Venera 2MV-2 No.1, also known as Sputnik 21 in the West, was a Soviet spacecraft, which was launched in 1962 as part of the Venera programme, and was intended to make a flyby of Venus. Due to a problem with the rocket which launched it, it failed to leave low Earth orbit, and reentered the atmosphere a few days later. It was the only Venera 2MV-2 spacecraft ever launched. Venera 2MV-2 No.1 was launched at 00:59:13 UTC on 12 September 1962, atop a Molniya 8K78 carrier rocket flying from Site 1/5 at the Baikonur Cosmodrome. The rocket performed nominally until cutoff of the Blok I stage, following injection into a low Earth orbit.

Wikipedia: https://en.wikipedia.org/wiki/Sputnik_21. Original timeline Wikipedia link: https://en.wikipedia.org/wiki/Sputnik_program. Related NASA reference: https://nssdc.gsfc.nasa.gov/planetary/chronology.html#1962. Description adapted from Wikipedia contributors (CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0/).