Mars 6

Launch data: Designation 06768 / 73052A Launch date 05 Aug 1973 - 17:45:48 UT Launch site B, LC-81/23 Launch vehicle Proton-K/D (#281-01 8K82K/11S824) Satellite type  3MP N° 50P Mission Mars probe Heliocentric orbit Perihelion / Aphelion  1.01 x 1.67 AU Eccentricity  0.24 Inclination  2.2? deg Period  566 days

Specifications: Prime contractor   Operator   Mass at launch 4650 kg Dry mass 2060? kg Dimension  2.7 long - 2.3 dia Basic shape  Cylinder + 2 panels Solar array   Soft landing Lifetime Indefinity >

Description:

• Mars spacecraft series built for 1973 missions. Due to unfavorable position of Mars during that campaign, separate versions built: two intended to orbit Mars and map the surface, and two to land capsules. The orbiters were equipped with instrumentation to study the composition, structure, and properties of the Martian atmosphere and surface, including an imaging device, a 256 channel gamma-ray spectrometer mounted on a boom and a Lyman-Alpha photometer. The landers would have separated from their uninstrumented bus, entered the atmosphere, where a parachute opened, slowing the descent. The lander equipment included a Lyman-Alpha photometer and a Bennett mass analyzer. Unfortunately, this entire series of spacecraft experienced failures on arrival at Mars due to pre-flight test of the electronics with helium, which resulted in degradation of the computer chips during the journey to Mars. Orbiters had a launch mass of 3444 kg, and landers 3260 kg.

Mission details:

• Mars probe intended to make a soft landing on Mars. Total fueled launch mass of the lander and orbital bus was 3260 kg. It reached Mars on 12 March 1974, separated from the bus, and entered the atmosphere, where a parachute opened, slowing the descent. As the probe descended through the atmosphere it transmitted data for 150 seconds, representing the first data returned from the atmosphere of Mars. Unfortunately, the data were largely unreadable due to a flaw in a computer chip which led to degradation of the system during its journey to Mars. When the retro-rockets fired for landing, contact was lost with the craft.
• Mars 6 landed at about 24 degrees south, 25 degrees west in the Margaritifer Terra (Margaritifer Sinus region) of Mars. Bus ended up in a final heliocentric orbit 1.01 x 1.67 AU, 2.2 degree inclination, 567 day period.