The module used by Apollo astronauts to land on the Moon. Carrying two astronauts, it disengaged from the command and service modules (CSM) orbiting the Moon. Its descent stage had retrorockets to slow it down and four legs whose pads contained probes to register a landing. The ascent stage had an engine to launch the astronauts back to a rendezvous with the CSM.

The LM was built by the Grumman Aircraft Engineering Corporation (later Grumman Aerospace) and stood 7 m tall on the Moon's surface. Since it only flew in space and was designed for the Moon's weak gravity, the LM was not streamlined and was so delicate it would have collapsed on the Earth's surface. The first LM to land on the Moon in 1969 for the Apollo 11 mission was named the Eagle, inspiring astronaut Neil Armstrong to announce, ‘The Eagle has landed.’