/black_hole_ejection.jpegapparent ejection of a black holeThe apparent ejection of a black hole from its host galaxy. Sleep well, children! [Credit: Chandra X-ray observatory/NASA]https://galileospendulum.org/wp-content/uploads/2012/09/fermi_galactic_bubbles_slide.jpgBubbles at the center of the Milky WayNew evidence supports the idea that the bubbles emanating from the center of the Milky Way were probably made by star formation. Much ealier speculation credited the black hole in the galaxy's nucleus, an idea I promoted. [Credit: Fermi gamma ray observatory/NASA]https://galileospendulum.org/wp-content/uploads/2012/09/m87_jet_combined.jpgjet from M87The large image shows the jet streaming from the center of the galaxy M87, in visible light. The inset zooms in on the black hole, and shows the swirling gas around the galaxy's core in radio light. M87 is one of the largest galaxies known, and has the largest-known black hole, estimated around 6.6 billion times the mass of the Sun. [Credit: J. A. Biretta et al./Hubble Heritage Team (STScI /AURA)/NASA, NRAO/AUI/NSF/W. Cotton (inset)]https://galileospendulum.org/wp-content/uploads/2012/09/cena_chandra_big.gifCentaurus AThe active galaxy Centaurus A, rendered in several different types of light. Note in radio waves (the lower two images), the galaxy itself seems to disappear, replaced by crossing jets of radio-emitting jets. Those are produced by the supermassive black hole at the galaxy's core.https://galileospendulum.org/wp-content/uploads/2012/09/cygnus_x1_small.jpgcygnus_x1_smallhttps://galileospendulum.org/wp-content/uploads/2012/09/cygus_x1_small1.jpgCygnus X-1The first black hole ever discovered: Cygnus X-1. We're seeing X-ray emission from plasma stripped from a companion star as it falls onto the black hole. [Credit: Chandra X-ray observatory/NASA]https://galileospendulum.org/wp-content/uploads/2012/09/cygus_x1_small.jpgCygnus X1The X-ray source known as Cygnus X-1 was the first black hole identified. Charged particles (electrons and protons) stripped off a companion star are accelerated nearly to the speed of light, causing them to emit a lot of high-energy photons. [Credit: Chandra X-ray observatory/NASA]https://galileospendulum.org/wp-content/uploads/2012/09/central-black-hole.gifcentral black holeThe motion of stars ("stellar objects" or "SO") near the center of the Milky Way. While the object marked with a star is invisible in infrared light, the orbits of the stars reveal its mass to be 4 million times that of the Sun, but it takes up less space than the Solar System. The only object fitting the bill is a supermassive black hole. [Credit: Keck/UCLA]https://galileospendulum.org/wp-content/uploads/2012/09/sagittarius_astar_slide.jpgGalactic center in X-raysThe center of our galaxy in X-ray light. [Image courtesy of the Chandra X-ray observatory and NASA.]2012-09-29T23:49:40+00:00monthlyhttps://galileospendulum.org/2012/09/02/the-ghost-of-talks-past-the-ghost-of-talks-yet-to-come/https://galileospendulum.org/wp-content/uploads/2012/08/fermi_galactic_bubbles_zoom.jpgBubbles at the center of the Milky WayThe orbiting Fermi gamma ray observatory found two huge bubbles of gamma ray-emitting gas emanating from the black hole at the center of the Milky Way. My upcoming talk will have the scoop.2012-08-31T22:02:26+00:00monthlyhttps://galileospendulum.org/2012/08/31/carnival-of-cosmology-2-observational-challenges/https://galileospendulum.org/wp-content/uploads/2012/08/cmb_timeline.jpgTimeline of the UniverseTimeline of the Universe, from the Big Bang to today. (Courtesy of NASA/WMAP Science Team)2012-08-31T19:49:32+00:00monthlyhttps://galileospendulum.org/2012/08/31/the-glory-and-despair-of-cosmology/2012-09-01T17:14:37+00:00monthlyhttps://galileospendulum.org/2012/08/25/rest-in-peace-neil-armstrong/https://galileospendulum.org/wp-content/uploads/2012/08/armstrong_on_moon.jpgNeil Armstrong on the MoonThe only clear photo of Neil Armstrong on the surface of the Moon. (Photo courtesy of NASA)2012-08-25T20:55:52+00:00monthlyhttps://galileospendulum.org/2012/03/08/if-you-love-a-flower-found-on-a-star/https://galileospendulum.org/wp-content/uploads/2012/03/schwarzschild1.pngschwarzschildhttps://galileospendulum.org/wp-content/uploads/2012/03/schwarzschild.pngschwarzschildhttps://galileospendulum.org/wp-content/uploads/2012/03/surface_gravity1.pngmass and radius of objects with the same surface gravity as EarthA plot of mass (vertical axis) against radius (horizontal axis), keeping surface gravity the same. Each one of these points changes the radius by a factor of 10, which to keep surface gravity the same means changing the mass by a factor of 100. All these numbers are written as a fraction of Earth's values. I've used something known as a logarithmic scale, which allows us to look at numbers of very different sizes easily.https://galileospendulum.org/wp-content/uploads/2012/03/surface_gravity.pnga plot of mass and radius, keeping surface gravity the sameA plot of mass (vertical axis) against radius (horizontal axis), keeping surface gravity the same. Each one of these points changes the radius by a factor of 10, which to keep surface gravity the same means changing the mass by a factor of 100. All these numbers are written as a fraction of Earth's values. I've used something known as a logarithmic scale, which allows us to look at numbers of very different sizes easily.https://galileospendulum.org/wp-content/uploads/2012/03/gravity_size.pngrelationship of gravity to sizeThe relationship of gravity to size: if two objects have the same mass, but one is smaller than the other, the smaller object will have correspondingly higher surface gravity. https://galileospendulum.org/wp-content/uploads/2012/03/le_petit_prince.pngLe Petit Prince"Le Petit Prince" by Antoine de Saint-Exupery. I picked up this copy in my Richmond neighborhood's second-hand bookshop for $3. Now let's see how much high school French I remember....2013-05-24T10:15:35+00:00monthlyhttps://galileospendulum.org/2012/08/22/the-terrible-horrible-no-good-very-bad-scientific-talk/2012-08-24T17:47:12+00:00monthlyhttps://galileospendulum.org/2012/08/20/voyager-at-35/2012-08-20T21:58:56+00:00monthlyhttps://galileospendulum.org/2012/08/20/calling-for-cosmology-posts/2012-08-20T19:27:14+00:00monthlyhttps://galileospendulum.org/2012/08/15/how-i-was-rhic-rolled/https://galileospendulum.org/wp-content/uploads/2012/08/quark_matter.jpgname tag from Quark Matter 2012 conferenceMy name tag from the Quark Matter 2012 conference, along with a few references. (Not shown: my cat Harriet, who resented the fact that I was taking pictures instead of feeding her.)2012-08-15T21:08:28+00:00monthlyhttps://galileospendulum.org/2012/08/13/greetings-from-quark-matter-2012/2012-08-13T12:37:39+00:00monthlyhttps://galileospendulum.org/2012/08/12/murder-by-physics/https://galileospendulum.org/wp-content/uploads/2012/08/short_chain.pngshorter chain means less speedA shorter chain means less speed at the bottom of the swing.https://galileospendulum.org/wp-content/uploads/2012/08/long_chain.pngthe murder weapon in Busman's HoneymoonThe murder weapon in Busman's Honeymoon. Using a weighted cactus pot as a pendulum, the murderer set a booby trap. The speed the pot has at the bottom of its swing is the same as the speed it would have if it were dropped vertically from the same height.2012-08-12T23:19:31+00:00monthlyhttps://galileospendulum.org/2012/08/09/fear-of-a-black-hole/2012-08-09T18:25:19+00:00monthlyhttps://galileospendulum.org/2012/08/06/mars-curiosity-the-builders-win/https://galileospendulum.org/wp-content/uploads/2012/08/first_4_msl_images.jpgfirst 4 images from MSLThe first four images from MSL (Mars Science Laboratory), AKA Curiosity. The top two images are from the front hazard camera (hazcam) and show the shadow of the rover on Mars' surface. The bottom two images are with the rear hazcam, and you can see one of the rover's wheels clearly. (Via Emily Lakdawalla/Planetary Society)2012-08-06T12:50:07+00:00monthlyhttps://galileospendulum.org/2012/08/03/copernicus-and-the-allure-of-the-anthropic-principle/2012-08-20T23:15:08+00:00monthlyhttps://galileospendulum.org/2012/08/02/bone-idle/https://galileospendulum.org/wp-content/uploads/2012/08/onslow_small.jpgself-portrait as OnslowSelf-portrait as Onslow, reading one of his favorite books.2012-08-02T14:58:34+00:00monthlyhttps://galileospendulum.org/2012/07/26/big-questions-about-dark-energy/https://galileospendulum.org/wp-content/uploads/2012/07/decam_rig_snap.jpgTest rig for the Dark Energy CameraIt's not Stargate - it's the test rig at Fermilab for the Dark Energy Camera. This instrument is a huge digital camera now mounted on the 4-meter telescope at Cerro Tololo - the same telescope where dark energy was discovered.https://galileospendulum.org/wp-content/uploads/2012/07/equation_of_state.pngequation_of_state2012-08-02T13:10:57+00:00monthlyhttps://galileospendulum.org/2012/07/30/the-carnival-of-cosmology-bloggers-on-dark-energy/https://galileospendulum.org/wp-content/uploads/2012/07/sn1994d.jpgSN1994DSupernova SN1994d, the type of supernova first used to measure the acceleration of the Universe. (Credit: NASA/ESA/Hubble Key Project/High-Z Supernova Search)2012-08-08T12:16:03+00:00monthlyhttps://galileospendulum.org/2012/07/17/carnival-of-cosmology-dark-energy/https://galileospendulum.org/wp-content/uploads/2012/07/preposterous.pngpreposterous universe2012-07-30T15:13:40+00:00monthlyhttps://galileospendulum.org/2012/07/28/emergent-beauty/https://galileospendulum.org/wp-content/uploads/2012/07/saturn-and-earth.jpgSaturn and EarthEarth as seen through the rings of Saturn.https://galileospendulum.org/wp-content/uploads/2012/07/saturn-eclipse.jpgSaturn eclipseSaturn, eclipsing the Sun. For a much higher-resolution version, click on the image. [Credit: NASA/JPL/Space Science Institute]2012-08-03T16:10:39+00:00monthlyhttps://galileospendulum.org/2012/07/27/small-change-of-plans/2012-07-27T13:51:00+00:00monthlyhttps://galileospendulum.org/2011/10/04/2011-nobel-prize-in-physics-discovery-of-dark-energy/https://galileospendulum.org/wp-content/uploads/2011/10/dark_energy_pressure.pngWhy dark energy is weirdWhy dark energy is weird. The top two pictures shows how normal gases behave: in a small volume, the gas is compressed and can support a large weight, while if the gas expands, its pressure decreases. The bottom two pictures show what happens if you could somehow confine dark energy: the smaller the volume, the smaller the pressure, while a large volume has a larger pressure.https://galileospendulum.org/wp-content/uploads/2011/10/las_campanas.jpgLas CampanasThe telescopes at Las Campanas in Chile, where the acceleration of the universe was observed.2013-09-04T16:04:16+00:00monthlyhttps://galileospendulum.org/2012/07/25/pages-to-go-before-i-sleep/2012-07-26T00:24:48+00:00monthlyhttps://galileospendulum.org/2012/07/20/in-search-of-grote-reber/https://galileospendulum.org/wp-content/uploads/2012/07/grote_reber_marker_small.jpgHistorical markerThe historical marker for Grote Reber's telescope, corresponding roughly to where it stood. The telescope is now in West Virginia, the house was moved to another neighborhood, and the street itself doesn't exist under the same name.https://galileospendulum.org/wp-content/uploads/2012/07/grote1.gifGrote Reber2012-07-21T15:53:11+00:00monthlyhttps://galileospendulum.org/2012/07/16/moonday-haumea-help-you/https://galileospendulum.org/wp-content/uploads/2012/07/pluto_5_moons.jpgPluto's 5 moons, with orbitsPluto's five moons, with their orbits drawn in. Note how regular they are, lying in the same plane. (Courtesy of Astronomy Picture of the Day)2012-07-17T17:58:24+00:00monthlyhttps://galileospendulum.org/2012/07/13/ive-been-nixed/https://galileospendulum.org/wp-content/uploads/2012/07/me_as_nix_thumbnail.jpgI've been NixedClick to read the whole comic. It is most droll.2012-07-13T18:23:25+00:00monthlyhttps://galileospendulum.org/2012/07/12/busy-little-iceball/https://galileospendulum.org/wp-content/uploads/2012/07/pluto_moon_p5_2012.jpgPluto and its five moonsPluto and its five moons: Charon, Nix, Hydra, P4, and newly discovered P5. The image is from the Hubble Space Telescope, with a mask over the central part of the image to keep bright Pluto from washing out the tinier moons. Credit: NASA; ESA; M. Showalter, SETI Institute2012-07-13T00:03:00+00:00monthlyhttps://galileospendulum.org/2012/07/09/the-soft-sultry-sound-of-my-voice/https://galileospendulum.org/wp-content/uploads/2012/07/good-night-and-good-luck-2.jpg"Good Night and Good Luck"2012-07-09T13:57:04+00:00monthlyhttps://galileospendulum.org/2012/07/05/breaking-observation-of-dark-matter-bridge-between-galaxy-clusters/https://galileospendulum.org/wp-content/uploads/2012/07/a222-223.jpgMap of mass distribution in Abell 222/223Composite image of the galaxy clusters Abell 222 and 223, along with the mass distribution, shown in blue and the yellow contours. The clusters themselves are high concentrations of mass, but there's an additional structure that contributes almost no light: a filament of dark matter connecting the two clusters. This kind of filament is predicted by the theory of large-scale structure. (Image by Jörg Dietrich, University of Michigan/University Observatory Munich.)2012-07-05T19:17:41+00:00monthlyhttps://galileospendulum.org/2012/06/29/galileo-was-a-kickin-lute-player/https://galileospendulum.org/wp-content/uploads/2012/06/me_and_clay.jpgjammingYour blogger (left) playing harmonica in a band consisting of professors and teachers.2012-07-11T20:03:16+00:00monthlyhttps://galileospendulum.org/2011/02/19/music-science-sexy/2012-06-29T13:12:33+00:00monthlyhttps://galileospendulum.org/2012/06/21/the-tyranny-of-novelty/2012-06-21T16:12:36+00:00monthlyhttps://galileospendulum.org/2012/06/19/happy-birthday-blaise-pascal/2012-06-19T18:35:31+00:00monthlyhttps://galileospendulum.org/2012/06/17/beauty-in-simplicity/https://galileospendulum.org/wp-content/uploads/2012/06/jupiter_rings.jpgJupiter's rings, as seen by Voyager 1.Jupiter's rings, as seen by Voyager 1.2012-06-17T20:46:44+00:00monthlyhttps://galileospendulum.org/2012/06/14/vote-2012/https://galileospendulum.org/wp-content/uploads/2012/06/pogo-giantpin.jpgPogo possum campaign button2012-06-14T13:25:46+00:00monthlyhttps://galileospendulum.org/2012/06/11/moonday-double-world/https://galileospendulum.org/wp-content/uploads/2012/06/plutos_moons.jpgPluto's four moonsPluto's four moons, imaged last year. Click on the image for more information about the discovery of P4.https://galileospendulum.org/wp-content/uploads/2012/06/charon_comparison.pngPluto and Charon compared to Earth and MoonPluto and Charon are small compared to Earth and the Moon, but Charon is downright huge compared to its host world. We don't have any clear images of either Pluto or Charon, so I used a 1994 Hubble Space Telescope image that includes both bodies.2012-06-11T16:12:44+00:00monthlyhttps://galileospendulum.org/2011/07/20/thats-not-a-moon-its-a-wait-it-is-a-moon-after-all/2012-06-11T15:31:09+00:00monthlyhttps://galileospendulum.org/2012/06/09/imaginary-numbers-are-real/https://galileospendulum.org/wp-content/uploads/2012/06/two_slit_phases.pngrelative phase between two pathsThe relative phase between two paths is measurable, and exhibits itself in the form of interference. The red and blue lines represent possible paths a single photon can take when it goes through a barrier with two openings. If the phases agree along two different paths, then the photon is likely to land at that spot. If the two phases are opposite, then the photon won't land at that spot at all.https://galileospendulum.org/wp-content/uploads/2012/06/probability.pngprobabilityhttps://galileospendulum.org/wp-content/uploads/2012/06/phase.pngwavefunctionHow to interpret the magnitude and phase of the wavefunction using the complex plane.https://galileospendulum.org/wp-content/uploads/2012/06/wavefunction.pngwavefunctionhttps://galileospendulum.org/wp-content/uploads/2012/06/complex_conjugate.pngFun