Venera 7

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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 (1970-08-17UTC05:38:22Z) UTC
Rocket Molniya-M
Launch site Baikonur 31/6
End of mission
Last contact 15 December 1970, 06:00 (1970-12-15UTC07Z) 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 man-made spacecraft to land successfully on another planet, and to transmit data from there back to Earth.[1]

Launch[edit]

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[edit]

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 / -5; 351.[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[edit]

  1. ^ "Science: Onward from Venus". TIME. 8 February 1971. Retrieved 2 January 2013. 
  2. ^ a b c d e f g h i j k 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. ^ a b c Larry Klaes, THE SOVIETS AND VENUS, PART 1, 1993.

External links[edit]