A soft landing is the process of bringing a spacecraft down to a planetary surface at a low enough velocity that neither the vehicle nor its instruments are damaged. It requires complex deceleration techniques, such as retrorockets, parachutes, or airbags, to counteract gravity and atmospheric entry speeds. Mission planners consider it the ultimate test of a lander's autonomous guidance and propulsion systems.
Heard on the job
Telemetry confirms the retrorockets fired nominally, and we have achieved a soft landing in the target crater.
Do not mix it up with
- Lithobraking: Lithobraking intentionally uses the ground to slow down, often destroying the craft, whereas a soft landing uses propulsion or drag to land intact.