fact: if you say this every time a professor does something to a complex-number equation that drops the imaginary part, they'll eventually move the class to another room and tell everyone else except you.Mathematical wisdom from xkcd.2012-06-11T12:06:57+00:00monthlyhttps://galileospendulum.org/2012/06/05/congratulations-youre-dumb/https://galileospendulum.org/wp-content/uploads/2012/06/venus_2004.jpgVenus transit, from 2004Several of us got up very early to view the 2004 Venus transit through the Rutgers University 21-inch telescope. Ted Williams, professor of astronomy at Rutgers, took this picture during that session; the black circle on the Sun's disc is Venus, a planet nearly the size of Earth.https://galileospendulum.org/wp-content/uploads/2012/06/orbit_inclination.pngWhy Venus transits are rareWhy Venus transits are rare: they can only occur when both Venus and Earth are in the "transit zones" shown here. In fact, I've exaggerated the size both of the zones and of the Sun, so the events are even more rare than the image suggests.2012-06-05T19:40:59+00:00monthlyhttps://galileospendulum.org/2012/06/01/back-roads-dark-skies-update/https://galileospendulum.org/wp-content/uploads/2012/06/yerkes_lifting_mechanism_bw.jpglifting assembly at YerkesOne of the lifts at Yerkes Observatory in Wisconsin, which raises and lowers the entire floor of the observatory. I made the image look like an old photo because it felt appropriate for the space.2012-06-04T15:09:35+00:00monthlyhttps://galileospendulum.org/2012/05/26/my-suitcase-and-tuba-in-hand/https://galileospendulum.org/wp-content/uploads/2012/05/minos_snap.jpgMINOS experimentThe Main Injector Neutrino Oscillation Search (MINOS) detector in Soudan. Behind this octagonal steel plate lies a series of plastic sheets. Note the scale of the experiment from the stairs at the right.2012-05-26T16:08:33+00:00monthlyhttps://galileospendulum.org/2012/05/21/the-blog-from-the-north-country/https://galileospendulum.org/wp-content/uploads/2012/05/headframe_snap_bw.jpgheadframe of Soudan Iron MineThe headframe of the Soudan Iron Mine, which still operates the lift cage descending a half-mile below ground. The CDMS experiment is located at the bottom of this mine. I made this photograph look old because I felt like it.2012-05-22T20:03:46+00:00monthlyhttps://galileospendulum.org/2012/05/19/fermilab-teaser/https://galileospendulum.org/wp-content/uploads/2012/05/cdf_pipe_highlight.jpgpipe for particle trajectoryThe pipe through which protons and antiprotons travel through CDF.https://galileospendulum.org/wp-content/uploads/2012/05/cdf_partly_open_snap.jpga peek inside CDFA peek inside CDF, which has been partly opened. The scale is hard to grasp here, but the ladder at the lower right corner might help. Much of what you can see is detector arrays of various sorts, along with the electronics that manage them. [Credit: moi]2012-05-19T13:44:16+00:00monthlyhttps://galileospendulum.org/2012/05/17/greetings-from-illinois-also-the-real-conference-wrap-up/2012-05-18T02:54:30+00:00monthlyhttps://galileospendulum.org/2012/05/16/back-roads-dark-skies-a-cosmological-journey/https://galileospendulum.org/wp-content/uploads/2012/05/fermilab_or_bust.jpgFermilab or bust2012-05-15T22:16:39+00:00monthlyhttps://galileospendulum.org/2012/05/15/conference-wrap-up-waiting-for-godot-particles/https://galileospendulum.org/wp-content/uploads/2012/05/wondermark-toothpaste_panel.gifpanel from "Wondermark"Panel from "Wondermark" by David Malki!, illustrating (kind of) how new particles are created in high-energy collisions.2012-05-15T19:23:45+00:00monthlyhttps://galileospendulum.org/2012/05/12/the-flavor-of-neutrinos/https://galileospendulum.org/wp-content/uploads/2012/05/neutrino_scattering.pngNeutrino scattering Feynman diagramsNeutrino scattering Feynman diagrams. In the first case, any neutrino will do: it simply "bounces off" another particle. It exchanges a neutral Z boson in the process, so this is known as a "neutral current" interaction. Electron neutrinos can also interact via the W bosons, either by swapping themselves with an electron, or by changing a neutron into a proton. These are the charged current interactions.https://galileospendulum.org/wp-content/uploads/2012/05/neutrino_sphere1.pngneutrino flavor as a position on a sphereEach neutrino flavor is a different set of "coordinates", combinations of the three mass states (labeled 1, 2, and 3). The specific position is determined by the "mixing angle", which currently must be determined through experiment. (I made some up, so my picture should not be considered accurate.)https://galileospendulum.org/wp-content/uploads/2012/05/kamiokande.jpgtechnicians examine the detectors at KamiokandeTechnicians in a boat examine the detectors at the Kamiokande neutrino observatory in Japan. [Credit: Kamioka Observatory, ICRR (Institute for Cosmic Ray Research), The University of Tokyo]https://galileospendulum.org/wp-content/uploads/2012/05/neutrino_sphere.pngneutrino flavor as coordinates on a sphere2013-01-09T16:43:21+00:00monthlyhttps://galileospendulum.org/2012/05/09/why-do-conference-talks-suck-and-how-can-we-change-that/2012-05-14T17:22:43+00:00monthlyhttps://galileospendulum.org/2012/05/07/greetings-from-pittsburgh/2012-05-07T17:45:00+00:00monthlyhttps://galileospendulum.org/2012/05/05/blue-highways/2012-05-05T17:40:58+00:00monthlyhttps://galileospendulum.org/2012/04/27/who-are-my-readers-also-an-announcement/https://galileospendulum.org/wp-content/uploads/2012/04/flushedaway_1.jpgFlushed AwayRoddy St. James of Kensington talks to himself. Am I just Roddy?2012-05-05T14:53:23+00:00monthlyhttps://galileospendulum.org/2012/05/03/how-i-feel/https://galileospendulum.org/wp-content/uploads/2012/05/leopard_lol.jpgsnow leopard2012-05-25T08:17:54+00:00monthlyhttps://galileospendulum.org/2012/05/02/is-cosmology-in-shambles/https://galileospendulum.org/wp-content/uploads/2012/05/dmsandwich.gifdark matter sandwichhttps://galileospendulum.org/wp-content/uploads/2012/05/galactic_structure2.pngcartoon of structure of a spiral galaxyA highly elegant cartoon of the structure of a spiral galaxy. The dark matter halo is the black circle (generally considered to be spherical), which is much larger than what we usually think of as the "galaxy" - the luminous portion containing the highest concentration of stars.2012-06-13T00:37:27+00:00monthlyhttps://galileospendulum.org/2012/04/30/moonday-saturn-snags-snowball-satellite/https://galileospendulum.org/wp-content/uploads/2012/04/aspherical_phoebe.jpgMap of how Phoebe deviates from being a sphereMap of how Phoebe deviates from being a sphere, from the Cassini imaging project CICLOPS. Even though it's not spherical, it's close enough that it probably used to be a sphere before it was battered by impacts.https://galileospendulum.org/wp-content/uploads/2012/04/phoebe_comparison.pngPhoebe compared to Earth and the MoonPhoebe's size compared to Earth and the Moon.https://galileospendulum.org/wp-content/uploads/2012/04/phoebe_closeup.jpgSaturn's moon PhoebeSaturn's moon Phoebe, as seen by the Cassini space probe.2012-04-30T20:50:35+00:00monthlyhttps://galileospendulum.org/2012/04/28/stunning-saturn-sadistic-sippy-cups-magnetic-pigeons-and-more/2012-04-28T13:18:17+00:00monthlyhttps://galileospendulum.org/2012/04/26/everything-is-geometrical-hermann-grassmanns-algebra/https://galileospendulum.org/wp-content/uploads/2012/04/kinematics2d.pngstroboscopic view of a thrown ballStroboscopic view of a thrown ball. The horizontal and vertical axes really do represent perpendicular directions.https://galileospendulum.org/wp-content/uploads/2012/04/scalar_grassmann.pngscalar_Grassmannhttps://galileospendulum.org/wp-content/uploads/2012/04/scalar_multiplication.pngscalar_multiplicationhttps://galileospendulum.org/wp-content/uploads/2012/04/general_grassmann.pnggeneral_grassmannhttps://galileospendulum.org/wp-content/uploads/2012/04/four_fermion_pauli.pngfour_fermion_Paulihttps://galileospendulum.org/wp-content/uploads/2012/04/four_fermions1.pngfour_fermionshttps://galileospendulum.org/wp-content/uploads/2012/04/three_fermions.pngthree_fermionshttps://galileospendulum.org/wp-content/uploads/2012/04/grassmann_product.pngGrassmann_producthttps://galileospendulum.org/wp-content/uploads/2012/04/whatparticle_small.pngWhat particle are you?What particle are you? Sean Carroll made the definitive flowchart for the Standard Model of particles and interactions; click for a much higher-resolution version.https://galileospendulum.org/wp-content/uploads/2012/04/grassmann.jpegHermann GrassmannHermann Grassmann (1809-1877), Prussian mathematician from Stettin, in what is now Poland. Hipster gentlemen, take note of his luxuriously curly chinbeard.2012-04-26T19:51:28+00:00monthlyhttps://galileospendulum.org/2012/04/23/moonday-map-the-moon-from-your-own-home/2012-04-23T14:31:58+00:00monthlyhttps://galileospendulum.org/2012/04/21/cant-keep-up-with-myself/2012-04-21T00:32:14+00:00monthlyhttps://galileospendulum.org/2012/04/20/claude-monet-and-the-subjectivity-of-color/https://galileospendulum.org/wp-content/uploads/2012/04/star_blackbody_curves.pngAmount of light produced by starsThe amount (intensity) of light produced by stars with four different surface temperatures. Note that while the blue star peaks in the UV range, it still produces a lot of visible light. The white, yellow, and red stars produce more visible light than any other kind (though the red star is creeping into the infrared).https://galileospendulum.org/wp-content/uploads/2012/04/monet_both_eyes.jpgsame scene painted using left and right eyesMonet's paintings of the same scene, using his cataract-afflicted left eye (left) and his right eye with the lens removed (right).2012-04-21T04:24:31+00:00monthlyhttps://galileospendulum.org/2012/04/17/are-astronomical-images-all-faked/2012-04-18T13:21:37+00:00monthlyhttps://galileospendulum.org/2012/04/13/two-particles-enter-no-particles-leave/https://galileospendulum.org/wp-content/uploads/2012/04/current_equivalence.pngequivalence in current representationsNegative charges moving to the right and (equal) positive charges moving to the left both represent a current flowing to the left.2012-04-26T18:49:55+00:00monthlyhttps://galileospendulum.org/2012/04/12/yuris-night/2012-04-12T16:27:22+00:00monthlyhttps://galileospendulum.org/2012/04/10/working-for-free-and-other-hazards/https://galileospendulum.org/wp-content/uploads/2012/04/exposure_doonesbury_panel.gifPanel from DoonesburyA "Doonesbury" comic that hits close to home. Click for the whole thing.2012-04-10T12:43:37+00:00monthlyhttps://galileospendulum.org/2012/04/09/moonday-earths-extra-occasional-moons/2012-04-09T20:42:35+00:00monthlyhttps://galileospendulum.org/2012/04/06/postscript-more-thoughts-on-imposter-syndrome/2012-04-06T21:25:48+00:00monthlyhttps://galileospendulum.org/2012/04/05/outsiders-imposters-and-aquatic-dinosaurs/2012-08-08T06:17:57+00:00monthlyhttps://galileospendulum.org/2011/04/16/please-dont-be-a-crackpot/2012-04-04T18:50:38+00:00monthlyhttps://galileospendulum.org/2011/05/02/cranks-crackpots-and-aquatic-apes/https://galileospendulum.org/wp-content/uploads/2011/04/crazy_cat.jpgCrazy cat2012-04-04T18:50:27+00:00monthlyhttps://galileospendulum.org/2011/05/14/crackpots-and-creationists/https://galileospendulum.org/wp-content/uploads/2011/05/god-said-it.jpgGod-Said-It2012-04-04T18:50:16+00:00monthlyhttps://galileospendulum.org/2011/10/19/citizen-science-as-a-cure-for-scientific-isolation/https://galileospendulum.org/wp-content/uploads/2011/10/young_frankenstein.jpgFrame from "Young Frankenstein"2012-04-04T18:49:40+00:00monthlyhttps://galileospendulum.org/2012/04/03/psst-want-some-science-buddy-i-got-some-right-here/2012-04-03T21:21:54+00:00monthlyhttps://galileospendulum.org/2012/04/02/history-of-the-solar-system-in-a-cleanroom/2012-04-02T17:17:00+00:00monthlyhttps://galileospendulum.org/2012/04/01/breaking-news-theory-of-everything-really-does-explain-almost-everything/https://galileospendulum.org/wp-content/uploads/2012/04/butt_feynman.pngFeynman diagram for BUTTA typical Feynman diagram for the interaction between an electron and yo momma in the Bacfarc unified tackyon theory (BUTT).2012-04-02T04:44:24+00:00monthlyhttps://galileospendulum.org/2012/03/31/a-most-disappointing-opera/2012-06-22T12:31:57+00:00monthlyhttps://galileospendulum.org/2012/03/29/i-dreamed-i-had-a-good-job-and-i-was-well-paidi-blew-it-all-at-the-penny-arcade/https://galileospendulum.org/wp-content/uploads/2012/03/great_red_spot_jonsson_small.jpgGreat Red Spot, as seen by Voyager 2 (processed by Bjorn Jonsson)2012-06-24T14:52:03+00:00monthlyhttps://galileospendulum.org/2012/03/28/are-humans-necessary/2012-06-27T04:32:11+00:00monthlyhttps://galileospendulum.org/2012/03/27/vesta-and-the-taxonomy-of-planetology/https://galileospendulum.org/wp-content/uploads/2012/03/vesta_big.jpgthe asteroid VestaThe asteroid Vesta, as seen by the Dawn space probe.2012-11-24T01:34:48+00:00monthlyhttps://galileospendulum.org/2012/03/22/on-the-origin-of-things/https://galileospendulum.org/wp-content/uploads/2012/03/m95sn2012aw.jpgSupernova 2012awSupernova 2012aw in the spiral galaxy M95. The supernova itself is the bright blue point of light to the right of the galactic center. The galaxy is about 38 million light years away, so though the light is just reaching us now, the star that exploded is long gone. (For more information, see http://apod.nasa.gov/apod/ap120322.html)2012-03-22T17:12:25+00:00monthlyhttps://galileospendulum.org/2012/03/21/the-natural-life-cycle-of-a-physicist/https://galileospendulum.org/wp-content/uploads/2012/03/physicist_life_cycle_panel.gifpanel from Saturday Morning Breakfast Cereal2012-03-21T13:03:25+00:00monthlyhttps://galileospendulum.org/2012/03/20/sunrise-sunrise-sunset-sunset-is-this-the-little-bug-eyed-tentacled-thing-i-carried/https://galileospendulum.org/wp-content/uploads/2012/03/kepler-35b.pnga toy circumbinary system based on Kepler-35bA simplified circumbinary exoplanet system based on Kepler-35b. (The main simplification involves making all orbits circular, and drawing both stars and planet to be much larger than they really are.)2012-07-11T18:14:52+00:00monthlyhttps://galileospendulum.org/2012/03/20/y-kant-matthew-read/2012-03-20T13:28:59+00:00monthlyhttps://galileospendulum.org/2012/03/19/moonday-big-trouble-on-little-mimas/https://galileospendulum.org/wp-content/uploads/2012/03/mimas_comparison.pngMimas comparisonMimas along its longest axis is only about 3% of the diameter of Earth.https://galileospendulum.org/wp-content/uploads/2012/03/earth_herschel.jpgEarth with a crater comparable to Herschel superimposedEarth shown with a crater comparable to Herschel superimposed. Note that nearly all of North America is covered by the crater; whatever impact hit Mimas was relatively much larger than the late Cretaceous impact that played a role in the dinosaur extinctions.https://galileospendulum.org/wp-content/uploads/2012/03/mimas_double.pngTwo images of MimasTwo images of Mimas from the Cassini mission. The first shows Mimas near Saturn's rings, while the second highlights the huge Herschel crater.2012-07-22T06:22:54+00:00monthlyhttps://galileospendulum.org/2012/03/16/neutrinos-wishful-thinking-and-the-sloth-of-science/https://galileospendulum.org/wp-content/uploads/2012/03/icarus.pngICARUS results, with OPERA results for comparisonICARUS results, with OPERA results for comparison. The point labeled 0 on the horizontal axis represents neutrinos moving exactly at the speed of light; data left of that are slower than light, while to the right is that pesky faster-than-light result. Note that while the ICARUS results could still allow neutrinos to move faster than light, there is absolutely no overlap between the two sets of data. This means the two results can't both be correct - though they could both be wrong!2012-03-22T14:31:12+00:00monthlyhttps://galileospendulum.org/2012/03/16/conjunction-junction/https://galileospendulum.org/wp-content/uploads/2012/03/conjunction_diagram.pnghow