This photo is making the rounds of Twitter, Facebook, Google+, and whatever other social network you care to name today. It was shot by astronaut Ron Garan from the Space Station, and it's a meteor seen from above. Way cool.
Since the Galileo mission discovered tiny Dactyl circling Ida in 1993, quite a lot of asteroid systems have been found to be binary; there are even a few triples. So it's quite reasonable to guess that two of the biggest asteroids, Ceres and Vesta, might also have satellites.
Saturn's raging northern storm has been watched since it began by amateur astronomers, and now Cassini is getting in to the act too. Presumably once astronomers realized the magnitude of what was going on, some of Earth's great observatories were also occasionally pointed at the ringed planet to watch the storm grow.
As part of a big, ongoing project to make a comparison chart of the dimensions and physical properties of solar system objects I've spent the morning tackling the difficult problem of summarizing the physical characteristics of the biggest things that are out there beyond Neptune.
Welcome 2011! I can't wait for what this year has in store. The prize for all of you who have enjoyed opening each door in the Planetary Society's 2010 advent calendar is one of the best views we can get of one of the biggest objects in the asteroid belt, Vesta.
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