A

David

Darling

hard landing

A hard landing is the deliberate destructive impact of a space vehicle on a predetermined celestial target. Among the objectives of such a mission may be to test propulsion and guidance or to take photographs of selected regions to prepare the way for later soft landing missions (as in the case of the Ranger probes); to create a seismic disturbance that can be registered by sensors on the surface (as in the case of spent rocket stages and Lunar Module ascent stages in the Apollo Project); or to splash material from beneath the surface into space so that it can be collected and/or analyzed by a mother craft (as in the case of Deep Impact).

 

The term is also applied to an unintentional destructive impact of a spacecraft whose inbound trajectory is incorrect or whose braking and/or landing mechanisms have failed (as in the case of the Beagle 2 Mars lander).