conjunctions happenHow conjunctions happen: even though Venus and Jupiter are far apart, our line of sight connects them.https://galileospendulum.org/wp-content/uploads/2012/03/stellarium_solar_system_top.png"top view" of our Solar System"Top view" of our Solar System as of 8:30 on March 15, 2012. The planets all orbit in the counterclockwise direction from this perspective; Earth also rotates on its axis in the counterclockwise direction, so Venus and Jupiter appear to set in the West a few hours after the Sun does. Mars rises in the East a little before sunset, so it's very visible throughout the night.https://galileospendulum.org/wp-content/uploads/2012/03/stellarium_conjunction.pngconjunction of Venus and JupiterThe conjunction of Venus and Jupiter, as visualized by the Stellarium home planetarium software.2012-03-16T15:03:34+00:00monthlyhttps://galileospendulum.org/2012/03/13/return-of-son-of-the-link-roundup/https://galileospendulum.org/wp-content/uploads/2012/03/enceladus_silhouette.jpgEnceladus in silhouetteSaturn's moon Enceladus in silhouette, showing a cryovolcanic plume near the south pole.2012-03-13T12:51:34+00:00monthlyhttps://galileospendulum.org/2012/03/12/moonday-the-face-of-fear/https://galileospendulum.org/wp-content/uploads/2012/03/deimos.jpgDeimosMars' second moon Deimos, as seen by the Mars Reconnaissance Orbiter.https://galileospendulum.org/wp-content/uploads/2012/03/phobos_comparison.pngPhobos compared to EarthPhobos compared to Earth. Deimos is even smaller (only about a pixel at this resolution).https://galileospendulum.org/wp-content/uploads/2012/03/phobos_big.jpgPhobosPhobos, the largest of Mars' two moons. The huge indentation at the right of the image is Stickney crater.2012-03-12T19:06:29+00:00monthlyhttps://galileospendulum.org/2012/03/09/the-temperature-of-history/https://galileospendulum.org/wp-content/uploads/2012/03/entropy_evolution.pngdispersion of gasThe dispersion of gas in a container tells the story of entropy.https://galileospendulum.org/wp-content/uploads/2012/03/heat_flow.pngHeat flowTop: heat energy flows spontaneously from the container with high temperature gas to the one with lower temperature gas, until they both reach the same temperature. However, as the bottom row shows, if they both start at the same temperature, they'll stay that way forever. Heat flow is not a reversible process.2012-03-13T12:55:12+00:00monthlyhttps://galileospendulum.org/2012/03/06/i-have-this-duty/2012-03-07T02:10:24+00:00monthlyhttps://galileospendulum.org/2012/03/01/me-ludwig-boltzmann-ludwig-boltzmann-and-i/2012-04-26T23:15:24+00:00monthlyhttps://galileospendulum.org/2012/02/27/moonday-the-tao-of-iapetus/https://galileospendulum.org/wp-content/uploads/2012/02/iapetus_comparison.pngIapetus compared to Earth and the MoonIapetus compared to Earth and the Moon. It's not spherical, but the diameter at its equator is slightly less than half that of the Moon. However, since it is composed largely of ice, its mass is a lot less than a rocky body of the same size would be.https://galileospendulum.org/wp-content/uploads/2012/02/iapetus_orbit.pngThe orbit of IapetusThe orbit of Iapetus, showing the distinction between the leading edge and trailing edge. Sizes are not to scale!https://galileospendulum.org/wp-content/uploads/2012/02/iapetus_both_sides.jpgthe two sides of IapetusThe two sides of Iapetus: the leading edge (left), which is darker in color and exhibits an odd equatorial ridge, while the trailing edge is an icy white color. The moon is also distinctly non-spherical.2012-02-27T16:59:24+00:00monthlyhttps://galileospendulum.org/2012/02/23/tangled-up-in-quantum-mechanics/https://galileospendulum.org/wp-content/uploads/2012/02/bell_experiment.pngSchematic of the entanglement experiment.Schematic of the entanglement experiment.https://galileospendulum.org/wp-content/uploads/2012/02/two_photons.pngone photon goes in, two come outInverse Thunderdome: one photon goes in, two come out. The two top pictures are a schematic of a laser shining on a crystal, which then emits two. The bottom two pictures are a schematic of the internal quantum transition. The two new photons have correlated polarizations: they are entangled.2013-08-15T17:48:03+00:00monthlyhttps://galileospendulum.org/2012/02/19/long-live-the-revolution/https://galileospendulum.org/wp-content/uploads/2012/02/copernicus_revolution_big.jpgCopernicus: Long Live the Revolution!Copernicus helped us realize Earth isn't the center of the Universe. This was one of many scientific ideas that helped overthrow our arrogant assumption that humans occupy a special place in the Universe. However, the anthropocentric view still holds on in our minds; Copernicus' revolution is not yet done.2012-02-19T15:14:40+00:00monthlyhttps://galileospendulum.org/2012/02/17/the-genome-of-the-universe/https://galileospendulum.org/wp-content/uploads/2012/02/powerspectrumbreakdown.jpgCMB power spectrumThe CMB power spectrum, with the three "peaks" highlighted. The first peak indicates the total amount of "stuff" in the Universe - everything together, and the second peak is the contribution from ordinary matter. The third peak is all matter together: that's what reveals how much dark matter there is in the Universe. For more details, please see my previous post.https://galileospendulum.org/wp-content/uploads/2012/02/cmb_small.pngthe Cosmic Microwave BackgroundThe cosmic microwave background, mainly because I love this image. See yesterday's blog post for more information. [Credit: NASA/WMAP Science Team]https://galileospendulum.org/wp-content/uploads/2012/02/expansion.pngexpansion of the universeExpansion of the cosmic box, from the Big Bang until today. This post is most concerned with the second and third boxes from the top, before any galaxies or stars.2012-02-19T15:27:10+00:00monthlyhttps://galileospendulum.org/2012/02/16/the-meteorites-in-the-nations-attic/https://galileospendulum.org/wp-content/uploads/2012/02/meteorite_clean_room.jpgin the meteorite clean roomThe sexy outfit I had to wear to enter the clean room housing the Smithsonian Antarctic meteorite collection. The white oblong objects in the foreground are inverted gloves, used for reaching into the chambers where the meteorites are kept, isolated from most contaminants. (Photo by Michelle Banks.)2012-02-17T17:00:16+00:00monthlyhttps://galileospendulum.org/2012/02/14/dear-science/2012-02-17T04:44:00+00:00monthlyhttps://galileospendulum.org/2012/02/12/pithecanthropus-erectus/2012-02-13T01:07:37+00:00monthlyhttps://galileospendulum.org/2012/02/12/happy-birthday-charles-darwin-2/2012-02-12T14:19:41+00:00monthlyhttps://galileospendulum.org/2012/02/09/compact-cute-critter-communication/2012-02-10T14:28:20+00:00monthlyhttps://galileospendulum.org/2012/02/07/spinning-electron-got-to-go-round/https://galileospendulum.org/wp-content/uploads/2012/02/spinor_comic.jpgspinor comic stripHowever, two full rotations of the ball can be untangled: loop the top elastic twist around the ball, in the opposite direction from the way you rotated the ball. Then stretch the lower elastic up over the ball so that it escapes from the loop created by the upper elastic and voila! everything is back in its initial state!https://galileospendulum.org/wp-content/uploads/2012/02/one_twist.jpgsingle twistRotating the ball by 360 degrees (one twist) can't be untangled. Even though the ball is facing the same direction as it started, the entire system is not in an equivalent state.https://galileospendulum.org/wp-content/uploads/2012/02/no_twist.jpgelectron modelMy quick-and-dirty electron model, made from scrap wood, elastic, and a styrofoam ball. Note the repair in the string where my cats chewed through it. Stern and Gerlach didn't have to put up with that sort of thing!2012-02-07T17:54:01+00:00monthlyhttps://galileospendulum.org/2012/02/03/humanity-is-my-beat/2012-03-01T03:20:14+00:00monthlyhttps://galileospendulum.org/2012/02/02/happy-groundhog-day-2/2012-02-02T23:30:17+00:00monthlyhttps://galileospendulum.org/2012/01/31/fractals-for-fun/https://galileospendulum.org/wp-content/uploads/2012/01/koch_area.pngkoch_areahttps://galileospendulum.org/wp-content/uploads/2012/01/koch_comic.pngConstructing the Koch snowflakeConstructing the von Koch snowflake: the first three steps. A "true" von Koch snowflake would involve repeating this process an infinite number of times.https://galileospendulum.org/wp-content/uploads/2012/01/koch_construction.pngconstruction of von Koch snowflakeConstruction of the von Koch snowflake, first step. Take an equilateral triangle and on each side, cut out the middle third like a gate. Add a new piece where the gap was, and you have a new shape.2012-02-01T02:04:07+00:00monthlyhttps://galileospendulum.org/2012/01/29/a-mathematical-prelude-and-fugue/2012-01-31T05:03:23+00:00monthlyhttps://galileospendulum.org/2012/01/24/theres-not-a-word-yet-for-old-friends-whove-just-met/https://galileospendulum.org/wp-content/uploads/2012/01/dino_and_me.jpgExit, pursued by a tyrannosaurExit, pursued by a tyrannosaur. (Photo by Greg Gbur.)https://galileospendulum.org/wp-content/uploads/2012/01/stegosaur_medium.jpgStegosaurus...in space!Stegosaurus...in space! Artwork by the amazing Katy Chalmers.2012-01-24T18:20:01+00:00monthlyhttps://galileospendulum.org/2012/01/19/fear-of-a-math-planet/2012-01-19T19:50:10+00:00monthlyhttps://galileospendulum.org/2012/01/18/im-not-dead-yet/2012-01-18T16:15:25+00:00monthlyhttps://galileospendulum.org/2012/01/16/moonday-the-largest-of-moons/https://galileospendulum.org/wp-content/uploads/2012/01/palimpsest.jpgA palimpsestA palimpsest on Ganymede: a crater that filled with melted water from the impact, which subsequently refroze, leaving a lighter-colored region.https://galileospendulum.org/wp-content/uploads/2012/01/ganymede_medium.jpgGanymede as seen from the Galileo probeGanymede as seen from the Galileo probe. The dark coloration is due to sulfur dioxide, also seen on Io.https://galileospendulum.org/wp-content/uploads/2012/01/ganymede_comparison.pngGanymede compared to Earth and the MoonGanymede compared to Earth and the Moon.2012-01-16T18:58:19+00:00monthlyhttps://galileospendulum.org/2012/01/12/you-gotta-fight-for-your-right-to-access/2012-01-13T03:40:07+00:00monthlyhttps://galileospendulum.org/2012/01/10/switches-oscillators-yeast-cells-magnets-earthquakes-cancer-cells-brains/https://galileospendulum.org/wp-content/uploads/2012/01/plosone_fig1.pngPlots for the four possible behaviors of our modelPlots for the four possible behaviors of our model, taken from the published paper. Each pair of plots (a, b, c, and d) goes with the corresponding item in the list from the text. The lines in the top plot are correlations: a value of 1 means the switches are all "on" and the oscillators are acting together, while 0 means "off" switches and oscillators not in concert. The bottom plot is the phase of the oscillators: if it's a constant value, the oscillators have frozen out, but if it changes in a regular way, they are synchronized.https://galileospendulum.org/wp-content/uploads/2012/01/friction.pngstatic friction is analogous to a switchStatic friction can make things act somewhat like a switch: you have to build up enough force to get a table moving across a carpet. Below a threshold force, the table won't move, but above that threshold it can. The unmoving table is the switch in its "off" state, and the moving table is "on".2012-01-10T21:26:36+00:00monthlyhttps://galileospendulum.org/2012/01/09/grail-the-search-for-the-holy-moonsplat/https://galileospendulum.org/wp-content/uploads/2012/01/geneviecc80ve_de_messiecc80res.jpegGeneviève de Messièreshttps://galileospendulum.org/wp-content/uploads/2012/01/20120106moon_small.jpgThe near side of the Moon2012-01-09T19:11:16+00:00monthlyhttps://galileospendulum.org/2012/01/07/you-yes-you-are-an-astronomer/2012-01-07T16:14:04+00:00monthlyhttps://galileospendulum.org/2012/01/05/a-bit-of-good-news-and-links/2012-05-23T15:13:16+00:00monthlyhttps://galileospendulum.org/2012/01/04/time-to-make-the-paper-donuts/https://galileospendulum.org/wp-content/uploads/2012/01/projective_plane.jpgprojective planeThe projective plane, in paper form.https://galileospendulum.org/wp-content/uploads/2012/01/klein_bottle.jpgmaking the Klein bottleMaking a Klein bottle: the long arm from the template is twisted back on itself like a Möbius strip, while the shorter arm is left as it is like a cylinder.https://galileospendulum.org/wp-content/uploads/2012/01/klein_bottle1.pngtemplate for a Klein bottleTemplate for a paper Klein bottle; click to get the full-sized image. If you print it, set your printer for landscape mode and make sure the image goes all the way to the edges of the paper for best results.https://galileospendulum.org/wp-content/uploads/2012/01/torus_template1.pngtemplate for a torusTemplate for a paper torus; click to get the full-sized image. If you print it, set your printer for landscape mode and make sure the image goes all the way to the edges of the paper for best results.https://galileospendulum.org/wp-content/uploads/2012/01/klein_bottle.pngtemplate for a Klein bottleTemplate for a Klein bottle; click to get the full sized image. If you print it, make sure you print to the edge of the paper for best results.https://galileospendulum.org/wp-content/uploads/2012/01/torus_construction.jpgConstructing a torusConstructing a torus. If you can come up with a better design, please feel free to send it to me - I'm open to other ideas!https://galileospendulum.org/wp-content/uploads/2012/01/torus_template.pngtorus templateTemplate for a torus; click to get the full-sized image. When printing, make sure you print the image to fill the whole paper for best results.https://galileospendulum.org/wp-content/uploads/2012/01/torus.jpgtorus2012-01-04T15:26:22+00:00monthlyhttps://galileospendulum.org/2012/01/02/a-titanic-moonday/https://galileospendulum.org/wp-content/uploads/2012/01/titan_lakes.jpgLakes of methane on TitanMethane lakes on Titan, as imaged by Cassini using infrared light. Kraken Mare is the dark region at the very top of the image; click for more information.https://galileospendulum.org/wp-content/uploads/2012/01/titan_surface.jpgthe surface of TitanThe surface of Titan, as photographed by the Huygens lander. Much of the surface contains water ice, hard as mineral-based rocks on Earth.https://galileospendulum.org/wp-content/uploads/2012/01/titan_comparison.pngTitan compared with Earth and the MoonTitan compared with Earth and the Moon. Titan is the second-largest moon in the Solar System, larger than our Moon and the planet Mercury.https://galileospendulum.org/wp-content/uploads/2012/01/titan.jpgTitanSaturn's largest moon, Titan, along with icy moon Tethys and Saturn's rings. Note how hazy Titan's atmosphere is; some of the same chemicals are present in smog on Earth.2012-01-02T19:59:12+00:00monthlyhttps://galileospendulum.org/2012/01/02/happy-birthday-isaac-asimov/https://galileospendulum.org/wp-content/uploads/2012/01/isaac_asimov.jpgIsaac Asimov (born January 2, 1920)Isaac Asimov, born January 2, 1920. He wrote hundreds of books, both fiction and non-fiction, popularizing science while sporting sideburns to make Victorians jealous.2012-01-02T15:20:22+00:00monthlyhttps://galileospendulum.org/2011/12/30/2011-a-year-of-oscillation/2011-12-31T14:50:57+00:00monthlyhttps://galileospendulum.org/2011/12/27/happy-birthday-johannes-kepler/https://galileospendulum.org/wp-content/uploads/2011/12/orbit.pngElliptical orbit in Kepler's systemElliptical orbit of a planet around the Sun. Note that the Sun isn't at the center of the ellipse but at a special point called a focus. I've exaggerated how eccentric the orbit is for clarity; planets in our Solar System follow paths that are closer to being circular.2012-04-09T17:06:48+00:00monthlyhttps://galileospendulum.org/2011/12/27/hearing-around-corners/https://galileospendulum.org/wp-content/uploads/2011/12/photo-43.jpgExperiments in Topology by Stephen BarrExperiments