Lunar Reconnaissance Orbiter

United States spacecraft

Also known as: LRO

Written by

Dave Dooling

Fact-checked by

Britannica Editors

Last updated

Oct. 1, 2026 •History

Lunar Reconnaissance Orbiter (LRO), a U.S. spacecraft that mapped the surface of the Moon in order to help select ideal sites for uncrewed and eventually crewed lunar landers. After a series of postponements, the LRO was successfully launched on June 18, 2009, from Cape Canaveral, Florida, on an Atlas rocket that also launched the Lunar Crater Observation and Sensing Satellite (LCROSS), which was designed to seek water at the lunar south pole. After transferring from...