Lunar Prospector

Lunar Prospector was a spacecraft that orbited the Moon for 19 months in 1998-99. From a low polar orbit, it mapped surface composition including lunar hydrogen deposits, measured magnetic and gravity fields, and studied lunar outgassing events. The mission ended July 31, 1999, when the orbiter was deliberately crashed into a crater near the lunar south pole.

Data from the mission provided detailed mapping of the surface composition of the Moon, and helped to improve understanding of the origin, evolution, current state, and resources of the Moon. The mission identified the presence of hydrogen, implying deposits of ice on the Moon. Several articles on the scientific results were published in the journal Science.

Lunar Prospector was the third mission selected by NASA for full development and construction as part of the Discovery Program. It was managed by NASA Ames Research Center with the prime contractor being Lockheed Martin; it cost $62.8 million. The Principal Investigator for the mission was . His personal account of the mission, Lunar Prospector: Against all Odds, is highly critical of the bureaucracy of NASA overall, and of its contractors.