Luna 15 was a

robotic space mission A robotic spacecraft is an uncrewed spacecraft, usually under telerobotic control. A robotic spacecraft designed to make scientific research measurements is often called a space probe. Many space missions are more suited to telerobotic rather ...

of the Soviet

Luna programme The Luna programme (from the Russian word "Luna" meaning "Moon"), occasionally called ''Lunik'' by western media, was a series of robotic spacecraft missions sent to the Moon by the Soviet Union between 1959 and 1976. Fifteen were successful, ...

, that crashed into the Moon on 21 July 1969. On 21 July 1969, while

Apollo 11 Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module ''Eagle'' on July 20, 1969, at 20:17 UTC, ...

astronauts finished the first human moonwalk, Luna 15, a robotic Soviet spacecraft in lunar orbit at the time, began its descent to the

lunar surface The geology of the Moon (sometimes called selenology, although the latter term can refer more generally to " lunar science") is quite different from that of Earth. The Moon lacks a true atmosphere, which eliminates erosion due to weather. It does ...

. Launched three days before the Apollo 11 mission, it was the second Soviet attempt to return lunar soil back to Earth with a goal to outstrip the US in achieving a sample return in the

Moon race The Space Race was a 20th-century competition between two Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the tw ...

. The previous mission, designated E-8-5-402, launched 14 June 1969, did not achieve Earth orbit because the third stage of its launch vehicle failed to ignite. The Luna 15 lander crashed into the Moon at 15:50 UT, hours before the scheduled American lift off from the Moon.

Mission

Luna 15 was capable of studying circumlunar space, the lunar gravitational field, and the chemical composition of lunar rocks. It was also capable of providing lunar surface photography. Luna 15 was placed in an intermediate Earth orbit after launch and was then sent toward the Moon. After a mid-course correction the day after launch, Luna 15 entered lunar orbit at 10:00 UT on 17 July 1969. The spacecraft remained in lunar orbit for two days while controllers checked all on-board systems and performed two orbital manoeuvres. After completing 86 communications sessions and 52 orbits of the Moon at various inclinations and altitudes, it began its descent. Astronauts

Armstrong Armstrong may refer to: Places * Armstrong Creek (disambiguation), various places Antarctica * Armstrong Reef, Biscoe Islands Argentina * Armstrong, Santa Fe Australia * Armstrong, Victoria Canada * Armstrong, British Columbia * Armstrong, ...

and

Aldrin Aldrin is an organochlorine insecticide that was widely used until the 1990s, when it was banned in most countries. Aldrin is a member of the so-called "classic organochlorines" (COC) group of pesticides. COCs enjoyed a very sharp rise in popular ...

had already set foot on the Moon when Luna 15 fired its main

retrorocket A retrorocket (short for ''retrograde rocket'') is a rocket engine providing thrust opposing the motion of a vehicle, thereby causing it to decelerate. They have mostly been used in spacecraft, with more limited use in short-runway aircraft land ...

engine to initiate descent to the surface at 15:47 UT on 21 July 1969. Transmissions ceased four minutes after de-orbit, at a calculated altitude of . The spacecraft had probably crashed into the side of a mountain. Impact coordinates were 17° north latitude and 60° east longitude, in

Mare Crisium Mare Crisium (Latin ''crisium'', the "Sea of Crises") is a lunar mare located in the Moon's Crisium basin, just northeast of Mare Tranquillitatis. The basin is of the Pre-Imbrian period, 4.55 to 3.85 billion years ago. Characteristics Mare Cri ...

. This (the impact site of LUNA 15) is some NNE of the Apollo 11 LZ, in a direction of 328 degrees. An audio recording of the minutes in which British technicians at the radio telescope facility in

Jodrell Bank Jodrell Bank Observatory () in Cheshire, England, hosts a number of radio telescopes as part of the Jodrell Bank Centre for Astrophysics at the University of Manchester. The observatory was established in 1945 by Bernard Lovell, a radio astro ...

observed Luna 15's descent was first made available to the public on 3 July 2009.

Implications

In a race to reach the Moon and return to Earth, the parallel missions of Luna 15 and Apollo 11 represented, in many ways, the culmination of the

Space Race The Space Race was a 20th-century competition between two Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the t ...

between the space programs of the United States and the Soviet Union in the 1960s. The simultaneous missions became one of the first instances of Soviet–American space communication: the Soviet Union released Luna 15's flight plan to ensure it would not collide with Apollo 11, although its exact mission was not publicized.

References

External links

Zarya - Luna programme chronology

NASA NSSDC Master Catalog
{{Orbital launches in 1969 Luna programme Sample return missions Missions to the Moon Spacecraft launched in 1969 1969 in the Soviet Union Spacecraft that impacted the Moon Spacecraft that orbited the Moon 1969 on the Moon