Luna 4, or E-6 No.4 (Ye-6 series), sometimes known in the West as Lunik 4, was a Soviet spacecraft launched in 1963 as part of the Luna program to attempt the first soft landing on the Moon. Following a successful launch, the spacecraft failed to perform a course correction and as a result it missed the Moon, remaining instead in Earth orbit before possibly transitioning into a solar orbit. Though the mission was unsuccessful, it nevertheless marked a new epoch in the Space Race, which culminated in the successful landing of Luna 9 in 1966. On the heels of the successful Luna 3 mission, which returned the first images of the Far Side of the Moon, the Soviet Union turned its attention to learning more about the lunar surface and whether it was solid enough to land and build structures upon.

Wikipedia: https://en.wikipedia.org/wiki/Luna_4. Related NASA reference: https://nssdc.gsfc.nasa.gov/planetary/chronology.html#1963. Description adapted from Wikipedia contributors (CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0/).