Luna 11 (E-6LF series) was an uncrewed space mission of the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...

Luna program 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 ...

. It was also called Lunik 11. Luna 11 was launched towards the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

from an Earth-orbiting platform and entered lunar orbit on 27 August 1966.

Overview

The objectives of the mission included the study of: * lunar gamma and X-ray emissions in order to determine the Moon's chemical composition; * lunar gravitational anomalies; * the concentration of meteorite streams near the Moon; * the intensity of hard

corpuscular radiation The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between . The composition of the sola ...

near the Moon. 137 radio transmissions and 277 orbits of the Moon were completed before the batteries failed on 1 October 1966. This subset of the "second-generation" Luna spacecraft, the E-6LF, was designed to take the first photographs of the surface of the Moon from lunar orbit. A secondary objective was to obtain data on mass concentrations ("mascons") on the Moon first detected by

Luna 10 Luna 10 (or Lunik 10) was a 1966 Soviet lunar robotic spacecraft mission in the Luna program. It was the first artificial satellite of the Moon. Luna 10 conducted extensive research in lunar orbit, gathering important data on the strength of ...

. Using the Ye-6 bus, a suite of scientific instruments (plus an imaging system similar to the one used on

Zond 3 Zond 3 was a 1965 space probe which performed a flyby of the Moon far side, taking a number of quality photographs for its time. It was a member of the Soviet Zond program while also being part of the Mars 3MV project. It was unrelated to Zond s ...

) replaced the small lander capsule used on the soft-landing flights. The resolution of the photos was 15 to 20 meters. To reduce problems caused by damage to the film due to solar radiation it was planned to take all photos within the first 24 hours of lunar orbits. A technological experiment included testing the efficiency of gear transmission in a vacuum as a test for a future lunar rover. Luna 11, launched only two weeks after the U.S.

Lunar Orbiter The Lunar Orbiter program was a series of five uncrewed lunar orbiter missions launched by the United States from 1966 through 1967. Intended to help select Apollo landing sites by mapping the Moon's surface, they provided the first photographs ...

, entered lunar orbit at 21:49 GMT on 27 August 1966. Parameters were 160 x 1193 kilometers. During the mission, the TV camera failed to return usable images because the spacecraft lost proper orientation to face the lunar surface when a foreign object was lodged in the nozzle of one of the attitude-control thrusters. The other instruments functioned without fault before the mission formally ended on 1 October 1966 after the power supply had been depleted.

References

External links

Zarya - Luna programme chronology
{{Orbital launches in 1966 Luna programme Spacecraft launched in 1966 1966 in the Soviet Union Spacecraft launched by Molniya-M rockets Spacecraft that orbited the Moon Non Earth orbiting satellites of the Soviet Union