Philae (comet lander)
Philae is a European Space Agency device which landed on the nucleus of a comet on 12th November 2014, the first time in history that this had been achieved. Philae initially bounced off the surface, ultimately coming to rest in a position that did not allow enough sunlight to reach its solar panels, so ceased sending back data after three days, when its batteries ran out. Its harpoons and screws also failed to anchor it to the surface, which was much harder than expected.
As part of a wider mission to investigate comet activity, Philae was launched on 2nd March 2004 with the Rosetta spacecraft, which took up a position in orbit of comet 67P/Churyumov–Gerasimenko prior to releasing the lander.