Venera 7

Venera 7

Venera 7
Mission type Venus Lander
COSPAR ID 1970-060A
SATCAT № 4489
Mission duration 120 days
Spacecraft properties
Spacecraft 4V-1 No.630
Manufacturer Lavochkin
Launch mass 1,180 kilograms (2,600 lb)
Start of mission
Launch date 17 August 1970, 05:38:22 UTC
Rocket Molniya-M
Launch site Baikonur 31/6
End of mission
Last contact 15 December 1970, 06:00 UTC
Orbital parameters
Reference system Heliocentric
Venus lander
Landing date 15 December 1970, 05:37:10 UTC

The Venera 7 (Russian: Венера-7 meaning Venus 7) (manufacturer's designation: 3V (V-70)) was a Soviet spacecraft, part of the Venera series of probes to Venus. When it landed on the Venusian surface, it became the first spacecraft to land successfully on another planet, and to transmit data from there back to Earth.[1]

Launch

The probe was launched from Earth on August 17, 1970, at 05:38 UTC. It consisted of an interplanetary bus based on the 3MV system and a lander.[2] During the flight to Venus two in-course corrections were made using the bus's on-board KDU-414 engine.[2]

Landing

It entered the atmosphere of Venus on December 15, 1970.[2] Unusually the lander remained attached to the interplanetary bus during the initial stages of atmospheric entry.[2] This was to allow the bus to cool the lander to -8°C for as long as possible.[2] The lander was ejected once atmospheric buffeting broke the interplanetary bus's lock-on with Earth.[2] The parachute opened at a height of 60 km and atmospheric testing began with results showing the atmosphere to be 97% carbon dioxide.[2] During the descent the parachute appeared to fail, resulting in a more rapid than planned descent.[2] As a result the lander struck the surface of Venus at about 16.5 metres per second (54 ft/s) at 05:37:10 UTC.[2] Landing coordinates are 5°S 351°E / 5°S 351°E.[3]

The probe appeared to go silent on impact.[2] However, recording tapes kept rolling.[4] A few weeks later, upon a reviewing of the tapes, another 23 minutes of very weak signals were found on them.[4] The spacecraft had landed on Venus and probably bounced onto its side upon impact, leaving the medium gain antenna not aimed correctly for strong signal transmission to Earth.[4] The only data returned from the surface were temperature readings, which gave a temperature of 475 °C (887 °F).[2]

References

  1. "Science: Onward from Venus". TIME. 8 February 1971. Retrieved 2 January 2013.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 Reeves, Robert (1994). The Superpower Space Race: An Explosive Rivalry through the Solar System. Plenum Press. pp. 211–215. ISBN 0-306-44768-1.
  3. Patrick Moore, The data book of astronomy. CRC Press, 2000, p. 92.
    See Table 5-5, Missions to Venus, 1961-2000. Landing near Navka Planitia
  4. 4.0 4.1 4.2 Larry Klaes, THE SOVIETS AND VENUS, PART 1, 1993.

External links