My heart leaps up when I behold
A rainbow in the sky:
So was it when my life began;
So is it now I am a man;
So be it when I shall grow old,
Or let me die!
The Child is father of the Man;
I could wish my days to be
Bound each to each by natural piety.
–William Wordsworth (1802)
Phil Plait (the Bad Astronomer) wrote a lovely piece for Slate, telling the story of how he knew he wanted to become a scientist. Nicole Gugliucci (the Noisy Astronomer) prompted him to call for everyone’s stories: their Moments of Science, where science first began to connect for them. Alas, I don’t have a nickname like they do (the Fuzzy Astronomer? the Bowler-Hatted Astronomer?), but I do have my own Moment of Science stories.
In fact, I have two stories: one from my childhood, the second from adulthood. As the
Al Kooper Wordsworth poem above states, the child is father of the man—meaning of course that who we were shapes who we are. There is another meaning relevant to me: the day we stop learning, we might as well go to our graves. Share your own stories in the comments, over at Bad Astronomy, or on Twitter using the hashtag #MomentOfScience .
The Child’s Story
The first real awareness I remember of science came when I was young, and the Voyager probes were exploring the outer Solar System. My brother had the Voyager 1 photo of Saturn (taken in 1980) on his wall from National Geographic, and I recall my father explaining what it represented. The very idea of worlds other than Earth is strange to a young child, so I don’t think I fully understood what he was saying at the time.
However, when I looked at the Voyager 2 images of Jupiter and its moons, I began to understand: these are different worlds, each with its own characteristics. Io and Europa and Jupiter, the giant planet itself—these imprinted themselves on my mind. I can still remember looking at the photos, flipping through the same few pages of National Geographic over and over again. Voyager 2 wasn’t the first or last probe to visit Jupiter, of course, but it was a brilliantly designed mission—and it captured my imagination. At that point in my life, I realized it was possible to be a scientist, and that studying science could provide beauty, wonder, and excitement. Anyone who thinks science is a dead, soulless field should try recapturing the moment of joy, the realization of whole other worlds to discover.
The Man’s Story
Fast-forward nearly two decades (with the requisite montage sequence), when I was finishing college and looking for a graduate school in physics. I visited a number of possible places to do a Ph.D., and toured many labs. (Even though I wanted to do theory, and my research is all theoretical, they always include the labs on a tour, which is a very good idea.) One lab turned out to be a major center of research using scanning tunneling electron microscopes (STMs), which use electrons to map the distribution of electric charge on the surface of materials to extremely high resolution.
The professor who showed me the lab, Michael Crommie, was visibly excited about the work he was doing. He brought out a number of their recent micrographs, including a few similar to the one at right. As he explained, they were trying to capture the behavior of electrons on the surface of the material—and here he provided me with a second Moment of Science. He said, “Those ripples are electron waves.”
Of course I had seen electron micrographs before, and probably had even read about some of Crommie’s work. However, the conversation in that lab provided the swich from a vague “knowing” to a full understanding and awareness of the implications. When you learn quantum mechanics, you know electrons are wavelike as well as particle-like, but you’re always taught that the wave character is hidden. Normal detectors show particles, not waves—but in the STM image, the wave character stands out. We aren’t seeing individual electrons, but their collective behavior; in a material, the interactions merge the distinct particles into a fluid with its own properties, and that’s what we see here. Yes, that’s what we are seeing: something that no light will ever show us, our eyes cannot see, but is nevertheless real and exists—and can be studied. This is the stuff we’re made of.
This story stands out in my memory, but it’s one of many moments of science. I hope it won’t be the last. The child is father of the man. So be it when I shall grow old, or let me die.
3 responses to “A Moment of Science”
[…] are dusty and diffuse, a fuzzy thin line on either side of Jupiter’s circular arcs. While Jupiter seen in sunlight is a colorful planet, this picture contains only simple contrasts: darkness, […]
[…] I’ve written on several occasions how images from Voyager 2 first made me aware of other worlds—Jupiter, Saturn, Uranus, Neptune, and their moons—as real places. Today, even with my (somewhat) greater scientific knowledge compared to my young self, I still am impressed with the Voyager missions. Even now, I’m in love with the images, though of course that wasn’t the primary purpose of the Voyager program. The plasma and charged-particle detectors, ultraviolet and radio instruments, and magnetic field analyzers on the probes provided incredible information about the outer planets and their moons. Earth’s magnetic poles aren’t exactly at the North and South geographic poles, but they’re relatively close; Voyager 2 discovered the magnetic fields of Uranus and Neptune are highly displaced from their poles. Voyager 1 found the volcanoes on Io and first measured Titan’s atmosphere—leading to the Huygens Titan lander 20 years later. Jupiter with its moon Io, as seen by the Voyager 2 mission. […]
[…] Modern scanning-tunneling electron microscopes can map the distribution of electric charge, which provides something resembling images of atoms, but it’s not what we would see with our eyes. However, between electron microscopes, the famous oil-drop experiment of Robert Millikan (repeated over and over by physics students, including many of my own), cathode-ray tubes used in oscilloscopes and older TV sets, electron-diffraction experiments, various particle-physics experiments, etc.—over 100 years of study in all—have established the existence of electrons beyond reasonable doubt. […]