Lunar Atmosphere and Dust Environment Explorer

Lunar Atmosphere and Dust Environment Explorer (LADEE), U.S. spacecraft designed to study the thin lunar atmosphere and the amount of dust in it before it is altered by human activity on the Moon. LADEE, launched on September 6, 2013, was the first spacecraft based on the Modular Common Spacecraft Bus (MCSB), an inexpensive modular platform that was designed to do away with the need to build a new spacecraft for each new mission. To save fuel, the spacecraft traveled very slowly, reaching lunar orbit on October 6. (Most other missions to the Moon have taken only a few days and thus burned their fuel much faster.) Once it reached the Moon, LADEE studied the atmosphere with a mass spectrometer, an ultraviolet/visible-light spectrometer, and a dust detector from a near-equatorial orbit about 50 km (30 miles) above the lunar surface. At the end of its mission, LADEE was placed in an extremely low orbit less than 2 km (1 mile) above the lunar surface, and it impacted on the Moon on April 17, 2014.