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Mars 7

NSSDCA/COSPAR ID: 1973-053A

Description

Mars 4, 5, 6, and 7 comprised an associated group of Soviet spacecraft launched towards Mars in July and August of 1973. The Mars 7 interplanetary station was intended to be a Mars lander. It consisted of a flyby bus and a descent module. The descent module was designed to enter the martian atmosphere and make in-situ studies of the atmosphere and surface, but a malfunction on board caused the lander to miss the planet.

Mission Profile

Mars 7 successfully lifted off into an intermediate Earth orbit on a Proton SL-12/D-1-e booster and then launched into a Mars transfer trajectory. Total fueled launch mass of the lander and bus was 3260 kg. After one course correction burn on 16 August 1973, it reached Mars on 9 March 1974. Due to a problem in the operation of one of the onboard systems (attitude control or retro-rockets) the landing probe separated prematurely (4 hours before encounter) and missed the planet by 1300 km. The early separation was probably due to a computer chip error which resulted in degradation of the systems during the trip to Mars. The intended landing site was 50 S, 28 W and landed mass would have been 635 kg. The lander and bus continued on into heliocentric orbits.

Scientific Instrumentation

The Mars 7 Descent Module carried a panoramic telephotometer to image the martian surface around the lander, atmospheric temperature, pressure, density, and wind sensors, an accelerometer to measure atmospheric density during the descent, a mass spectrometer to estimate atmospheric composition, a radio altimeter, an activation analysis experiment to study soil composition, and mechanical properties soil sensors. The flyby module contained a telephotometer to image Mars, a Lyman alpha sensor to search for hydrogen in the upper atmosphere, a magnetometer, an ion trap and narrow angle electrostatic plasma sensor to study the solar wind and its interaction with Mars, solar cosmic ray sensors, micrometeorite sensors, and a French-supplied solar radiometer to measure solar long-wavelength radio emissions. It was also equipped to perform a radio occultation experiment to profile the atmosphere and ionosphere.

Spacecraft image for illustrative purposes - not necessarily in the public domain.

Alternate Names

  • M-73 No.51P
  • 06776

Facts in Brief

Launch Date: 1973-08-09
Launch Vehicle: Proton Booster Plus Upper Stage and Escape Stages
Launch Site: Tyuratam (Baikonur Cosmodrome), U.S.S.R
Mass: 1200.0 kg

Funding Agency

  • Unknown (U.S.S.R)

Disciplines

  • Planetary Science
  • Space Physics

Additional Information

Questions or comments about this spacecraft can be directed to: Dr. David R. Williams.

 

Personnel

NameRoleOriginal AffiliationE-mail
Mr. Artem IvankovGeneral ContactLavochkin Associationartem.ivankov@laspace.ru

Selected References

Shelton, W., Soviet space exploration - the first decade, Arthur Barker Ltd., Unnumbered, London, England, 1969.

Harvey, B., The new Russian space programme from competition to collaboration, John Wiley & Sons, Chichester, England, 1996.

Perminov, V. G., The difficult road to Mars - A brief history of Mars exploration in the Soviet Union, NASA, No. 15, Wash, DC, July 1999.

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