This historic landing of a spacecraft on a comet on Wednesday turned out to be not one but three landings as the craft hopped across the surface.

Because of the failure of a thruster that was to press it against the comet’s surface after touching down, the European Space Agency’s Philae lander, part of the $1.75 billion Rosetta mission, bounded up more than half a mile before falling to the surface of Comet 67P/Churyumov-Gerasimenko again nearly two hours later, more than half a mile away. That is a considerable distance across a comet that is only 2.5 miles wide.

Philae then bounced again, less high, and ended up with only two of its three legs on the surface, tipped against a boulder, a wall of rock or perhaps the side of a hole.

“We are almost vertical, one foot probably in the open air — open space. I’m sorry, there is no air around,” Jean-Pierre Bibring, the lead lander scientist, said at a news conference on Thursday.