Luna 4, or E-6 No.4, 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.
The Luna programme, occasionally called Lunik by western media, is a series of robotic spacecraft missions sent to the Moon by the Soviet Union between 1959 and 1976. Fifteen were successful, each designed as either an orbiter or lander, and accomplished many firsts in space exploration. They also performed many experiments, studying the Moon's chemical composition, gravity, temperature, and radiation.
Luna 9 (Луна-9), internal designation Ye-6 No.13, was an uncrewed space mission of the Soviet Union's Luna programme. On 3 February 1966, the Luna 9 spacecraft became the first spacecraft to achieve a survivable landing on a celestial body.
Luna 10 was a 1966 Soviet lunar robotic spacecraft mission in the Luna program. It was the first artificial satellite of the Moon.
Luna 11 was an uncrewed space mission of the Soviet Union's Luna program. It was also called Lunik 11. Luna 11 was launched towards the Moon from an Earth-orbiting platform and entered lunar orbit on 27 August 1966.
Luna 12 was an unmanned space mission of the Luna program, also called Lunik 12.
Luna 13 was an uncrewed space mission of the Luna program by Soviet Union.
Luna 14 was an uncrewed space mission of the Luna program run by the Soviet Union. It was also called Lunik 14.
Luna 15 was a robotic space mission of the Soviet Luna programme, that crashed into the Moon on 21 July 1969.
Luna 16 was an uncrewed 1970 space mission, part of the Soviet Luna program. It was the first robotic probe to land on the Moon and return a sample of lunar soil to Earth. The 101 grams sample was returned from Mare Fecunditatis. It represented the first successful lunar sample return mission by the Soviet Union and was the third lunar sample return mission overall.
LOK Luna 17 was an uncrewed space mission of the Luna program, also called Lunik 17. It deployed the first robotic rover onto the surface of the Moon.
Luna 18, part of the Ye-8-5 series, was an uncrewed space mission of the Luna program.
Luna 19, was an unmanned space mission of the Luna program. Luna 19 extended the systematic study of lunar gravitational fields and location of mascons. It also studied the lunar radiation environment, the gamma-active lunar surface, and the solar wind. Photographic coverage via a television system was also obtained.
Luna 20 was the second of three successful Soviet lunar sample return missions. It was flown as part of the Luna program as a robotic competitor to the six successful Apollo lunar sample return missions.
Luna 21 was an uncrewed space mission, and its spacecraft, of the Luna program, also called Lunik 21, in 1973. The spacecraft landed on the Moon and deployed the second Soviet lunar rover, Lunokhod 2. The primary objectives of the mission were to collect images of the lunar surface, examine ambient light levels to determine the feasibility of astronomical observations from the Moon, perform laser ranging experiments from Earth, observe solar X-rays, measure local magnetic fields, and study mechanical properties of the lunar surface material.
Luna 23 was an uncrewed space mission of the Luna program developed by the Soviet Union.
Luna 24 was a robotic probe of the Soviet Union's Luna programme. The last of the Luna series of spacecraft, the mission of the Luna 24 probe was the third Soviet mission to return lunar soil samples from the Moon. The probe landed in Mare Crisium. The mission returned 170.1 g (6.00 oz) of lunar samples to the Earth on 22 August 1976.
The Lunar Orbiter 3 was a spacecraft launched by NASA in 1967 as part of the Lunar Orbiter Program. It was designed primarily to photograph areas of the lunar surface for confirmation of safe landing sites for the Surveyor and Apollo missions. It was also equipped to collect selenodetic, radiation intensity, and micrometeoroid impact data.
Kosmos 111, E-6S No.204, was the first Soviet attempt to orbit a spacecraft around the Moon. The design was similar to the future successful Luna 10 spacecraft. Kosmos 111 was produced in less than a month, one of two spacecraft developed from the E-6 lander bus in a crash program to upstage America's Lunar Orbiter series and to commemorate the 23rd Congress of the Communist Party of the Soviet Union (CPSU), held in March 1966.
Kosmos 305 was the fifth Soviet attempt at an unmanned lunar sample return. It was probably similar in design to the Luna 16 spacecraft. It was launched, on a Proton rocket, on October 22, 1969. The engines on the Block D upper stage failed, terminating the mission. This left the spacecraft stranded in Earth orbit. It re-entered within one orbit.
