The Luna programme (from the Russian word Ëóíà "Luna" meaning "Moon"), occasionally called Lunik or Lunnik, was 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. Twenty-four spacecraft were formally given the Luna designation, although more were launched. Those that failed to reach orbit were not publicly acknowledged at the time, and not assigned a Luna number. Those that failed in low Earth orbit were usually given Cosmos designations. The estimated cost of Luna Program was about $4.5 billion. Achievements Luna 1 missed its intended impact with the Moon and became the first spacecraft to fall into orbit around the Sun. In 1959, the Luna 2 mission successfully impacted upon the lunar surface, becoming the first man-made object to reach the Moon. Luna 3 rounded the Moon later that year, and returned the first photographs of its far side, which can never be seen from Earth. Luna 9 became the first probe to achieve a soft landing on another planetary body (February 1966). It returned five black and white stereoscopic circular panoramas, which were the first close-up shots of the Lunar surface. Later that year Luna 10 became the first artificial satellite of the Moon. Luna 17 and Luna 21 carried vehic
es that roamed around on the Moon's terrain (see Lunokhod programme). Another major achievement of the Luna programme, with the Luna 16, Luna 20 and Luna 24 spacecraft, was the ability to collect samples of lunar soil and return them to Earth, by 1970. The program returned 0.326 kg of lunar samples. The Luna missions were the first space-exploration sample return missions to rely solely on advanced robotics. Other notable missions Luna 15, also designed to return soil samples from the lunar surface, underwent its mission at the same time as the Apollo 11 mission. Neil Armstrong and Buzz Aldrin were already on the lunar surface when Luna 15 began its descent, and the spacecraft crashed into a mountain minutes later.Failed missions While the programme was active, it was Soviet practice not to release any details of missions which had failed to achieve orbit. This resulted in Western observers assigning their own designations to the missions, for example Luna E-1 No.1, the first failure of 1958 which NASA believed was associated with the Luna programme was known as Luna 1958A. NASA identified a spacecraft which it referred to as Luna 1966A as having launched on 30 April 1966, a spacecraft which it referred to as Luna 1969B as having launched on 15 April 1969, and a spacecraft which it referred to as Luna 1970B as having launched on 19 February 1970. When details of Soviet launches were later disclosed, no launches of Luna spacecraft were found to have occurred on those dates.