Luna 11

Luna 11

Luna 11
Mission type	Lunar orbiter
COSPAR ID	1966-078A
Mission duration	38 days
Spacecraft properties
Spacecraft type	E-6LF
Manufacturer	GSMZ Lavochkin
Launch mass	1,640 kilograms (3,620 lb)
Start of mission
Launch date	August 24, 1966, 08:09:00 UTC
Rocket	Molniya-M 8K78M
Launch site	Baikonur 31/6
End of mission
Last contact	October 1, 1966
Orbital parameters
Reference system	Selenocentric
Semi-major axis	2,414.5 kilometres (1,500.3 mi)
Eccentricity	0.22
Periselene	1,898 kilometres (1,179 mi)
Aposelene	2,931 kilometres (1,821 mi)
Inclination	27 degrees
Period	178 minutes
Lunar orbiter
Orbital insertion	August 27, 1966, 21:49 UTC
Orbits	277
Instruments
Imaging system for lunar photography Gamma-ray spectrometer Magnetometer Radiation detectors Infrared radiometer Meteoroid detector R-1 transmission experiment

Luna 11 (E-6LF series) was an unmanned 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.

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 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 Ye-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. Using the Ye-6 bus, a suite of scientific instruments (plus an imaging system similar to the one used on Zond 3) replaced the small lander capsule used on the soft-landing flights. The resolution of the photos was 15 to 20 meters. A technological experiment included testing the efficiency of gear transmission in vacuum as a test for a future lunar rover.

Luna 11, launched only two weeks after the U.S. Lunar Orbiter, entered lunar orbit at 21:49 UT on 27 August. Parameters were 160 x 1,193 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.

External links

• Zarya - Luna programme chronology