1957-10-04 USSR Sputnik 1

On 4 October 1957, the Soviet Union launched the world's first artificial satellite, Sputnik 1. Sputnik 1 provided scientists with data about the nature and ion density of the Earth’s upper atmosphere, how radio frequencies would work in space and thus whether astronauts would be able to communicate with a base on Earth. This post card shows a replica of Sputnik 1.
This cover was produced by KNIGA. The Moscow 4 October 1957 postmark on the cover was likely backdated since Sputnik 1 was never announced to the public before it was successfully launched.
4 October 1957 Moscow M-127 postmark (unofficial).
Russian Sputnik 1 stamp (indigo color on bluish colored paper, designed by Ye. Gundobin) on FDC issued on 4 November 1957 to commemorate the launching of the world's first artificial satellite.
Russian Sputnik 1 overprint stamp (bright-blue color on white paper) on FDC issued on 28 December 1957.