Venera 11

Venera 11
Seal of Venera 11
OperatorSoviet Academy of Sciences
COSPAR ID1978-084A
1978-084D
SATCAT no.11020
11027
Mission durationTravel: 3 months and 16 days
Lander: 95 minutes
Spacecraft properties
Spacecraft4V-1
Spacecraft type4V-1 No. 360[1]
Bus4MV
Launch mass4,447.3 kg (9,805 lb)[1]
BOL mass4,715 kg (10,395 lb)
Landing mass760 kg (1,680 lb)
Dimensions2.7 m × 2.3 m × 5.7 m (8.9 ft × 7.5 ft × 18.7 ft)
Start of mission
Launch dateSeptember 9, 1978 (1978-09-09), 03:25:39 UTC[1]
RocketProton-K/D-1 8K82K
Launch siteBaikonur 81/23
End of mission
Last contactFebruary 1, 1980[1]
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Semi-major axis6,569 kilometers (4,082 mi)
Eccentricity0.0312
Perigee altitude177 kilometers (110 mi)
Apogee altitude205 kilometers (127 mi)
Inclination51.5°
Flyby of Venus
Spacecraft componentVenera 11 flight platform
Closest approach25 December 1978
Distance~35,000 kilometers (22,000 mi)
Venus lander
Spacecraft componentVenera 11 descent craft
Landing date25 December 1978, 03:24
Landing site14°S 299°E / 14°S 299°E / -14; 299 (near Phoebe Regio)

The Venera 11 (Russian: Венера-11 meaning Venus 11) was a Soviet uncrewed space mission which was part of the Venera program to explore the planet Venus. Venera 11 was launched on 9 September 1978 at 03:25:39 UTC.[2]

Separating from its flight platform on December 23, 1978 the lander entered the Venus atmosphere two days later on December 25 at 11.2 km/s. During the descent, it employed aerodynamic braking followed by parachute braking and ending with atmospheric braking. It made a soft landing on the surface at 06:24 Moscow Time (03:24 UT) on 25 December after a descent time of approximately 1 hour. The touchdown speed was 7 to 8 m/s.[3] Information was transmitted to the flight platform for retransmittal to Еarth until it moved out of range 95 minutes after touchdown.[4] Landing coordinates are 14°S 299°E / 14°S 299°E / -14; 299.[3][5]

  1. ^ a b c d Siddiqi, Asif A. (2018). Beyond Earth: A Chronicle of Deep Space Exploration, 1958–2016 (PDF). The NASA history series (second ed.). Washington, DC: NASA History Program Office. pp. 127–128. ISBN 978-1-62683-042-4. LCCN 2017059404. SP2018-4041.
  2. ^ "Venera 11". Archived from the original on 2015-01-21. Retrieved 2012-12-10.
  3. ^ a b "Venera 11 Descent Craft Launch and Orbital Information". NASA Space Science Data Coordinated Archive. Retrieved November 6, 2019.
  4. ^ Cite error: The named reference NSSDC-VDC was invoked but never defined (see the help page).
  5. ^ "Venera 11 – Detail". Archived from the original on 2019-11-09. Retrieved 2012-12-10.