Mars 2
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Names | M-71 No. 171 |
---|---|
Mission type | Orbiter and lander |
Operator | Soviet Union |
COSPAR ID | Orbiter: 1971-045A Lander: 1971-045D |
SATCAT no. | Orbiter: 5234 Lander: 5739 |
Mission duration | 461 days |
Spacecraft properties | |
Manufacturer | OKB-1 |
Launch mass | Combined: 4,650 kg (10,250 lb) Orbiter: 3,440 kg (7,580 lb) Lander: 1,210 kg (2,670 lb)[1] |
Start of mission | |
Launch date | 16:22:44, May 19, 1971 (UTC) |
Rocket | Proton K with Blok D upper stage |
End of mission | |
Disposal | Decommissioned |
Deactivated | August 22, 1972 |
Last contact | last data transmission July 1972[2] |
Orbital parameters | |
Reference system | Areocentric |
Mars orbiter | |
Orbital insertion | 27 November 1971 |
Orbits | 362 |
Orbital parameters | |
Periareion altitude | 1,380 km (860 mi) |
Apoareion altitude | 24,940 km (15,500 mi) |
Inclination | 48.9° |
Mars lander | |
Spacecraft component | Mars 2 Lander |
Landing date | 27 November 1971 |
Landing site | 45°S 47°E / 45°S 47°E |
The Mars 2 was an uncrewed
Overview
- Launch Date/Time:
- Mars 2: 19 May 1971 at 16:22:44 UTC
- Launch mass (including fuel):
- Combined: 4,650 kg (10,250 lb)
- Orbiter: 3,440 kg (7,580 lb)
- Lander: 1,210 kg (2,670 lb)
- On-orbit dry mass: 2,265 kg (4,993 lb)
- Dimensions: 4.1 m (13.5 ft) tall, 2 m (6.6 ft) across (5.9 m (19.4 ft) across with solar panels deployed)
Launch
On 19 May 1971, the Proton-K heavy launch vehicle launched the probe from Baikonur Cosmodrome. After the first stage separated the second stage was ignited. The third stage engine blasted Mars 2 into parking orbit, then the Blok D upper stage sent Mars 2 on the trans-Mars trajectory.
Orbiter
The Orbiter type was the 4MV, used also for Mars-3 and later Mars and Venera Probes. The orbiter engine performed a burn to put the spacecraft into a 1,380-by-2,494-kilometre (857 mi × 1,550 mi), 18-hour orbit about Mars with an inclination of 48.9 degrees. Scientific instruments were generally turned on for about 30 minutes near periapsis.
The orbiter's primary scientific objectives were to image the Martian surface and clouds, determine the temperature on Mars, study the topography, composition and physical properties of the surface, measure properties of the atmosphere, monitor the solar wind and the interplanetary and Martian magnetic fields, and act as a communications relay to send signals from the landers to the Earth.
By coincidence, a particularly large
The Mars 2 orbiter sent back data covering the period from December 1971 to March 1972, although transmissions continued through August. It was announced that Mars 2 and Mars 3 had completed their missions by 22 August 1972, after 362 orbits. The probe, combined with Mars 3, sent back a total of 60 pictures. The images and data revealed mountains as high as 22 kilometres (14 mi), atomic hydrogen and oxygen in the upper atmosphere, surface temperatures ranging from −110 to 13 °C (−166 to 55 °F), surface pressures of 5.5 to 6 mbar (0.55 to 0.6
Lander
Lander spacecraft system
The Mars 2 descent module was mounted on the bus/orbiter opposite the propulsion system. It consisted of a spherical 1.2 metres (3 ft 11 in) diameter landing capsule, a 2.9 metres (9 ft 6 in) diameter conical aerodynamic braking shield, a parachute system and retro-rockets.
The entire descent module had a fueled mass of 1,210 kilograms (2,670 lb), the spherical landing capsule accounting for 358 kilograms (789 lb) of this. An automatic control system consisting of gas micro-engines and pressurised nitrogen containers provided attitude control. Four "gunpowder" engines were mounted to the outer edge of the cone to control pitch and yaw.
The main and auxiliary parachutes, the engine to initiate the landing, and the radar altimeter were mounted on the top section of the lander. Foam was used to absorb shock within the descent module. The landing capsule had four triangular petals which would open after landing, righting the spacecraft and exposing the instrumentation.
The lander was equipped with two television cameras with a 360 degree view of the surface as well as a
Four aerials protruded from the top of the sphere to provide communications with the orbiter via an onboard radio system. The equipment was powered by batteries which were charged by the orbiter prior to separation. Temperature control was maintained through thermal insulation and a system of radiators. The landing capsule was sterilised before launch to prevent contamination of the Martian environment.
PrOP-M rover
Mars 2 lander had a small 4.5 kilograms (9.9 lb) Mars rover on board, which would move across the surface on skis while connected to the lander with a 15-metre (49 ft) umbilical. Two small metal rods were used for autonomous obstacle avoidance, as radio signals from Earth would take too long to drive the rovers using remote control. The rover carried a dynamic penetrometer and a radiation densitometer.[4]
The main PrOP-M frame was a square box with a small protrusion at the center. The frame was supported on two wide flat skis, one extending down from each side elevating the frame slightly above the surface.
The rover was planned to be placed on the surface after landing by a manipulator arm and to move in the field of view of the television cameras and stop to make measurements every 1.5 metres (4 ft 11 in). The traces of movement in the Martian soil would also be recorded to determine material properties.
Because of the demise of the lander, the rover was not deployed.
Entry, descent, and crash landing
The descent module separated from the orbiter on 27 November 1971 about 4.5 hours before reaching Mars. After entering the atmosphere at approximately 6 km/s, the descent system on the module malfunctioned, possibly because the angle of entry was too steep. The descent sequence did not operate as planned and the parachute did not deploy.[4] The descent module became the first man-made object to impact the surface of Mars. The exact crash site is unknown, but it is estimated to be at 45°S 313°W / 45°S 313°W.[3][5] Attempts to contact the probe after the crash were unsuccessful.
See also
- List of Mars orbiters
- List of missions to Mars
- Mars 1M
- Mars program
- Space exploration
- Timeline of artificial satellites and space probes
- Robotic spacecraft
References
- ^ "NASA - NSSDCA - Spacecraft - Details".
- ^ See Mars 3 article in https://solarsystem.nasa.gov/resources/1060/beyond-earth-a-chronicle-of-deep-space-exploration/
- ^ a b
Pyle, Rod (2012). Destination Mars. ISBN 978-1-61614-589-7.
...Mars 2 and Mars 3. Both reached Mars shortly after Mariner 9. Unfortunately, these Soviet ships were not reprogrammable, as was the case with Mariner 9, and rather than wait out the huge, planet-wide dust storm, they proceeded to follow their programming right on schedule. Landers were dispatched from each, the first crashing and the second apparently reaching the surface intact but losing radio contact immediately. The orbiters fared little better; following their simple logic, both used up their available resources snapping images of the featureless dust clouds below.
- ^ ISBN 0-16-058859-6.
- ^ "Missions to Mars". The Planetary Society.