[Jack Hydrazine]

But it does have a cold gas thruster system to keep it from bouncing off the comet.

http://spaceflightnow.com/2014/11/12/video-mission-control-celebrates-separation-as-anxiety-builds-over-landing/

[prisoner6]

Yup, they couldn’t get that to prime and last I heard it was inoperative. For those harpoons to work the surface better be relatively soft. If it’s really hard rock/metal...that could be a big problem.