1950s-70s USA and Russia philatelic covers that are related to the early satellites development, manned and unmanned spaceflights to the moon.
1967-02-05 USA Lunar Orbiter 3
Lunar Orbiter 3, boosted by its Atlas Agena D carrier was launched on 4 February 1967, and entered moon orbit on the 8th. Its mission was to photograph the prime site in eastern Mare Tranquillitatis, one of the potential landing site for Apollo.
The orbit of Lunar Orbiter 3 was altered several times during the mission to give controllers on Earth more experience with communications during lunar orbit. Lunar Orbiter 3 drew great attention when it photographed the Surveyor 1 spacecraft that landed on the moon in early June 1966. The mission ended on 9 October 1967 when it was deliberately crashed the spacecraft into the Moon.