Luna 4
Luna 4, or E-6 No.4 (Ye-6 series), sometimes known in the West as Sputnik 26, was a Soviet spacecraft launched 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. Mission Luna 4 was launched by a Molniya-L carrier rocket at 08:16:37 UTC on April 2, 1963. Launch occurred from Site 1/5 at the Baikonur Cosmodrome. After reaching an initial parking orbit of , the rocket's upper stage restarted to place Luna 4 onto a translunar trajectory. The spacecraft did not perform a required midcourse correction manoeuvre, which resulted in it missing the Moon by at 1:24 UT on April 5, 1963. It then entered a barycentric 90,000 × 700,000 km Earth orbit. A lecture program entitled Hitting the Moon was scheduled to be broadcast on Radio Moscow at 7:45 p.m. the evening of April 5 but was cancelled. The spacecraft transmitted at 183.6 MHz at least until April 6. Lunar surface close-up photography The purpose of this experiment was to obtain information on the characteristics of the lunar surface.