It was high drama that continued into the afternoon as questions arose about whether the probe, in fact, stuck the landing despite the fact that harpoons designed to anchor it failed to fire. Then the probe's batteries appeared to conk out.
Many in the United States bemoaned the fact that it was a European agency, not an American one, that led the mission (although NASA was part of a consortium of partners for the mission).
Actually, NASA has done something very similar. The space agency made an impromptu landing on an asteroid called Eros on February 12, 2001.
The agency's Near Earth Asteroid Rendezvous-Shoemaker (NEAR-Shoemaker), the first mission to orbit an asteroid, wasn't designed to land, but when the mission ended, NASA decided to give it a try. It worked. The probe continued to send back data for several days and made its last call back to Earth on Feb. 28, 2001.
There are dozens of other exciting unmanned missions underway -- and several really cool ones that have wrapped up. Take a look at the gallery above, which highlights 11 fascinating space missions.