in Topology by Stephen Barr, a book I found in a second-hand bookstore last week. Math with paper and scissors!2011-12-27T21:25:24+00:00monthlyhttps://galileospendulum.org/2011/12/22/happy-birthday-grote-reber/https://galileospendulum.org/wp-content/uploads/2011/12/grote_reber_radio_telescope.jpgGrote Reber's radio telescopeGrote Reber's radio telescope, now at NRAO in Green Bank, West Virginia.https://galileospendulum.org/wp-content/uploads/2011/12/grote_reber.gifgrote_reber2011-12-22T15:30:54+00:00monthlyhttps://galileospendulum.org/2011/12/21/its-dangerous-to-go-alone-take-this/2011-12-24T06:08:22+00:00monthlyhttps://galileospendulum.org/2011/12/23/mirror-mirror-on-the-wall-mirrors-dont-switch-hands-at-all/https://galileospendulum.org/wp-content/uploads/2011/12/passenger_mirror.jpgpassenger-side mirror on a carThe famous words on a passenger-side mirror, marking it as a convex mirror.https://galileospendulum.org/wp-content/uploads/2011/12/wizard_spoon_convex.jpgThe wizard reflected in a spoonThe bowed-out side of a spoon is a convex mirror. You can see the image of the wizard is upright, with back-and-front reversed as with the flat mirror. However, he's a little distorted and his image appears farther away.https://galileospendulum.org/wp-content/uploads/2011/12/converging.pngconvergingA concave mirror actually produces an image in front of the mirror, which is why the eye has so much trouble focusing on it. Unlike a flat mirror, a concave mirror does flip left and right as well as up and down.https://galileospendulum.org/wp-content/uploads/2011/12/wizard_mirror.jpgThe wizard in the mirrorYou see the back of the LEGO wizard, but the mirror shows his front. That's why mirrors flip front and back, not left and right.2011-12-21T00:38:22+00:00monthlyhttps://galileospendulum.org/2011/12/20/hot-rocks-the-smallest-exoplanets-yet-discovered/https://galileospendulum.org/wp-content/uploads/2011/12/kepler-20.jpgKepler-20Comparison of the sizes of Kepler-20e, Kepler-20f, Earth, and Venus (in an artist's impression).2012-01-05T14:39:29+00:00monthlyhttps://galileospendulum.org/2011/12/20/teaching-were-doin-it-rong-links-for-12192011/https://galileospendulum.org/wp-content/uploads/2011/12/saturn_is_big.jpgSaturn is big!Saturn is big!2011-12-20T13:34:41+00:00monthlyhttps://galileospendulum.org/2011/12/19/w-k-clifford-the-geometry-of-physics/https://galileospendulum.org/wp-content/uploads/2011/12/trivector.pngtrivectorhttps://galileospendulum.org/wp-content/uploads/2011/12/3d_planes1.pngplanes of rotation in 3 dimensionsPlanes of rotation in three dimensions, labeled with the quaternion units.https://galileospendulum.org/wp-content/uploads/2011/12/clifford_multiplication.pngclifford_multiplicationhttps://galileospendulum.org/wp-content/uploads/2011/12/3d_planes.pngPlanes of rotation in 3 dimensionsPlanes of rotation in three dimensions, labeled with the quaternion units.https://galileospendulum.org/wp-content/uploads/2011/12/bivector.pngBivectorRotation in the counterclockwise direction is the multiplication of j and k; reversing the order gives clockwise rotation. Usually it's simpler to draw the bivector as a circle, though, since what we're really after is the sense of rotation.https://galileospendulum.org/wp-content/uploads/2011/12/euler.pngEulerhttps://galileospendulum.org/wp-content/uploads/2011/12/2d_rotation.pngRotations using the quaternion iRotating the velocity using the third quaternion unit i.https://galileospendulum.org/wp-content/uploads/2011/12/quaternion_multiplication.pngquaternion multiplicationhttps://galileospendulum.org/wp-content/uploads/2011/12/hamiltons_formula.pngHamiltons_formulahttps://galileospendulum.org/wp-content/uploads/2011/12/2d_quaternion.pnghow eastish and northish the car is travelingHow fast is the car moving to the east? How fast is it moving to the north? To get those answers, we split the vector into east-west and north-south pieces, called components. Here we label them using the quaternion imaginary units.2011-12-21T21:39:05+00:00monthlyhttps://galileospendulum.org/2011/11/16/the-great-lakes-of-europa/https://galileospendulum.org/wp-content/uploads/2011/11/europa_chaos_formation.pngFormation of chaos regions on EuropaThe four-step process in the proposed chaos terrain formation model. a. A plume from a hydrothermal vent rises toward the thick ice layer on Europa's surface. b The ice melts where the plume meets it, forming a lake and stressing the ice above and around it. The result is a sunken region. c The fractures produce floating blocks of ice; the energy of the plume disperses. d The lake refreezes, pushing the blocks of ice up and forming a highland region.https://galileospendulum.org/wp-content/uploads/2011/11/thera_macula.pngThera MaculaThera Macula, a slightly sunken region on Europa that may be where chaos terrain is actively being formed. This image is false color, with the darker region in the center indicating below the average surface height, and maroon indicating slightly elevated regions.https://galileospendulum.org/wp-content/uploads/2011/11/europa.jpgEuropaJupiter's moon Europa, which is slightly smaller than Earth's Moon. The surface is mostly ice water, smooth and without major craters.2011-12-19T15:41:03+00:00monthlyhttps://galileospendulum.org/2011/11/23/moons-and-junes-and-ferris-wheels/https://galileospendulum.org/wp-content/uploads/2011/11/tvashtar1.jpgvolcanic eruption on IoThe New Horizons probe, headed for Pluto, took this picture of the Tvashtar volcano erupting on Io in 2007. Note the size of the plume compared to the size of the moon!https://galileospendulum.org/wp-content/uploads/2011/11/iotorus.gifIo torusDonut-shaped region of ejected gas from Io as it orbits Jupiter. The central part of the image is masked so that the light from Jupiter doesn't swamp the relatively faint torus.https://galileospendulum.org/wp-content/uploads/2011/11/05-io.jpgIo, a moon of JupiterJupiter's moon Io, the closest of the Galilean moons. The surface features are dominated by volcanoes and their output; the yellow color is from sulfur compounds.2011-12-19T15:40:45+00:00monthlyhttps://galileospendulum.org/2011/11/28/moonday-moonday/https://galileospendulum.org/wp-content/uploads/2011/11/io_europa_comparison.pngcomparison of Io and Europa to Earth and its MoonComparison of the sizes of Io and Europa to Earth and its Moon. Note that Io is slightly larger than the Moon, while Europa is slightly smaller.2011-12-19T15:40:35+00:00monthlyhttps://galileospendulum.org/2011/12/05/moonday-volcanoes-of-ice/https://galileospendulum.org/wp-content/uploads/2011/12/enceladus_tiger_stripes.jpgtiger stripes"Tiger stripes": volcanic fissures on Enceladus.https://galileospendulum.org/wp-content/uploads/2011/12/cryovolcano.jpgcryovolcanoJets of water and ice shooting up from a tiger stripe on Enceladus. These volcanoes are known as cryovolcanoes, meaning "volcanoes of ice".https://galileospendulum.org/wp-content/uploads/2011/12/enceladus-large.jpgEnceladus, a moon of SaturnEnceladus, an icy moon of Saturn. 99% of the light falling on Enceladus is reflected back into space, making it possibly the most reflective object in the Solar System.https://galileospendulum.org/wp-content/uploads/2011/12/enceladus_comparison.pngEnceladus size comparison to Earth and its MoonEnceladus is tiny compared to Earth and its Moon.2011-12-19T15:39:08+00:00monthlyhttps://galileospendulum.org/2011/12/16/are-we-afraid-to-teach-truly-exciting-science/https://galileospendulum.org/wp-content/uploads/2011/12/soapbox.jpgsoapbox2011-12-20T13:24:39+00:00monthlyhttps://galileospendulum.org/2011/12/15/prelude-to-feynman-diagrams/https://galileospendulum.org/wp-content/uploads/2011/12/moller_feynman_tree.pngFeynman diagram for Moeller scatteringOne possible Feynman diagram for electron-electron scattering.https://galileospendulum.org/wp-content/uploads/2011/12/moller.pngElectron-electron scatteringElectron-electron scattering: despite the simplicity of the basic diagram, a lot can happen inside that yellow circle! (I'm going to follow the usual convention from now on and drop the "space" and "time" axes, along with the "speed of light" line. Just imagine they're there, because they are.)https://galileospendulum.org/wp-content/uploads/2011/12/classical_collision.pngCollision of two ballsSpacetime diagram for the collision between two distinguishable balls.https://galileospendulum.org/wp-content/uploads/2011/12/wall.pngspacetime diagram of a ball bouncing off a wallA spacetime diagram for a ball bouncing off a wall, along with a comic strip showing the same thing.https://galileospendulum.org/wp-content/uploads/2011/12/spacetime_diagram.pngSpacetime diagramA spacetime diagram containing several possible trajectories for particles with mass, and one impossible trajectory. A photon will follow a trajectory along the line marked "speed of light".2011-12-16T18:06:00+00:00monthlyhttps://galileospendulum.org/2011/12/15/the-shadow-of-your-earth/2011-12-15T14:23:29+00:00monthlyhttps://galileospendulum.org/2011/12/14/surely-youre-comics-mr-feynman/https://galileospendulum.org/wp-content/uploads/2011/12/feynman.jpgFeynman by Ottaviani and Myrick2011-12-14T17:08:24+00:00monthlyhttps://galileospendulum.org/2011/12/13/the-fault-dear-brutus-is-not-in-our-detectors-but-in-ourselves/2012-03-04T00:50:13+00:00monthlyhttps://galileospendulum.org/2011/12/12/links-on-trust-vaccination-and-pseudoscience/2012-03-15T00:02:33+00:00monthlyhttps://galileospendulum.org/2011/12/11/from-the-height-of-the-pacific-to-the-depths-of-everest/https://galileospendulum.org/wp-content/uploads/2011/12/kansas_panorama_small_2.jpgKansas panorama #2: "flat as a pancake? Ha!"https://galileospendulum.org/wp-content/uploads/2011/12/kansas_panorama__small_1.jpgKansas panorama #1: "look at that mount!"2011-12-11T19:42:50+00:00monthlyhttps://galileospendulum.org/2011/12/09/the-most-striking-equation-in-mathematics/https://galileospendulum.org/wp-content/uploads/2011/12/wavefunction.pngwavefunctionhttps://galileospendulum.org/wp-content/uploads/2011/12/quaternion_rotations.pngquaternion_rotationshttps://galileospendulum.org/wp-content/uploads/2011/12/coordinate_rotation.pngcoordinate_rotationhttps://galileospendulum.org/wp-content/uploads/2011/12/square_rotation.pngrotating a square using complex numbersRotating a square using complex numbers. For details, see my earlier post, "The Most Striking Equation in Mathematics".https://galileospendulum.org/wp-content/uploads/2011/12/rotation.pngrotationhttps://galileospendulum.org/wp-content/uploads/2011/12/polar.pngpolarhttps://galileospendulum.org/wp-content/uploads/2011/12/leonhard_euler.jpgLeonhard EulerLeonhard Euler, one of the greatest mathematicians of all time. He also contributed to physics, astronomy, and the fashion of wearing boxer shorts on his head. https://galileospendulum.org/wp-content/uploads/2011/12/sine_cosine.pngsine_cosinehttps://galileospendulum.org/wp-content/uploads/2011/12/complex_plane.pngrelating a circle to complex numbersRelating a circle to complex numbers. The radius line (in blue) has a length of 1, and we'll use that as the hypotenuse of a triangle. Then the x- and y-coordinates of the end of the line are given by the cosine and sine of the angle as shown.https://galileospendulum.org/wp-content/uploads/2011/12/normalization.pngnormalization2011-12-12T14:53:27+00:00monthlyhttps://galileospendulum.org/2011/12/09/more-poll-ish-than-marie-sklodowska-curie-and-copernicus-put-together/2011-12-10T19:22:02+00:00monthlyhttps://galileospendulum.org/2011/12/08/of-winters-and-water/https://galileospendulum.org/wp-content/uploads/2011/12/habitable1.pngtwo possible complications for habitable zones and elliptical orbitsTwo possible complications for habitable zones and elliptical orbits. In the top picture, the planet is in the habitable zone for its periastron but not its apastron, while in the second case it passes through the habitable zone, but is too hot at periastron and too cold at apastron.https://galileospendulum.org/wp-content/uploads/2011/12/ellipse.pngcircular and elliptical orbitsCircular and elliptical orbits of the "same size": the average between the planet and the host star is the same in both orbits, so they take the same amount of time to orbit. However, at the farthest point in the elliptical orbit (the apastron), the planet is significantly farther from the star than at its closest approach (the periastron).2011-12-10T18:51:27+00:00monthlyhttps://galileospendulum.org/2011/12/07/the-universe-is-mostly-flat/https://galileospendulum.org/wp-content/uploads/2011/12/inflation_comic1.jpgillustrating inflation using a beach ball[caption]https://galileospendulum.org/wp-content/uploads/2011/12/inflation_comic.jpginflation illustrated using a beach ballInflation illustrated using a beach ball. Initially, the geometry of the universe is messy, but inflation smooths out the differences in separate regions, making everything the same. After inflation ends, the universe will be mostly flat, though you'd have to zoom in closer than I was able to do with this particular beach ball (or just get a bigger ball).https://galileospendulum.org/wp-content/uploads/2011/12/geometry.pngpossible geometries of the universeThe three possible geometries for a homogeneous and isotropic universe. They are the four-dimensional extensions of spherical, Euclidean, and hyperbolic geometries, respectively. The names refer to whether initially parallel light trajectories converge (close), stay parallel (flat), or diverge (open).2013-01-08T14:46:28+00:00monthlyhttps://galileospendulum.org/2011/10/10/im-happy-as-canby/https://galileospendulum.org/wp-content/uploads/2011/10/phantom_tollbooth.pngThe Phantom Tollbooth by Norton JusterThe Phantom Tollbooth by Norton Juster.2011-12-07T17:31:36+00:00monthlyhttps://galileospendulum.org/2011/10/25/out-out-brief-candle/2011-12-07T17:31:05+00:00monthlyhttps://galileospendulum.org/2011/01/25/william-shakespeare-and-the-moon-landings/2011-12-07T17:30:41+00:00monthlyhttps://galileospendulum.org/2011/10/24/the-universe-in-a-box-part-1/https://galileospendulum.org/wp-content/uploads/2011/10/expansion_animation2.gifExpansion animation version 2https://galileospendulum.org/wp-content/uploads/2011/10/expansion_animation1.gifexpansion animation (version 1)Cosmic expansion animation, redux: note that the expanding boxes represent how the universe actually is at a given moment in time.https://galileospendulum.org/wp-content/uploads/2011/10/filmstrip2_small.pngCosmic expansion from another frame of referenceThe same frames as the previous image, but this time viewing from the point of view of the lower-left galaxy. The boxes are expanding at the same rate as before; the picture only looks different because of our change in perspective, not because anything about the universe itself has changed. Observers in any galaxy will see every other galaxy moving away.https://galileospendulum.org/wp-content/uploads/2011/10/filmstrip_small1.pngExpansion of the universe (comic strip version)A large group of cosmic boxes packed together. I only included three galaxies and made them far too big for simplicity's sake. The galaxy closest to the center represents the Milky Way (our frame of reference). As time progresses, each box grows larger but the galaxies don't; because each galaxy is "attached" to its own box, they all get farther apart as the cubes grow.https://galileospendulum.org/wp-content/uploads/2011/10/filmstrip_small.pngExpansion of the universehttps://galileospendulum.org/wp-content/uploads/2011/10/box.pngCosmic boxA cosmic cube, with sides 500 million light-years long. Each face is part of the 2dF survey, so each yellow blob represents a real galaxy. With a cube this large, you can begin to see why cosmologists claim the universe is homogeneous: the cube is fairly uniformly yellow.https://galileospendulum.org/wp-content/uploads/2011/10/2dfzcone.png2-Degree Field (2dF) galaxy surveyThe 2-degree Field (2dF) galaxy survey by the Anglo-Australian Observatory counted all the