Lunar Reconnaissance Orbiter
The Lunar Reconaissance Orbiter (LRO) is a NASA space probe launched in 2009-Jun-18 with LCROSS and sent to a polar orbit around the Moon to collect data from the lunar surface to aid future manned and robotic missions there. It is still currently active as of 2023, making it the longest lunar mission ever attempted.
NOTE: This should not be confused with the earlier Lunar Orbiter program that saw five spacecraft that orbited the Moon between 1966 and 1968
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