Lunar Orbiter 1 to 5
The Lunar Orbiter program was a series of five uncrewed lunar orbiter missions launched by NASA from 1966 through 1967. Intended to help select Apollo landing sites by mapping the Moon's surface, they provided the first photographs from lunar orbit and photographed both the Moon and Earth. All were successful, and upon completing their missions, they were intentionally deorbited and crashed on the lunar surface, the last of which came down in 1968
(NOTE: This should NOT be confused with the more recent Lunar Reconnaissance Orbiter (LRO) currently active in low lunar orbit since 2009)
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