galaxies in a 2-degree swath of the sky. (For comparison, the Moon is about 1/2 degree wide.) Each purple dot is a galaxy, so you can see that with a large enough box, the universe looks fairly smooth, even though it decidedly is not on smaller scales.https://galileospendulum.org/wp-content/uploads/2011/10/lss_z0.gifA smaller cosmic boxA simulated cosmic box 43 million parsecs on each side. It's smaller than the one I'm considering, but you can imagine making a bigger cube out of 27 of these. The blue dots are clumps of dark matter. (From the University of Chicago; click the picture for even more images and movies.)2011-12-07T17:24:48+00:00monthlyhttps://galileospendulum.org/2011/10/26/the-universe-in-a-box-part-2-opening-the-box/https://galileospendulum.org/wp-content/uploads/2011/10/redshift.pngredshiftAs the cosmic box expands, it will stretch light waves, making their wavelengths longer and changing their colors.https://galileospendulum.org/wp-content/uploads/2011/10/gas_diffusion.pngdensity of gasThe total amount of matter inside the box is constant, so as the box expands, the density of matter goes down dramatically.https://galileospendulum.org/wp-content/uploads/2011/10/acceleration.gifaccelerationhttps://galileospendulum.org/wp-content/uploads/2011/10/comparison.pngcomparison of different possible scenariosBefore 1998, most cosmologists wre fairly certain that cosmic expansion must be decelerating, but they found acceleration instead. The difference between the possible scenarios is shown, with constant expansion added in for comparison.2011-12-07T17:24:10+00:00monthlyhttps://galileospendulum.org/2011/11/07/the-universe-in-a-box-part-3-an-incredibly-brief-history-of-time/https://galileospendulum.org/wp-content/uploads/2011/11/universe_content_320.jpgThe contents of the universe 13.7 billion years ago and today.The contents of the universe today, and 380,000 years after the Big Bang. (Image from the WMAP website.)https://galileospendulum.org/wp-content/uploads/2011/11/expansion.pngExpansion of the cosmic boxThe expansion of the cosmic box from the inflationary epoch through today. Sizes in both space and time are not to scale.https://galileospendulum.org/wp-content/uploads/2011/11/inflation.pnginflation Before inflation, the cosmic boxes weren't cubical or the same size. Inflation pumped energy into each box, smoothing out the differences and making them flat-sided and uniform.2011-12-07T17:23:43+00:00monthlyhttps://galileospendulum.org/2011/11/30/how-big-is-the-universe-universe-in-a-box-part-4/https://galileospendulum.org/wp-content/uploads/2011/11/reality_vs_appearance1.pngreality vs. appearanceReality vs. appearance for three galaxies. The white boxes enclose the galaxies as they actually are now: note that these boxes are of the same size, so they represent the same moment in time. The red boxes enclose galaxies as they appear to us: the farther away a galaxy is, the longer light has taken to travel to us, so we are looking farther into the past. The nearest galaxy, on the other hand, hasn't moved much and the size of its apparent box is about the same as it is in reality.https://galileospendulum.org/wp-content/uploads/2011/11/reality_vs_appearance.pngreality vs. appearance in cosmic expansionReality vs. appearance in cosmic expansion. The red boxes are what we see, while the white boxes show where the galaxies currently are. A galaxy that appears far away is actually proportionally even farther, since the light had to travel that much longer to reach us.2011-12-07T17:23:33+00:00monthlyhttps://galileospendulum.org/2011/12/07/reminder-the-x-files-was-fiction/2011-12-07T14:32:52+00:00monthlyhttps://galileospendulum.org/2011/12/07/the-blue-marble/https://galileospendulum.org/wp-content/uploads/2011/12/earth_apollo.jpgthe Blue MarbleThe Blue Marble: Earth, as seen from Apollo 17.2011-12-07T22:22:39+00:00monthlyhttps://galileospendulum.org/2011/12/06/what-does-habitable-mean/https://galileospendulum.org/wp-content/uploads/2011/12/kepler-22b_comparison.pngExoplanet Kepler-22b compared to Earth and NeptuneThe estimated size of exoplanet Kepler-22b (in an artist's depiction) compared with Earth and Neptune.2011-12-06T18:25:28+00:00monthlyhttps://galileospendulum.org/2011/12/04/and-that-inverted-bowl-they-call-the-sky/https://galileospendulum.org/wp-content/uploads/2011/12/rubaiyat.jpgIllustration from the first edition of FitzGerald's adaptation of Rubaiyat of Omar KhayyamIllustration by Edmund Sullivan from the first edition of FitzGerald's adaptation of Rubaiyat of Omar Khayyam. This image has famously been used in posters for The Grateful Dead.2011-12-06T14:23:59+00:00monthlyhttps://galileospendulum.org/2011/12/02/straight-lines-in-a-curvy-universe/https://galileospendulum.org/wp-content/uploads/2011/12/sphereical_hyperbolic.pngTriangles in spherical and hyperbolic geometryTriangles in spherical and hyperbolic geometry. In spherical https://galileospendulum.org/wp-content/uploads/2011/12/spherical_triangle.pngtriangle in spherical geometryA triangle in spherical geometry is constructed by taking three great circles and shading in the area they enclose. If you imagine the sphere being an orange, cut along the great circles and lay the peel out on a flat surface to get the triangle. Lines that were straight on the orange don't appear that way when laid out flat, which illustrates a difference between flat Euclidean geometry and curved non-Euclidean geometry.https://galileospendulum.org/wp-content/uploads/2011/12/great_circle.pnggreat circlesThree great circles, one corresponding to the Equator, one corresponding to a longitude line, and the third being an arbitrary one.https://galileospendulum.org/wp-content/uploads/2011/12/hyperbolic.pnghyperbolic paraboloidA hyperbolic paraboloid, which is the surface described by the hyperbolic geometry of Lobachevsky.https://galileospendulum.org/wp-content/uploads/2011/12/latitude_longitude.pnglatitude and longitude linesLatitude and longitude lines on a sphere. Note that the latitudes are parallel, but longitude lines are only parallel at the equator. There is no way to make a grid of squares on the surface of a sphere without leaving gaps or overlapping.https://galileospendulum.org/wp-content/uploads/2011/12/lobachevsky.jpgNikolai Ivanovich LobachevskyNikolai Ivanovich Lobachevsky (1792-1856), one of several mathematicians who paved the way to modern geometry - and general relativity.2011-12-02T22:26:43+00:00monthlyhttps://galileospendulum.org/2011/12/02/links-for-friday-with-bonus-brainworm/https://galileospendulum.org/wp-content/uploads/2011/12/wondermark-toothpaste-panel.pngpanel from "Wondermark"David Malki! presents a novel idea for why there always seems to be a little more toothpaste in the bottom of the tube. Click for the full comic, and make sure you read the mouseover text as well.2011-12-02T14:48:53+00:00monthlyhttps://galileospendulum.org/2011/12/01/links-for-the-new-month/2011-12-01T14:32:27+00:00monthlyhttps://galileospendulum.org/2011/11/30/wednesdays-on-jupiter/https://galileospendulum.org/wp-content/uploads/2011/11/wednesdays_on_jupiter.pngWednesdays on Jupiter - comic by Roz Chast2011-11-30T13:29:33+00:00monthlyhttps://galileospendulum.org/2011/11/29/the-soul-and-center-of-science/https://galileospendulum.org/wp-content/uploads/2011/11/2009-solvay-conference.jpg2009 Solvay ConferenceWhat's wrong with this picture?2011-11-29T19:06:12+00:00monthlyhttps://galileospendulum.org/2011/11/28/never-another-curie-and-other-links/2011-11-28T16:24:29+00:00monthlyhttps://galileospendulum.org/2011/11/23/promotion-self-and-otherwise/https://galileospendulum.org/wp-content/uploads/2011/11/mom-tattoo.jpg"Mom" tattoo2011-11-23T17:21:24+00:00monthlyhttps://galileospendulum.org/2011/11/21/new-weeks-new-projects/https://galileospendulum.org/wp-content/uploads/2011/11/scimombadgeblue.gifDouble X ScienceDouble X Science, a new blog I will be contributing to.2011-11-22T02:17:30+00:00monthlyhttps://galileospendulum.org/2011/11/19/who-needs-shark-week-lets-have-dune-week/https://galileospendulum.org/wp-content/uploads/2011/11/lunar-topography.jpglunar topographyTopographic map of the far side of the Moon, from Lunar Reconnaissance Orbiter data.2011-11-20T16:06:06+00:00monthlyhttps://galileospendulum.org/2011/11/19/saturn-day-and-the-absurdity-of-absolute-definitions/2011-11-20T01:12:06+00:00monthlyhttps://galileospendulum.org/2011/11/17/confession-i-have-no-sense-of-humor-whatsoever/https://galileospendulum.org/wp-content/uploads/2011/11/photo-17.jpgCthulhu hatThe Cthulhu hat containing the demonic spirit that ate my sense of humor, leaving me entirely bereft.2013-08-10T10:56:35+00:00monthlyhttps://galileospendulum.org/2011/11/16/i-think-the-word-youre-searching-for-is-space-ranger/https://galileospendulum.org/wp-content/uploads/2011/11/monkey_floor_polisher_panel.jpgpanel from "Cul de Sac""Theories" about the Moon, propounded by the weird and wonderful kids in "Cul de Sac". Click for the whole comic.2011-11-16T13:10:22+00:00monthlyhttps://galileospendulum.org/2011/11/15/tsunamis-of-sand-in-the-sahara/https://galileospendulum.org/wp-content/uploads/2011/11/barchan_collision.pngbarchan collisionCollision between two barchan dunes, as viewed through satellite images over 35 years (left) and in simplified cartoon form (right). The upwind dune transfers particles to the downwind dune, creating the same effect as two solitons passing through each other.https://galileospendulum.org/wp-content/uploads/2011/11/barchan.jpgbarchan dune in MoroccoA barchan dune in Morocco. Note its crescent shape, with the "horns" pointing away from the direction the wind is blowing. (Image from the New Journal of Physics.)2011-11-20T18:40:34+00:00monthlyhttps://galileospendulum.org/2011/11/15/links-for-tuesday-november-15/2011-11-15T13:48:59+00:00monthlyhttps://galileospendulum.org/2011/11/11/in-transit-like-an-exoplanet/2011-11-11T14:00:25+00:00monthlyhttps://galileospendulum.org/2011/11/09/the-nasa-you-may-not-know/https://galileospendulum.org/wp-content/uploads/2011/11/orion-upside-down2.jpgorion upside-downhttps://galileospendulum.org/wp-content/uploads/2011/11/orion-upside-down1.jpgorion upside-downhttps://galileospendulum.org/wp-content/uploads/2011/11/orion-upside-down21.jpgorion upside-downAfter landing in the impact basin, the Orion capsule tipped over, which as you can guess isn't optimal for the contents inside.https://galileospendulum.org/wp-content/uploads/2011/11/orion-upside-down.jpgorion upside-downhttps://galileospendulum.org/wp-content/uploads/2011/11/inflatable-reentry-shield.jpginflatable reentry shieldA poster for the inflatable reentry shield concept, with the edge of a miniature version made of Kevlar. (At this point in the tour, my camera's battery was running low, so I didn't get a good picture of the shield, unfortunately.)https://galileospendulum.org/wp-content/uploads/2011/11/landing-impact-gantry.jpgLanding Impact gantryA partial view of the 240-foot-tall gantry structure used to test vertical impacts, including the water impact test of the Orion capsule we were able to watch yesterday. This same structure was also used to test the Lunar Landing Module for Apollo in the 1960s.https://galileospendulum.org/wp-content/uploads/2011/11/particle-intake-nozzle.jpgparticle intake nozzleThe particle intake nozzle on a NASA research airplane. Unfortunately, the planes were being stripped down for a complete inspection, so we weren't able to see the instruments in place.2011-11-11T13:25:29+00:00monthlyhttps://galileospendulum.org/2011/11/08/splash/https://galileospendulum.org/wp-content/uploads/2011/11/orion_presplash.jpgOrion capsuleBack in 2011, I watched an early splashdown test of the Orion capsule at NASA's Langley facility. Here's the capsule on its pendulum, just before releasing it to splash into a pool of water below. [Credit: moi]2011-11-09T00:35:12+00:00monthlyhttps://galileospendulum.org/2011/11/01/update/2011-11-07T02:24:49+00:00monthlyhttps://galileospendulum.org/2011/10/31/science-is-for-everyone-including-gasp-moms/https://galileospendulum.org/wp-content/uploads/2011/10/marie_curie_c1920.pngMarie CurieMarie Curie won the Nobel Prize twice. Her daughter also won the Nobel Prize. In other words, she was one kickin' mother.2011-11-02T18:55:34+00:00monthlyhttps://galileospendulum.org/2011/10/31/happy-scienceween/https://galileospendulum.org/wp-content/uploads/2011/10/ghost_nebula.jpgghost nebulaA ghostly nebula (from Astronomy Picture of the Day).2011-10-31T13:43:21+00:00monthlyhttps://galileospendulum.org/2011/10/29/science-culture-link-roundup-october-29-2011/2011-10-29T11:34:25+00:00monthlyhttps://galileospendulum.org/2011/10/28/i-am-not-left-handed/https://galileospendulum.org/wp-content/uploads/2011/10/chirality_amino_acid.jpgchirality in an amino acidChirality in an amino acid. The "COOH" represents a general structure known as a carboxyl group; different amino acids have different combinations of carbon, oxygen, and hydrogen (hence the carb-oxy part of the name). Because the molecule is asymmetric, it has a chiral structure and comes in either left- or right-handed versions.https://galileospendulum.org/wp-content/uploads/2011/10/hand_chirality.jpgChirality of human handsChirality in human hands: even with both left and right hands oriented with fingers the same way, they aren't identical. The palm of the left hand is facing outward, while the knuckles of the right hand face outward. Or is it the other way around? I won't tell.2012-07-02T11:13:55+00:00monthlyhttps://galileospendulum.org/2011/10/27/eris-science-history-cryptography-beards/https://galileospendulum.org/wp-content/uploads/2011/10/fourmoons_cassini_small.jpgFour moons of SaturnFour moons of Saturn: Titan, Dione, Pandora, and (if you look carefully) Pan, from Cassini. Via Astronomy Picture of the Day.2011-10-27T18:16:17+00:00monthlyhttps://galileospendulum.org/2011/10/21/math-is-for-girls-and-boys-and-women-and-men/https://galileospendulum.org/wp-content/uploads/2011/10/noether-tshirt-small.pngEmmy NoetherIf girls can't do math, why was the greatest 20th century mathematician a woman? (And yes, I've used this line and image before. So sue me. But buy the t-shirt first, please.)2011-10-21T23:35:11+00:00monthlyhttps://galileospendulum.org/2011/10/21/second-verse-same-as-the-first-a-little-bit-louder-and-a-little-bit-worse/2011-10-21T20:12:30+00:00monthlyhttps://galileospendulum.org/2011/10/20/why-do-i-write/https://galileospendulum.org/wp-content/uploads/2011/10/recliner_small.jpgtwo cats in a reclinerThe other reason why I write is because my cats Harriet and Pascal hog the recliner, so I can't just laze around all day.2011-10-21T16:10:42+00:00monthlyhttps://galileospendulum.org/2011/10/20/do-all-the-science/2011-10-20T13:34:07+00:00monthlyhttps://galileospendulum.org/2011/10/18/free-energy-er-links-for-all/2011-10-18T14:24:25+00:00monthlyhttps://galileospendulum.org/2011/04/07/controversial-doesnt-mean-ideas-you-dont-like/2011-10-18T14:03:27+00:00monthlyhttps://galileospendulum.org/2011/05/08/the-texas-paradox/https://galileospendulum.org/wp-content/uploads/2011/05/sevendeadlytexans800.pngSeven Deadly Texans -- from DieselSweeties.com2011-10-18T14:01:39+00:00monthlyhttps://galileospendulum.org/2011/05/25/whose-job-is-public-science-education/https://galileospendulum.org/wp-content/uploads/2011/05/professorfrink.pngProfessor Frink from The