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Luna 11

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Luna 11
Stamp commemorating Luna 11
Mission typeLunar orbiter
OperatorSoviet space program
COSPAR ID1966-078A Edit this at Wikidata
SATCAT no.02406
Mission duration38 days
Spacecraft properties
Spacecraft typeE-6LF
ManufacturerGSMZ Lavochkin
Launch mass1640 kg[1]
Dry mass1136 kg
Start of mission
Launch date24 August 1966, 08:03:21 UTC[1]
RocketMolniya-M 8K78M
Launch siteBaikonur, Site 31/6
ContractorTsSKB-Progress
End of mission
Last contact1 October 1966
Decay dateLate 1966 or Early 1967
Orbital parameters
Reference systemSelenocentric
Periselene altitude1898 km
Aposelene altitude2931 km
Inclination27°
Period178 minutes
Epoch24 August 1966 [2]
Lunar orbiter
Orbital insertion27 August 1966, 21:49 GMT
Orbits277
Instruments
Imaging system for lunar photography
Gamma-ray spectrometer
Magnetometer
Radiation detectors
Infrared radiometer
Meteoroid detector
R-1 transmission experiment
← Luna 10
Luna 12 →

Luna 11 (E-6LF series) 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 onboard a Molniya-M and entered lunar orbit on 27 August 1966.

Overview

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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 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. 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. 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.[3] A technological experiment included testing the efficiency of gear transmission in a vacuum as a test for a future lunar rover.[4]

Luna 11, launched only two weeks after the U.S. Lunar Orbiter, entered lunar orbit at 21:49 GMT on 27 August 1966. Parameters were 99 x 742 miles. 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. The spacecraft eventually crashed on the moon on an unknown date.[5]

References

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  1. ^ a b Siddiqi, Asif (2018). Beyond Earth: A Chronicle of Deep Space Exploration, 1958–2016 (PDF) (second ed.). NASA History Program Office.
  2. ^ "NASA - NSSDCA - Spacecraft - Trajectory Details". nssdc.gsfc.nasa.gov. Retrieved 2 May 2018.
  3. ^ Ulivi, Paolo; Harland, David M (2004). Lunar Exploration Human Pioneers and Robot Surveyors. Springer. p. 72. ISBN 185233746X.
  4. ^ Ulivi, Paolo; Harland, David M (2004). Lunar Exploration Human Pioneers and Robot Surveyors. Springer. p. 74. ISBN 185233746X.
  5. ^ Reichl, Eugen (2019). The Soviet Space Program The Lunar Years: 1959-1976. p. 91. ISBN 978-0-7643-5675-9. Retrieved 20 October 2024.