1950s-70s USA and Russia philatelic covers that are related to the early satellites development, manned and unmanned spaceflights to the moon.
1959-09-12 USSR Luna 2
In September 1959, the Soviet Union responded by becoming the first to place an object on the moon when they struck the lunar surface with their Luna 2. Launched on 12 September 1959 and impact moon on 14 September 1959, Luna 2 was the first spacecraft to land on another celestial body. The spacecraft impacted on the moon's surface just east of the Sea of Serenity near the craters Aristides, Archimedes, and Autolycus. The spacecraft did not detect a magnetic field around the moon.