Simpsons2011-10-18T14:01:13+00:00monthlyhttps://galileospendulum.org/2011/08/29/no-laughing-matter-mores-the-pity/2011-10-18T13:59:49+00:00monthlyhttps://galileospendulum.org/2011/09/08/galileo-still-matters/2011-10-18T13:59:03+00:00monthlyhttps://galileospendulum.org/2011/10/06/wall-street-journal-commits-epic-science-errors/2011-10-18T13:57:46+00:00monthlyhttps://galileospendulum.org/2011/10/13/thursday-before-the-journey/2011-10-18T13:57:37+00:00monthlyhttps://galileospendulum.org/2011/10/17/quickies-for-october-17-2011/2011-10-17T22:13:12+00:00monthlyhttps://galileospendulum.org/2011/10/17/why-quaternions-matter/https://galileospendulum.org/wp-content/uploads/2011/10/rotations6.pngrotations6https://galileospendulum.org/wp-content/uploads/2011/10/rotations5.pngrotations5https://galileospendulum.org/wp-content/uploads/2011/10/rotations4.pngrotations4https://galileospendulum.org/wp-content/uploads/2011/10/rotations3.pngrotations3https://galileospendulum.org/wp-content/uploads/2011/10/rotations2.pngrotations2https://galileospendulum.org/wp-content/uploads/2011/10/rotations1.pngrotations1https://galileospendulum.org/wp-content/uploads/2011/10/quaternion_example.pngquaternion_examplehttps://galileospendulum.org/wp-content/uploads/2011/10/multiplication_table.pngmultiplication_tablehttps://galileospendulum.org/wp-content/uploads/2011/10/quaternion_definition.pngquaternion_definitionhttps://galileospendulum.org/wp-content/uploads/2011/10/quaternion_algebra.pngquaternion_algebra2012-05-12T14:23:29+00:00monthlyhttps://galileospendulum.org/2011/10/14/from-way-up-here-the-earth-is-very-small/https://galileospendulum.org/wp-content/uploads/2011/10/nasa_swag_small.jpgSwag from the NASA tweetupThe other items Tweetup attendees received: a picture of the STS-135 crew, a sticker with the mission patch on it (note the capital omega frames the shuttle image, denoting the last mission), a bookmark, and other stickers with the NASA "meatball" on it.https://galileospendulum.org/wp-content/uploads/2011/10/lapel_pin_small.jpgNASA commemorative lapel pinLapel pin commemorating the 30-year-long Space Shuttle program.2011-10-17T17:04:00+00:00monthlyhttps://galileospendulum.org/2011/10/12/science-outreach-links-of-the-day/https://galileospendulum.org/wp-content/uploads/2011/10/seaofknowledge.jpgMap of the Kingdom of WisdomMap of the Kingdom of Wisdom, from The Phantom Tollbooth.2011-10-15T10:40:32+00:00monthlyhttps://galileospendulum.org/2011/10/11/links-for-tuesday/https://galileospendulum.org/wp-content/uploads/2011/10/annie_jump_cannon_tshirt_small.pngAnnie Jump Cannon t-shirtThe latest t-shirt design features Annie Jump Cannon and her famous spectral classification of stars.2011-10-11T13:59:14+00:00monthlyhttps://galileospendulum.org/2011/10/09/easy-like-sunday-morning/2011-10-09T19:16:55+00:00monthlyhttps://galileospendulum.org/2011/10/08/gives-you-the-strength-to-do-what-needs-to-be-done/https://galileospendulum.org/wp-content/uploads/2011/10/coffee_diptych.jpgcoffee mug diptych2011-10-08T14:47:01+00:00monthlyhttps://galileospendulum.org/2011/10/07/ada-lovelace-day-emmy-noether-and-symmetry-revisited/https://galileospendulum.org/wp-content/uploads/2011/10/u1_symmetry.pngCylindrical U(1) symmetryA featureless cylinder has a special axis of rotation running down the middle; rotation by any angle around this axis will be indistinguishable. However, if you leave the label on the soup can, the symmetry is broken. By Noether's theorem, this means the conservation law associated with U(1) symmetry will no longer hold.https://galileospendulum.org/wp-content/uploads/2011/10/so3_symmetry.pngSpherical SO(3) symmetryIf you rotate a featureless sphere by any angle around any axis running through the sphere's center, it will look exactly the same. This is known as spherical (or SO(3) for the math fans) symmetry.2012-03-02T13:15:14+00:00monthlyhttps://galileospendulum.org/2011/10/06/its-basic/2011-10-06T16:51:02+00:00monthlyhttps://galileospendulum.org/2011/10/05/quasilinks-for-quasicrystals-and-other-items/2011-10-05T21:23:14+00:00monthlyhttps://galileospendulum.org/2011/10/05/2011-nobel-prize-in-chemistry-discovery-of-quasicrystals/https://galileospendulum.org/wp-content/uploads/2011/10/icosohedron.pngicosohedronA 20-sided icosahedron: each side is an equilateral triangle.https://galileospendulum.org/wp-content/uploads/2011/10/hexagonal_lattice.pngA hexagonal latticeA hexagonal lattice, in which each atom (or molecule) is connected to its three nearest neighbors.https://galileospendulum.org/wp-content/uploads/2011/10/square_lattice.pngA square latticeA square lattice, where each atom (or molecule) is an equal distance from its four nearest neighbors. If you extend this into three dimensions, you get various types of cubic lattices. Note you can make the whole lattice by arranging tiles, each of which is a square.2012-01-22T08:51:19+00:00monthlyhttps://galileospendulum.org/2011/10/03/was-einstein-wrong-thats-the-wrong-question/https://galileospendulum.org/wp-content/uploads/2011/10/einstein-bohr.jpgEinstein and BohrEinstein and Bohr spent a lot of time discussing the nature of quantum mechanics and reality. Einstein ultimately rejected most of the implications of quantum mechanics, showing that it isn't just religious fundamentalists who have trouble accepting some scientific concepts.https://galileospendulum.org/wp-content/uploads/2011/10/pair_production.pngpair productionProduction of an electron-positron pair by a neutrino moving faster than the speed of light. Note the relative length of the arrow representing the neutrino's velocity before and after the pair production.2011-10-20T22:48:56+00:00monthlyhttps://galileospendulum.org/2011/10/02/wot-is-this-weekend-of-which-you-speak/https://galileospendulum.org/wp-content/uploads/2011/10/mercury_features.pngRaditladi impact basin on MercuryInteresting hollows in an impact basin on Mercury, which may have been caused by sublimation of material -- turning solids directly into gas.2011-10-02T13:23:12+00:00monthlyhttps://galileospendulum.org/2011/09/30/what-are-neutrinos-anyway/https://galileospendulum.org/wp-content/uploads/2011/09/p-p_chain.pnghydrogen fusionHow the Sun shines (first step): two protons get slammed together to create deuterium (which is hydrogen with a neutron added). Since the total amount of electric charge has to be preserved, the process creates a position (the antimatter partner to electrons). To conserve energy, momentum, and the like, an electron neutrino is also produced. The final piece is a gamma ray photon, which after a long period and a lot of collisions with atoms loses energy enough to become the visible light we get from the Sun. [Credit: moi]2011-09-30T18:41:12+00:00monthlyhttps://galileospendulum.org/2011/09/29/marching-on-our-nations-capital/2011-09-29T18:44:52+00:00monthlyhttps://galileospendulum.org/2011/09/28/let-there-be-100-carl-sagans/https://galileospendulum.org/wp-content/uploads/2011/09/sagan_snooki.jpgSagan vs. Snooki2011-10-02T02:34:21+00:00monthlyhttps://galileospendulum.org/2011/09/28/wednesday-morning-3-am/https://galileospendulum.org/wp-content/uploads/2011/09/sunspot-group-ar-1302.jpgsunspot group ar 1302Sunspot Group AR 13022011-09-28T13:15:27+00:00monthlyhttps://galileospendulum.org/2011/09/27/link-roundup-for-tuesday/https://galileospendulum.org/wp-content/uploads/2011/09/titan_rings_small.pngTitan, Saturn's largest moonSaturn's largest moon Titan, with Saturn's rings as the backdrop.2011-09-27T12:10:52+00:00monthlyhttps://galileospendulum.org/2011/09/26/sic-transit-gloria-fomalhaut/2011-09-26T16:14:16+00:00monthlyhttps://galileospendulum.org/2011/09/26/galileos-pendulum-has-a-new-look/2011-09-28T16:45:01+00:00monthlyhttps://galileospendulum.org/2011/09/25/decidedly-subluminal-sunday-morning-links/https://galileospendulum.org/wp-content/uploads/2011/09/get_fuzzy_ladder.pngpanel from "Get Fuzzy""Get Fuzzy" shows why superstition ain't the way.2011-09-25T19:50:59+00:00monthlyhttps://galileospendulum.org/2011/09/23/science-museums-are-for-everyone/https://galileospendulum.org/wp-content/uploads/2011/09/planetarium_main.jpgM.D. Anderson PlanetariumThe M.D. Anderson Planetarium, which I used to serve as director.2011-09-23T21:56:50+00:00monthlyhttps://galileospendulum.org/2011/09/23/i-dont-want-to-write-about-neutrinos/https://galileospendulum.org/wp-content/uploads/2011/09/opera_neutrino_apparatus.pngTiming in the OPERA neutrino measurementHow the timing was accomplished in the OPERA neutrino measurement. Graphic is borrowed from the original paper.https://galileospendulum.org/wp-content/uploads/2011/09/neutrinos_panel.pngpanel from xkcdAs usual, xkcd gets it right.2012-06-09T12:25:16+00:00monthlyhttps://galileospendulum.org/2011/09/22/the-patron-saint-of-public-science-outreach/https://galileospendulum.org/wp-content/uploads/2011/09/faraday.gifMichael FaradayMichael Faraday (1791-1867) was a chemist, physicist, and popularizer of science. He also sported truly excellent sideburns.2011-09-23T08:40:50+00:00monthlyhttps://galileospendulum.org/2011/09/22/are-any-of-us-natural-scientists/2011-10-04T18:49:59+00:00monthlyhttps://galileospendulum.org/2011/09/21/the-blogger-absconds/2011-09-21T13:32:34+00:00monthlyhttps://galileospendulum.org/2011/09/20/galactic-vagabonds/2011-09-21T00:54:31+00:00monthlyhttps://galileospendulum.org/2011/09/20/tuesday-linkses-my-precioussss/2011-09-20T19:47:56+00:00monthlyhttps://galileospendulum.org/2011/09/19/foucaults-pendulum-its-not-just-a-conspiracy-theory/https://galileospendulum.org/wp-content/uploads/2011/09/foucault_small.pngLeon FoucaultJean Bernard Léon Foucault, the physicist who figured out how to show Earth rotates on its axis using a special pendulum.2011-09-20T00:37:19+00:00monthlyhttps://galileospendulum.org/2011/09/19/monday-link-roundup/https://galileospendulum.org/wp-content/uploads/2011/09/rhea.jpgRheaSaturn's moon Rhea, as seen by the Cassini probe.2011-09-19T21:12:55+00:00monthlyhttps://galileospendulum.org/2011/09/18/storms-are-on-the-ocean/https://galileospendulum.org/wp-content/uploads/2011/09/neptune.pngNeptuneA different view of Neptune.2011-09-19T00:04:03+00:00monthlyhttps://galileospendulum.org/2011/09/17/saturday-morning-link-roundup/https://galileospendulum.org/wp-content/uploads/2011/09/vesta_south_pole.jpgVesta_south_poleThe view of Vesta's south pole, taken by the Dawn spacecraft.2011-09-17T13:47:24+00:00monthlyhttps://galileospendulum.org/2011/09/16/galileo-sells-out/2011-09-17T14:21:46+00:00monthlyhttps://galileospendulum.org/2011/09/16/galileos-pendulum-is-one-year-old/https://galileospendulum.org/wp-content/uploads/2011/09/copernicus_revolution.jpgCopernicus revolutionThe Earth has completed one revolution around the Sun since Galileo's Pendulum started.2011-09-21T01:53:00+00:00monthlyhttps://galileospendulum.org/2011/09/15/thursday-morning-link-roundup/https://galileospendulum.org/wp-content/uploads/2011/09/ngc3521_small.jpgNGC 3521Beautiful spiral galaxy NGC 3521; click on the picture for more information.2011-09-15T15:27:25+00:00monthlyhttps://galileospendulum.org/2011/09/14/sync-or-swim/https://galileospendulum.org/wp-content/uploads/2011/09/sync3.pngStrong interactionThis sequence of three shows the case where the interaction is strong between the "runners": they start off uncorrelated, but the attraction between them is strong, so they quickly group together in one bunch. They will stay clumped up as long as the interaction strength remains high.https://galileospendulum.org/wp-content/uploads/2011/09/sync2.pngCorrelated vs. uncorrelatedThe figures show a group of 6 runners as red dots on a circular track. The top sequence of three is the case where the runners are correlated: they stick together in a tight group the whole time. The bottom sequence of three is the case where the runners are uncorrelated: they start off together, but because they aren't linked, they get more spread out over time.https://galileospendulum.org/wp-content/uploads/2011/09/sync1.pngTwo runnersTwo runners (Oscar and Brenda) on a track. They start off together (top frame), but Brenda is a little faster, so she gets ahead (center frame). However, since they are friends and want to run together, she then slows down a bit while Oscar speeds up, so their phases coincide (bottom frame).2011-09-14T21:24:46+00:00monthlyhttps://galileospendulum.org/2011/09/13/busy-day-link-roundup/2011-09-13T20:02:25+00:00monthlyhttps://galileospendulum.org/2011/09/12/how-i-killed-pluto-and-why-it-had-it-coming/2011-09-13T21:33:26+00:00monthlyhttps://galileospendulum.org/2011/09/12/one-writers-tribute/https://galileospendulum.org/wp-content/uploads/2011/09/stephenjaygould.jpgStephen Jay Gould2011-09-12T14:47:36+00:00monthlyhttps://galileospendulum.org/2011/09/07/a-platypus-star/https://galileospendulum.org/wp-content/uploads/2011/09/popiii.jpgPopulation III starThe composition of the mysterious star announced last week. (Figure from Astronomy PIcture of the Day; click for more information.)2011-09-07T15:03:31+00:00monthlyhttps://galileospendulum.org/2011/09/05/im-every-scientist-but-not-really/2011-09-05T23:55:50+00:00monthlyhttps://galileospendulum.org/2011/09/02/some-further-notes-on-black-holes/https://galileospendulum.org/wp-content/uploads/2011/09/schwarzschild.pngSchwarzschild (non-rotating) black holeAnatomy of a Schwarzschild (non-rotating) black hole. The event horizon is spherical, whose radius is the Schwarzschild radius. Outside of this is the photon sphere, where photons can move around the black hole in perfectly circular (albeit unstable) orbits. Note the singularity is a single point (so I've drawn it too big!).2011-09-03T00:54:01+00:00monthlyhttps://galileospendulum.org/2011/09/02/what-we-know-about-black-holes/https://galileospendulum.org/wp-content/uploads/2011/09/black_hole.pngCross-section of a black holeThe "interior" of a black hole. The rotation of the black hole is revealed by how it distorts the shape of spacetime around it: a veritable whirlpool dragging matter and light that comes too close. In the region known as the ergosphere, this effect is so strong nothing can be at rest, no matter how much energy it has. Traveling closer (not that you'd want to), the event horizon defines the black hole's boundary. Once anything passes inside the event horizon, it cannot return to the outside universe. [Picture courtesy of me.]2011-09-15T01:23:04+00:00monthlyhttps://galileospendulum.org/2011/09/01/what-does-earthlike-mean/2011-09-01T14:46:35+00:00monthlyhttps://galileospendulum.org/2011/08/29/hurricanes-on-earth-hurricanes-on-jupiter/https://galileospendulum.org/wp-content/uploads/2011/08/coriolis1.pngCoriolis effectThe Coriolis force and its effect on projectiles (left side) and air flows (right side). Note that things are opposite in the southern hemisphere compared with the northern.https://galileospendulum.org/wp-content/uploads/2011/08/latitudes.pnglatitudesPoints at different latitudes on Earth will move at different speeds, since every point must rotate around the axis in 24 hours.https://galileospendulum.org/wp-content/uploads/2011/08/red_spot.pngcartoon of Great Red SpotA cartoon depiction of the Great Red Spot (adapted from Carroll & Ostlie's astrophysics textbook). Arrows indicate direction of atmospheric flow; note that the Red Spot sits at the boundary between bands moving in opposite directions.https://galileospendulum.org/wp-content/uploads/2011/08/coriolis.pngcoriolisSome cartoons to help understand the Coriolis force. The globe on the left has several latitude lines; like colors indicate equal latitudes, and therefore equal speed of rotation about the axis. The figure on the right is the effect of the Coriolis force, which is opposite for the northern and southern hemispheres.2011-08-29T17:47:34+00:00monthlyhttps://galileospendulum.org/2011/08/27/perspective/https://galileospendulum.org/wp-content/uploads/2011/08/jupiter.jpgJupiterJupiter again, showing the banded cloud structure and of course the Great Red Spot.2011-08-27T14:07:43+00:00monthlyhttps://galileospendulum.org/2011/08/26/its-a-diamond-planet-that-isnt-diamond-or-a-planet/https://galileospendulum.org/wp-content/uploads/2011/08/sirius-b.jpgsirius bThe white dwarf Sirius B is the small dot at the lower left of Sirius (the Dog Star). The "diamond planet" is probably also a white dwarf, albeit one with highly unusual properties.https://galileospendulum.org/wp-content/uploads/2011/08/diamond-lattice.gifdiamond latticeThe crystal structure of diamond. Each blue dot is a carbon atom; a full diamond would have many of these individual cubes joined together at the sides and