Lithobraking is a tongue-in-cheek aerospace term for decelerating a vehicle by impacting the surface of a planet or moon. While aerobraking uses the atmosphere to slow down, lithobraking uses rock. It usually refers to a catastrophic crash due to a failure in the landing systems, though it can technically describe intentional, heavily cushioned impacts like the airbag landings of early Mars rovers.
Heard on the job
The descent engine failed at two kilometers up, so the probe completed its mission with some unplanned lithobraking.
Insider tip
Never use this in a formal failure report. It is dark humor reserved for the break room or casual post-mission analysis.