Only 12 human beings have walked on the surface of another world: two astronauts from each of Apollo missions 11, 12, 14, 15, 16, and 17. (The third astronaut on each of these missions didn’t descent to the surface in the Lunar Modules, but stayed in lunar orbit.) Even if you include the other astronauts who have orbited the Moon, that number is very small, and unlikely to grow significantly for the near future.
However, since 2009, the Lunar Reconnaissance Orbiter has been taking high-resolution images of the Moon’s surface, and creating a three-dimensional map. Not only that, you can participate from home, using your web browser. A citizen science project known as Moon Zoo lets you help describe craters and boulders on the lunar surface on three possible levels of detail. As with other citizen science projects, you can choose how much time you want to spend on it: if you only have a few minutes during a coffee break, you can cover just one or two images. If you get hooked, with time you can become one of their experts!
Moon Zoo is part of the Zooniverse, a large collection of citizen science projects that includes the Galaxy Zoo, which I mentioned in my earlier essay for the Culture of Science. I’m a big fan of citizen science in general, so it seemed overdue for me to highlight the Moon Zoo on Moonday. Go check it out, learn something, and above all, have fun!
Update: if you are on Twitter, you can also follow Moon Zoo there: @MoonZoo .