edges.2011-09-19T02:21:05+00:00monthlyhttps://galileospendulum.org/2011/08/25/oh-be-a-fine-girl-kiss-me-less-tongue-yo/https://galileospendulum.org/wp-content/uploads/2011/08/orion.jpgOrionThe constellation Orion, with Rigel, Betelgeuse, and Mintaka labeled.2011-11-22T01:33:13+00:00monthlyhttps://galileospendulum.org/2011/08/24/what-is-a-planet/2011-09-13T01:05:59+00:00monthlyhttps://galileospendulum.org/2011/08/22/depth-perception-and-deep-space/https://galileospendulum.org/wp-content/uploads/2011/08/parallax.pngParallax illustratedParallax, astronomer-style. The pale blue dot is Earth at two different points in its orbit. All distances are shrunk down a lot for clarity -- real stars of course are a lot farther away, so the parallax will be that much smaller.https://galileospendulum.org/wp-content/uploads/2011/08/depth_perception_frame.pngframe from xkcdA poetic xkcd illustrating scale and parallax.2011-08-22T16:03:03+00:00monthlyhttps://galileospendulum.org/2011/08/19/learning-to-be-a-better-teacher-by-writing/https://galileospendulum.org/wp-content/uploads/2011/08/homer-jacket.pngHomer Simpson, adjunct professorHomer Simpson is not a good role model for teachers.2011-08-20T13:26:05+00:00monthlyhttps://galileospendulum.org/2011/08/18/from-pendulums-to-quantum-oscillators/https://galileospendulum.org/wp-content/uploads/2011/08/energy_levels.pngenergy levels for a quantum oscillatorThe allowed energy levels for a quantum oscillator, which are determined mathematically by the parabolic curve shown. Note the lowest energy level is the zero point energy mentioned in the text.https://galileospendulum.org/wp-content/uploads/2011/08/ammonia.pngammonia moleculeTwo equivalent positions for the nitrogen atom (labeled N) in an ammonia molecule. The hydrogen atoms (marked H) are in the same places in both images.2011-08-18T21:02:36+00:00monthlyhttps://galileospendulum.org/2011/08/17/centrifugal-forces-and-trojan-horses/https://galileospendulum.org/wp-content/uploads/2011/08/lagrange.pngLagrange pointsThe locations of the 5 Lagrange points in relation to a planet and the sun.https://galileospendulum.org/wp-content/uploads/2011/08/ellipse.pngEarth's orbitCartoon version of Earth's orbit around the Sun. The sizes are not to scale, and the real orbit is a lot closer to a circle than what is shown.https://galileospendulum.org/wp-content/uploads/2011/08/centrifugal.pngRelativity of forcesThe force acting on the rider of a Gravitron depends on your reference frame: the outsider sees a force from the wall, while the rider feels a centrifugal force pressing her against the wall.https://galileospendulum.org/wp-content/uploads/2011/07/centrifugal_force_panel.pngxkcd and the centrifugal forcePanel from xkcd -- click for the whole comic.2011-08-18T14:50:55+00:00monthlyhttps://galileospendulum.org/2011/08/16/a-useful-banner/https://galileospendulum.org/wp-content/uploads/2011/08/galileo-smackafool.jpgDoes Galileo have to smack a fool?Please do not use Galileo to support unscientific positions on climate change.2011-08-17T01:08:18+00:00monthlyhttps://galileospendulum.org/2011/08/04/my-scientists-brain-vs-my-scientists-heart/2011-08-05T00:02:23+00:00monthlyhttps://galileospendulum.org/2011/08/02/black-holes-dont-exist/https://galileospendulum.org/wp-content/uploads/2011/07/saga-small.jpgSagittarius A*Composite image of Sagittarius A*, including the orbits of several star (labeled SO-1, SO-2, etc.) close in.2013-01-03T04:18:02+00:00monthlyhttps://galileospendulum.org/2011/08/02/the-darkness-on-the-edge-of-the-galaxy/2011-08-02T09:34:06+00:00monthlyhttps://galileospendulum.org/2011/07/29/friday-metablogging-with-cats/https://galileospendulum.org/wp-content/uploads/2011/07/harriet-and-her-teddy-tube.jpgHarriet the Brave Little ToasterMy cat Harriet disapproves of incivility and crackpottery in the comments section. (Actually, she doesn't really care either way, but you find an illustration for a commenting policy page.)https://galileospendulum.org/wp-content/uploads/2011/07/pascal-footstool.jpgPascal the catPascal the cat, named for the French physicist-mathematician-philosopher.2011-07-29T13:30:17+00:00monthlyhttps://galileospendulum.org/2011/07/27/the-biggest-things-in-the-universe-transcript/https://galileospendulum.org/wp-content/uploads/2011/07/6dfgs.jpg6 degree field galaxy survey6 Degree Field galaxy survey (6dFGS) map of 125,071 galaxies in the nearby universe, showing how they are clustered together. [Credit: C. Fluke/6dF Survey]https://galileospendulum.org/wp-content/uploads/2011/07/betelgeuse.jpgBetelgeuseBetelgeuse is a supergiant star whose outer layers are significantly nonspherical -- gravity isn't strong enough to keep the star in a clean spherical shape.2011-07-27T12:29:44+00:00monthlyhttps://galileospendulum.org/2011/07/21/finding-mass-without-a-scale/https://galileospendulum.org/wp-content/uploads/2011/07/electron2.pngelectron orbit in a magnetic fieldhttps://galileospendulum.org/wp-content/uploads/2011/07/electron.pngelectron orbit in a magnetic fieldElectron orbit in a magnetic field. The orbit is circular -- we're seeing the setup from an angle for clarity, so that the magnet doesn't block our view.https://galileospendulum.org/wp-content/uploads/2011/07/kepler.pngKepler's third lawA simple orbit to illustrate Kepler's third lawhttps://galileospendulum.org/wp-content/uploads/2011/07/keplers-3rd-law.pngKeplers 3rd lawhttps://galileospendulum.org/wp-content/uploads/2011/07/johannes_kepler_1610.jpgJohannes KeplerJohannes Kepler (December 27, 1571- November 15, 1630) solved the major problems of the Copernican system with his three laws of planetary motion. He was also a great geometer, as indicated by his trapezoidal beard.https://galileospendulum.org/wp-content/uploads/2011/07/vesta_small.jpgVestaThe large asteroid Vesta, as photographed by the Dawn probe. Click for a much larger high-resolution version.2011-09-07T19:40:35+00:00monthlyhttps://galileospendulum.org/2011/07/21/boats-against-the-current-borne-back-ceaselessly-into-the-past/2011-07-21T12:42:33+00:00monthlyhttps://galileospendulum.org/2011/07/20/moons-do-not-a-planet-make/2011-07-21T00:12:23+00:00monthlyhttps://galileospendulum.org/2011/07/15/does-cancer-cause-cell-phones/2011-07-15T12:38:05+00:00monthlyhttps://galileospendulum.org/2011/07/14/seeing-through-gravitys-lens-transcript/https://galileospendulum.org/wp-content/uploads/2011/07/lensing.pngHow Lensing WorksGravity shapes the geometry of spacetime. Light follows the straightest possible path as dictated by the geometry.2011-07-14T12:51:43+00:00monthlyhttps://galileospendulum.org/2011/07/11/neptune-the-mystic/https://galileospendulum.org/wp-content/uploads/2011/07/neptune.jpgNeptuneThe real reason to post this picture is just because I like Neptune. [Credit: NASA]2011-07-12T12:38:17+00:00monthlyhttps://galileospendulum.org/2011/07/08/age-of-miracles/2011-07-08T13:16:34+00:00monthlyhttps://galileospendulum.org/2011/07/07/space-exploration-is-not-over/https://galileospendulum.org/wp-content/uploads/2011/07/voyager_2_jupiter_io.jpgJupiter with its moon Io, as seen by the Voyager 2 missionJupiter with its moon Io, as seen by the Voyager 2 mission.2011-07-07T19:42:34+00:00monthlyhttps://galileospendulum.org/2011/06/29/black-holes-dont-suck/https://galileospendulum.org/wp-content/uploads/2011/06/black_holes.pngSimplified representation of trajectories near a black holeSimplified representation of trajectories near a black hole.https://galileospendulum.org/wp-content/uploads/2011/06/butthead.pngBlack holes don't suck2011-06-29T13:13:34+00:00monthlyhttps://galileospendulum.org/2011/06/24/physics-quanta-from-identical-twins-to-voltron-physics-style/https://galileospendulum.org/wp-content/uploads/2011/06/feynman_diagram_of_electron-positron_annihilation_v2.pngFeynman diagram for electron-positron annihilationA Feynman diagram for electron-positron annihilation. Note that the positron is shown moving backwards in time.https://galileospendulum.org/wp-content/uploads/2011/06/feynman.jpgRichard FeynmanRichard Feynman (1918-1988)2011-06-24T16:00:41+00:00monthlyhttps://galileospendulum.org/2011/06/20/the-dance-of-helene/https://galileospendulum.org/wp-content/uploads/2011/06/tethys.jpgTethysSaturn's moon Tethys, which helps provide a gravitational point for Helene2011-06-20T23:54:56+00:00monthlyhttps://galileospendulum.org/2011/06/16/history-is-a-nightmare-from-which-i-am-trying-to-awake/2011-06-16T19:54:43+00:00monthlyhttps://galileospendulum.org/2011/06/13/the-biggest-things-in-the-universe/https://galileospendulum.org/wp-content/uploads/2011/06/coma_hst.jpgThe Coma ClusterThe Coma Cluster, which Fritz Zwicky used to argue that much of the mass of the universe is invisible.https://galileospendulum.org/wp-content/uploads/2011/06/virgocluster-in-xrays.jpgVirgo Cluster in X-raysVirgo Cluster in X-rays. Note that the galaxies do show up (mostly because of the giant black hole in the nucleus of each), but they aren't nearly as bright as the gas.https://galileospendulum.org/wp-content/uploads/2011/06/m86.jpgThe center of the Virgo clusterThe center of the Virgo clusterhttps://galileospendulum.org/wp-content/uploads/2011/06/m87.jpgElliptical galaxy M87Elliptical galaxy M87https://galileospendulum.org/wp-content/uploads/2011/06/m51center_hst1.jpgSpiral galaxy M51M51, a spiral galaxy. While it isn't identical to the Milky Way, it shares many characteristics.2011-06-13T12:43:42+00:00monthlyhttps://galileospendulum.org/2011/06/12/everything-you-wanted-to-know-about-physics-but-were-afraid-to-ask/2011-06-12T17:18:01+00:00monthlyhttps://galileospendulum.org/2011/05/31/physics-quanta-pendulums-revisited/https://galileospendulum.org/wp-content/uploads/2011/05/pendulum_underdamped.pngPendulum with air resistanceThe starting positions and velocities are exactly the same as in the previous plot, but this time air resistance is includedhttps://galileospendulum.org/wp-content/uploads/2011/05/pendulum_no_damping.pngPendulum phase diagram (no air resistance)Velocity and position can be plotted on the same axes, but they aren't really perpendicular quantities. (See my earlier post for a complete explanation of this figure.)https://galileospendulum.org/wp-content/uploads/2011/05/big_swing.pngPendulum swinging through a large angleIf the bob is attached with a wire instead of a string, there is a second equilibrium position at the top of the swing2011-06-12T05:36:18+00:00monthlyhttps://galileospendulum.org/2011/06/11/one-of-those-weeks/2011-06-11T20:35:19+00:00monthlyhttps://galileospendulum.org/2011/06/08/a-warm-welcome-to-you-all/2011-06-08T16:07:27+00:00monthlyhttps://galileospendulum.org/2011/06/07/guest-post-at-scientific-american/https://galileospendulum.org/wp-content/uploads/2011/06/simulated_2-slit_experiment.jpgSimulated double-slit experiment resultsOh, you think I'm going to explain this figure here? You have to read the actual post!2011-06-07T18:40:15+00:00monthlyhttps://galileospendulum.org/2011/06/05/explosions-in-the-sky/2011-06-07T14:04:08+00:00monthlyhttps://galileospendulum.org/2011/06/04/the-immortal-life-of-henrietta-lacks/2011-06-05T01:16:02+00:00monthlyhttps://galileospendulum.org/2011/06/03/curiosity-and-ownership-of-science/2011-06-03T22:53:20+00:00monthlyhttps://galileospendulum.org/2011/05/31/do-cell-phones-cause-cancer/2011-05-31T21:34:40+00:00monthlyhttps://galileospendulum.org/2011/05/28/yes-lisa-daddys-a-teacher/2011-05-28T21:17:50+00:00monthlyhttps://galileospendulum.org/2011/05/27/written-in-stone/https://galileospendulum.org/wp-content/uploads/2011/05/written-in-stone-lol.jpg"Written in Stone" by Brian SwitekPascal the cat is only interested in the evolution of birds.https://galileospendulum.org/wp-content/uploads/2011/05/written-in-stone1.jpg"Written in Stone" by Brian SwitekDid Tyrannosaurus taste like chicken?2011-05-27T15:14:41+00:00monthlyhttps://galileospendulum.org/2011/05/27/they-got-charles-darwin-trapped-out-there-on-highway-five/2011-05-27T12:33:57+00:00monthlyhttps://galileospendulum.org/2011/05/25/may-we-all-show-such-spirit/https://galileospendulum.org/wp-content/uploads/2011/05/spirit.jpgSpirit Mars rover (artist's depiction)2011-05-25T20:37:29+00:00monthlyhttps://galileospendulum.org/2011/05/24/physics-quanta-the-pendulums-swing/https://galileospendulum.org/wp-content/uploads/2011/05/long_string.pngTwo pendulums with different string lengthsA longer string will have a larger period of oscillationhttps://galileospendulum.org/wp-content/uploads/2011/05/basic_pendulum2.pngbasic pendulumhttps://galileospendulum.org/wp-content/uploads/2011/05/basic_pendulum.pngBasic pendulum2011-05-24T21:38:15+00:00monthlyhttps://galileospendulum.org/2011/05/23/is-there-anybody-out-there/https://galileospendulum.org/wp-content/uploads/2011/05/seti-allen-array.jpgSETI Allen Telescope ArrayAllen Telescope Array, searching for intelligent extraterrestrial life2011-05-23T21:39:00+00:00monthlyhttps://galileospendulum.org/2011/05/21/what-if-they-held-an-apocalypse-but-nobody-came/2011-05-21T23:51:54+00:00monthlyhttps://galileospendulum.org/2011/05/19/revisiting-schrodingers-cat/https://galileospendulum.org/wp-content/uploads/2011/05/laser-eyes.jpgPut me in that box at your own risk!Put me in that box at your own risk!2012-08-15T19:52:18+00:00monthlyhttps://galileospendulum.org/2011/05/18/the-finals-countdown/2011-05-18T22:05:48+00:00monthlyhttps://galileospendulum.org/2011/05/15/fundamentalist-numerology-at-least-i-didnt-quote-r-e-m-lyrics/https://galileospendulum.org/wp-content/uploads/2011/05/seven.pngseven2011-05-19T20:28:27+00:00monthlyhttps://galileospendulum.org/2011/05/14/dignity/https://galileospendulum.org/wp-content/uploads/2011/05/terror.jpgterror2011-05-14T23:51:20+00:00monthlyhttps://galileospendulum.org/2011/05/12/all-good-things-reach-their-end/2011-05-13T23:50:14+00:00monthlyhttps://galileospendulum.org/2011/05/09/better-than-the-best/https://galileospendulum.org/wp-content/uploads/2011/05/marie_curie.jpgMarie Curie2011-05-09T22:10:08+00:00monthlyhttps://galileospendulum.org/2011/05/09/zombie-marie-curie-and-the-problem-of-tokenism/https://galileospendulum.org/wp-content/uploads/2011/05/marie_curie_panel.pngPanel from xkcd2011-05-09T12:20:42+00:00monthlyhttps://galileospendulum.org/2011/05/07/a-gathering-of-great-minds/https://galileospendulum.org/wp-content/uploads/2011/05/1927-solvay-conference-small.jpg1927 Solvay ConferenceIt's like "Where's Waldo?", only the game is "Where's Curie?"2011-05-07T17:48:22+00:00monthlyhttps://galileospendulum.org/2011/05/04/pendulum-waves-and-the-beginnings-of-quantum-physics/2013-09-19T23:42:11+00:00monthlyhttps://galileospendulum.org/2011/04/30/saturday-open-thread-whats-your-favorite-book-on-evolution/2012-02-09T11:44:33+00:00monthlyhttps://galileospendulum.org/2011/04/30/how-do-you-teach-your-cats-about-evolution/https://galileospendulum.org/wp-content/uploads/2011/04/pascal_lol.jpgPascal the cat discovers Neil Shubin's book "Your Inner Fish"My favorite image from my blog for this year: my cat Pascal discovers "Your Inner Fish" by Neil Shubin.2011-04-30T16:06:06+00:00monthlyhttps://galileospendulum.org/2011/04/28/alan-alda-science-is-emotional/2011-04-28T22:10:25+00:00monthlyhttps://galileospendulum.org/2011/04/27/on-what-authority/https://galileospendulum.org/wp-content/uploads/2011/04/thagomizer.jpgThagomizerA stegosaur's authority rested in its thagomizer2011-04-27T20:36:28+00:00monthlyhttps://galileospendulum.org/2011/04/25/i-think-this-counts-as-a-good-excuse/2011-04-26T01:59:33+00:00monthlyhttps://galileospendulum.org/2011/04/23/dc-science-writers-association-conference/2011-04-24T00:28:15+00:00monthlyhttps://galileospendulum.org/2011/04/22/is-there-life-in-the-universe/https://galileospendulum.org/wp-content/uploads/2011/04/earthrise_apollo8.gifEarth, taken from orbit by Apollo 8 astronautsImage taken from Moon orbit by the Apollo 8 astronauts. [Credit: NASA]2011-04-24T00:06:32+00:00monthlyhttps://galileospendulum.org/2011/04/22/seeing-through-gravitys-lens/https://galileospendulum.org/wp-content/uploads/2011/04/planet_microlensing.jpgMicrolensing light curve to find an exoplanethttps://galileospendulum.org/wp-content/uploads/2011/04/ring-lens.jpgring lensYo momma's so fat, she constitutes a strong gravitational lens.https://galileospendulum.org/wp-content/uploads/2011/04/bullet_cluster.jpgthe Bullet Cluster - two galaxy clusters collidingThe Bullet Cluster is a galaxy cluster in the process of merging. The pink regions are the hot gas as imaged using X-rays; the blue is the dark matter as found using gravitational lensing. [Credits: X-ray: NASA/CXC/CfA/ M.Markevitch et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/ D.Clowe et al. Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al.]https://galileospendulum.org/wp-content/uploads/2011/04/18_einstein_cross.jpgEinstein Cross gravitational lens from Hubble2011-04-22T14:27:45+00:00monthlyhttps://galileospendulum.org/2011/04/20/the-mystery-of-the-apocryphal-einstein-quote-solved/https://galileospendulum.org/wp-content/uploads/2011/04/bacon-francis1.jpgSir Francis Bacon2011-08-02T07:01:49+00:00monthlyhttps://galileospendulum.org/2011/04/19/friday-podcast/https://galileospendulum.org/wp-content/uploads/2011/04/365-days-logo2.png365-days-logo22011-04-19T18:29:32+00:00monthlyhttps://galileospendulum.org/2011/04/18/matter-energy-and-pseudoscience/https://galileospendulum.org/wp-content/uploads/2011/04/suspension_panel.jpgsuspension_panel2011-04-19T01:51:32+00:00monthlyhttps://galileospendulum.org/2011/04/15/big-trouble-on-little-mimas/https://galileospendulum.org/wp-content/uploads/2011/04/mimas_circle_overlay.pngMimas with a circle overlaid to show non-spherical characterMimas is significantly nonspherical (prolate, for the math buffs). To show this, I overlaid a red circle on top of the moon. Note that the elongation is along the axis perpendicular to the Herschel crater (the flat-looking feature at the top of the image).https://galileospendulum.org/wp-content/uploads/2011/04/mimas_small.pngMimas "side view"https://galileospendulum.org/wp-content/uploads/2011/04/mimas_cassini.jpgMimas "front view"2011-04-16T12:35:39+00:00monthlyhttps://galileospendulum.org/2011/04/14/saturns-ears/https://galileospendulum.org/wp-content/uploads/2011/04/ring_waves_small.pngDensity waves in Saturn's rings2011-04-15T00:58:35+00:00monthlyhttps://galileospendulum.org/2011/04/11/in-honor-of-yuri-gagarin/https://galileospendulum.org/wp-content/uploads/2011/04/gagarin_in_sweden.jpgYuri Alekseyevich Gagarin2011-04-11T23:17:43+00:00monthlyhttps://galileospendulum.org/2011/04/11/a-little-knowledge-is-a-dangerous-thing/https://galileospendulum.org/wp-content/uploads/2011/04/gravity.jpggravity - just a theory2011-04-11T22:15:47+00:00monthlyhttps://galileospendulum.org/2011/04/10/does-fear-make-creationism-or-intelligent-design-seem-more-attractive/https://galileospendulum.org/wp-content/uploads/2011/04/death-discworld.jpgDeath from Discworld (art by Paul Kidby)2011-04-11T00:51:58+00:00monthlyhttps://galileospendulum.org/2011/04/08/invoking-einstein-to-defend-teaching-creationism/2011-04-08T22:05:08+00:00monthlyhttps://galileospendulum.org/2011/04/08/blind-spots-and-male-privilege/https://galileospendulum.org/wp-content/uploads/2011/04/patriarchy_panel.pngPanel from "Cat and Girl"2011-04-08T15:55:25+00:00monthlyhttps://galileospendulum.org/2011/04/06/jelly-beans-and-science-reporting/https://galileospendulum.org/wp-content/uploads/2011/04/significant_panel.pngPanel from xkcd2011-04-07T01:29:13+00:00monthlyhttps://galileospendulum.org/2011/04/05/writers-block/https://galileospendulum.org/wp-content/uploads/2011/04/empty-speech-bubble.jpgempty-speech-bubble2011-04-05T22:32:49+00:00monthlyhttps://galileospendulum.org/2011/04/03/the-importance-of-being-earnest-about-encouraging-girls-in-science/2011-04-05T22:42:13+00:00monthlyhttps://galileospendulum.org/2011/04/02/anomaly-schnomaly/2011-04-02T21:45:25+00:00monthlyhttps://galileospendulum.org/2011/04/01/friday-fun-link-roundup/2011-04-01T15:30:36+00:00monthlyhttps://galileospendulum.org/2011/03/31/the-aharonov-bohm-effect-or-how-is-a-coffee-cup-like-a-donut/https://galileospendulum.org/wp-content/uploads/2011/03/aharonov_bohm.pngAharonov Bohm setuphttps://galileospendulum.org/wp-content/uploads/2011/03/mug_and_torus_morph.gifTorus and coffee cup deforming into each otherA coffee mug and a donut (torus) are topologically equivalent shapes: they both contain a single hole, and so can be deformed into each other without removing the hole or tearing a new one.2011-04-01T11:56:23+00:00monthlyhttps://galileospendulum.org/2011/03/29/exoplanet-transit-authority/https://galileospendulum.org/wp-content/uploads/2011/03/transit1.pngDiagram of an exoplanet transit eventhttps://galileospendulum.org/wp-content/uploads/2011/03/transit_small.pngDiagram of an exoplanet transit eventhttps://galileospendulum.org/wp-content/uploads/2011/03/keplersunsplanets_small.jpgKeplerSunsPlanets_small2011-03-29T23:09:19+00:00monthlyhttps://galileospendulum.org/2011/03/28/the-problem-of-string-theory/2012-06-20T02:28:48+00:00monthlyhttps://galileospendulum.org/2011/03/27/the-time-has-come/https://galileospendulum.org/wp-content/uploads/2011/03/galileo.jpgGalileoGalileo is not amused by the use of his name and image to promote pseudoscience.2011-03-27T20:15:27+00:00monthlyhttps://galileospendulum.org/2011/03/25/is-intelligent-design-agnostic/2011-03-27T21:11:11+00:00monthlyhttps://galileospendulum.org/2011/03/26/a-spacesuit-ballet/2011-03-26T13:14:48+00:00monthlyhttps://galileospendulum.org/2011/03/25/friday-fun/2011-03-25T15:19:56+00:00monthlyhttps://galileospendulum.org/2011/03/24/happy-birthday-harry-houdini/https://galileospendulum.org/wp-content/uploads/2011/03/houdini.jpgHarry Houdini2011-03-24T17:34:10+00:00monthlyhttps://galileospendulum.org/2011/03/24/creationism-apocalypse-now/2011-03-24T13:07:10+00:00monthlyhttps://galileospendulum.org/2011/03/23/the-desert-of-the-real/2011-03-23T18:21:08+00:00monthlyhttps://galileospendulum.org/2011/03/22/galaxy-clusters-are-hot/https://galileospendulum.org/wp-content/uploads/2011/03/coma_xray.jpgcoma_xray2011-03-22T16:14:42+00:00monthlyhttps://galileospendulum.org/2011/03/21/big-changes-are-afoot/2011-03-21T16:20:08+00:00monthlyhttps://galileospendulum.org/2011/03/20/equinox/2011-03-20T21:01:48+00:00monthlyhttps://galileospendulum.org/2011/03/20/part-3-in-a-diverging-series/https://galileospendulum.org/wp-content/uploads/2011/03/new_age_quantum_panel.pngPanel from Saturday Morning Breakfast Cereal2011-03-20T11:11:56+00:00monthlyhttps://galileospendulum.org/2011/03/19/final-thoughts-on-the-supermoon-nonsense/2011-03-20T08:59:57+00:00monthlyhttps://galileospendulum.org/2011/03/18/the-smallest-planet-has-a-new-satellite/https://galileospendulum.org/wp-content/uploads/2011/03/mercury_low_res.pngMercury, from MESSENGER2011-03-18T18:30:53+00:00monthlyhttps://galileospendulum.org/2011/03/18/ive-got-soul-and-im-supermoon/2011-03-18T15:36:35+00:00monthlyhttps://galileospendulum.org/2011/03/17/its-not-easy-being-green/https://galileospendulum.org/wp-content/uploads/2011/03/blackbody.pngthermal spectrumThermal spectra for four different objects, whose temperatures are fairly typical for stars. Our Sun is most like the curve in green.2013-04-16T20:33:24+00:00monthlyhttps://galileospendulum.org/2011/02/05/dont-understand-something-blame-it-on-quantum-mechanics/https://galileospendulum.org/wp-content/uploads/2011/02/schrodingers-lolcat.jpgShroedinger's LOLcat2011-03-17T01:00:50+00:00monthlyhttps://galileospendulum.org/2011/03/14/happy-birthday-albert-einstein/https://galileospendulum.org/wp-content/uploads/2011/03/einstein.jpgeinstein2011-03-14T17:53:04+00:00monthlyhttps://galileospendulum.org/2011/03/13/light-postings/2011-03-13T16:24:28+00:00monthlyhttps://galileospendulum.org/2011/03/11/there-is-no-such-thing-as-a-supermoon/2011-03-14T13:02:13+00:00monthlyhttps://galileospendulum.org/2011/03/10/musical-pi/2011-03-10T14:12:07+00:00monthlyhttps://galileospendulum.org/2011/03/08/on-symmetry-and-emmy-noether/https://galileospendulum.org/wp-content/uploads/2011/03/noether.jpgEmmy Noether2011-03-08T18:01:39+00:00monthlyhttps://galileospendulum.org/2011/03/08/you-can-go-about-your-business-move-along/2011-03-08T08:45:08+00:00monthlyhttps://galileospendulum.org/2011/03/07/bacteria-from-outer-space/2011-03-07T00:05:37+00:00monthlyhttps://galileospendulum.org/2011/03/06/warning-self-indulgence-ahead/https://galileospendulum.org/wp-content/uploads/2011/03/einstein-bohr.jpgEinstein and Bohr2011-03-06T21:52:36+00:00monthlyhttps://galileospendulum.org/2011/03/06/the-quantum-of-laziness/https://galileospendulum.org/wp-content/uploads/2011/03/quantum-laziness-panel.pngquantum laziness2011-03-06T13:14:36+00:00monthlyhttps://galileospendulum.org/2011/03/05/is-beauty-truth/2011-03-05T15:46:53+00:00monthlyhttps://galileospendulum.org/2011/03/04/cosmic-meaning-vs-personal-meaning/https://galileospendulum.org/wp-content/uploads/2011/03/cosmic-speck-panel.pngwhy astronomer parents are bad2011-03-04T21:44:30+00:00monthlyhttps://galileospendulum.org/2011/03/04/a-few-quick-items/2011-03-04T19:18:24+00:00monthlyhttps://galileospendulum.org/2011/03/03/if-i-were-truly-a-fraud/https://galileospendulum.org/wp-content/uploads/2011/03/wizard_of_oz.jpgFrank Morgan from Wizard of Oz2011-03-03T13:00:16+00:00monthlyhttps://galileospendulum.org/2011/03/02/the-creationists-trilemma/2011-03-02T17:51:15+00:00monthlyhttps://galileospendulum.org/2011/03/01/i-have-told-a-lie/https://galileospendulum.org/wp-content/uploads/2011/03/beliefs_panel.jpgPanel from xkcd2011-03-02T15:44:48+00:00monthlyhttps://galileospendulum.org/2011/03/01/its-not-bold-to-be-a-creationist/2011-03-01T00:56:57+00:00monthlyhttps://galileospendulum.org/2011/02/28/teach-the-controversy-about-dark-matter/https://galileospendulum.org/wp-content/uploads/2011/02/bullet_cluster.jpgThe Bullet Cluster: two galaxy clusters colliding2011-09-07T15:25:29+00:00monthlyhttps://galileospendulum.org/2011/02/25/let-us-now-praise-famous-robots/https://galileospendulum.org/wp-content/uploads/2011/02/cassini-saturn.jpgCassini space probe (artist's conception)2011-02-25T21:27:36+00:00monthlyhttps://galileospendulum.org/2011/02/25/the-end-of-an-era/https://galileospendulum.org/wp-content/uploads/2011/02/space-shuttle-atlantis.jpgspace shuttle Atlantis2011-02-25T01:42:26+00:00monthlyhttps://galileospendulum.org/2011/02/22/historical-vs-logical-order/https://galileospendulum.org/wp-content/uploads/2011/02/xraybequerel.jpgX-rays: where do they come from?2011-02-22T23:57:54+00:00monthlyhttps://galileospendulum.org/2011/02/21/musicians-understand/2011-02-21T01:49:09+00:00monthlyhttps://galileospendulum.org/2011/02/20/tolerance-and-intolerance/2011-02-20T17:07:20+00:00monthlyhttps://galileospendulum.org/2011/02/19/happy-birthday-pluto-youre-still-not-a-planet-though/2011-02-21T06:54:04+00:00monthlyhttps://galileospendulum.org/2011/02/18/why-teach-general-relativity/https://galileospendulum.org/wp-content/uploads/2011/02/abell2218.jpgAbell 2218 gravitational lens2011-02-18T22:28:58+00:00monthlyhttps://galileospendulum.org/2011/02/17/the-arrogance-of-physicists/2011-02-17T19:39:08+00:00monthlyhttps://galileospendulum.org/2011/02/16/the-blogger-is-out/https://galileospendulum.org/wp-content/uploads/2011/02/out-to-lunch.jpgOut to Lunch - Eric Dolphy2011-02-16T21:11:32+00:00monthlyhttps://galileospendulum.org/2011/02/15/the-universe-loves-you/https://galileospendulum.org/wp-content/uploads/2011/02/valentine-sagan-small.gifI'm Sagan All My Love For You[Credit: Ironic Sans]2011-02-15T00:44:35+00:00monthlyhttps://galileospendulum.org/2011/02/14/first-they-came-for-the-evolutionary-biologists/https://galileospendulum.org/wp-content/uploads/2011/02/cmb_timeline150.jpgCMB_Timeline1502011-02-19T12:13:15+00:00monthlyhttps://galileospendulum.org/2011/02/13/mister-charles-darwin-had-the-gall-to-ask/2011-02-13T12:32:35+00:00monthlyhttps://galileospendulum.org/2011/02/12/happy-birthday-charles-darwin/https://galileospendulum.org/wp-content/uploads/2011/02/charles_darwin.jpgCharles Darwin2011-02-12T14:23:49+00:00monthlyhttps://galileospendulum.org/2011/02/10/dinosaurs-have-gotten-so-much-cooler/2011-02-20T09:12:27+00:00monthlyhttps://galileospendulum.org/2011/02/08/albert-einstein-was-a-ladies-man/2011-02-08T21:51:06+00:00monthlyhttps://galileospendulum.org/2011/02/08/light-posting/2011-02-08T00:50:38+00:00monthlyhttps://galileospendulum.org/2011/02/04/in-which-the-blog-writer-asks-questions/https://galileospendulum.org/wp-content/uploads/2011/02/question_box1.pngMario Bros. Bonus Box -- ka-ching!https://galileospendulum.org/wp-content/uploads/2011/02/question_box.pngquestion_box2011-02-06T13:16:31+00:00monthlyhttps://galileospendulum.org/2011/02/04/when-i-fight-authority/2011-02-04T19:35:25+00:00monthlyhttps://galileospendulum.org/2011/02/02/happy-groundhog-day/https://galileospendulum.org/wp-content/uploads/2011/02/woodchuck_2.jpegGroundhogs2011-02-10T19:52:37+00:00monthlyhttps://galileospendulum.org/2011/02/02/my-response/https://galileospendulum.org/wp-content/uploads/2011/02/enceladus.jpgEnceladusSaturn's moon Enceladushttps://galileospendulum.org/wp-content/uploads/2011/02/fomalhaut.jpgFomalhautFomalhaut with its ring of gas and a possible, but now heavily disputed, planet candidate.2011-02-12T10:06:37+00:00monthlyhttps://galileospendulum.org/2011/02/01/a-letter-from-a-third-grader/https://galileospendulum.org/wp-content/uploads/2011/02/voyager.jpgVoyager 2The Voyager 2 probe, which helped inspired me to go into science. No hard feelings, I hope.2011-02-01T15:52:25+00:00monthlyhttps://galileospendulum.org/2011/01/28/the-challenger/https://galileospendulum.org/wp-content/uploads/2011/01/challenger.jpgThe crew of the Challenger2011-01-28T14:30:11+00:00monthlyhttps://galileospendulum.org/2011/01/27/blog-business/2011-01-27T22:47:39+00:00monthlyhttps://galileospendulum.org/2011/01/26/101-uses-for-a-dead-scientist/2011-01-27T00:25:43+00:00monthlyhttps://galileospendulum.org/2011/01/24/does-anybody-really-know-what-time-it-is/2011-01-24T21:07:02+00:00monthlyhttps://galileospendulum.org/2011/01/20/the-zodiac-shuffle-according-to-astronomers/2011-01-20T23:07:57+00:00monthlyhttps://galileospendulum.org/2011/01/20/packing-for-mars/2011-01-20T15:23:15+00:00monthlyhttps://galileospendulum.org/2011/01/19/the-problem-of-evolutionary-psychology/2011-01-19T20:40:13+00:00monthlyhttps://galileospendulum.org/2011/01/13/your-astrological-sign-may-be-wrong/2011-02-06T18:12:20+00:00monthlyhttps://galileospendulum.org/2011/01/12/the-language-god-talks/2011-01-12T20:58:00+00:00monthlyhttps://galileospendulum.org/2010/11/07/scientific-literacy-part-1/2010-11-11T20:35:57+00:00monthlyhttps://galileospendulum.org/2010/10/21/95/https://galileospendulum.org/wp-content/uploads/2010/10/the_economic_argument.pngthe_economic_argument2013-08-19T04:09:33+00:00monthlyhttps://galileospendulum.org/2010/10/23/happy-birthday-planet-earth/2010-10-24T11:16:28+00:00monthlyhttps://galileospendulum.org/2010/10/20/ouija-and-communication-with-the-living/2010-10-20T23:14:41+00:00monthlyhttps://galileospendulum.org/2010/10/17/g-g-ghost-how-would-science-students-react-to-a-ghost/https://galileospendulum.org/wp-content/uploads/2010/10/ghost.jpgGhost2010-10-17T14:54:10+00:00monthlyhttps://galileospendulum.org/2010/10/02/the-goldilocks-planet/2010-10-13T20:44:28+00:00monthlyhttps://galileospendulum.org/2010/10/01/the-marvel-of-real-science/2010-10-05T12:57:45+00:00monthlyhttps://galileospendulum.org/2010/09/30/navigating-by-the-stars/2010-09-30T14:07:38+00:00monthlyhttps://galileospendulum.org/2010/09/26/%e2%80%9cturns-skeptics-into%c2%a0believers%e2%80%9d/2010-09-26T23:21:24+00:00monthlyhttps://galileospendulum.org/2010/09/17/just-a-few-quick-notes/2010-09-17T12:10:50+00:00monthlyhttps://galileospendulum.org/2010/09/16/galileo-was-wrong-and-we-all-know-it-somehow/https://galileospendulum.org/wp-content/uploads/2010/09/teach_geocentrism.jpgteach_geocentrismTeach the Controversy (Geocentrism)2010-09-17T12:42:18+00:00monthlyhttps://galileospendulum.org/2010/09/16/hello-world/2010-09-16T19:21:55+00:00monthlyhttps://galileospendulum.orgdaily1.02025-06-05T12:24:32+00:00