It's only been two days at the big Fall Meeting of the American Geophysical Union in San Francisco, and I'm already having to ration my energy. The flood of science is exhilarating, and the presence of so many highly talented people is stimulating. But the hours are long, the schedule is hectic, and it took lots of extra work beforehand to free up the time.
One of Monday's highlights for me was a session on habitability, or how friendly a planetary system is for life. It was exciting because we now have collected thousands of planets beyond our own eight, circling other stars. The diagrams on display reminded me of the Hertzsprung-Russell graph that astronomers use to display hundreds of stars at different stages of their life cycle. We're finding that a lot of these exoplanets are way out of placegas giants closer to their stars than Mercury, and a lot of very small planets. The universe is pretty strange, and isn't that great?
Tuesday I learned in a poster that the Mars landers have found 19 meteorites so far. The same traverses on a random Earth location would not turn up any. Because the meteorites are basically pure iron, they should be exceptionally sensitive to climatic conditions on Mars, and the Curiosity lander is giving them very close attention. I saw another poster that described a simple and clever way of making seismic signals for surveying purposes, working like the airguns and detonations that ships use in the sea: helicopters drop big sandbags onto the ground. This is great for dangerous locations like volcanoes. My favorite AGU thing is stuff like this that makes me say, Why didn't I think of that?