World Library  
Flag as Inappropriate
Email this Article

Venera 11

Article Id: WHEBN0000599926
Reproduction Date:

Title: Venera 11  
Author: World Heritage Encyclopedia
Language: English
Subject: Venera, Venus, Venera 12, Venera 9, Venera 6
Collection: 1978 in Spaceflight, 1978 in the Soviet Union, Derelict Landers (Spacecraft), Missions to Venus, Spacecraft Launched in 1978, Venera Program
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Venera 11

Venera 11
Operator USSR
Mission type Flyby and Lander
Launch date 9 September 1978 at 3:25:39 UTC
Launch vehicle Proton Booster Plus Upper Stage and Escape Stages
Flyby date December 25, 1978
Satellite of Venus
COSPAR ID 1978-084D
Mass 4940 kg
Orbital elements
Periapsis 6.62 RV (flight platform)

The Venera 11 (Russian: Венера-11 meaning Venus 11) was a USSR unmanned space mission part of the Venera program to explore the planet Venus. Venera 11 was launched on 9 September 1978 at 3:25:39 UTC.[1]

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 (0324 UT) on 25 December after a descent time of approximately 1 hour. The touchdown speed was 7 to 8 m/s. Information was transmitted to the flight platform for retransmittal to earth until it moved out of range 95 minutes after touchdown.[2] Landing coordinates are .[3]

Contents

  • Flight platform 1
  • Lander 2
  • See also 3
  • References 4
  • External links 5

Flight platform

After ejection of the lander probe, the flight platform continued on past Venus in a heliocentric orbit. Near encounter with Venus occurred on December 25, 1978, at approximately 34,000 km altitude. The flight platform acted as a data relay for the descent craft for 95 minutes until it flew out of range and returned its own measurements on interplanetary space.[4]

Venera 11 flight platform carried solar wind detectors, ionosphere electron instruments and two gamma ray burst detectors – the Soviet-built KONUS and the French-built SIGNE 2. The SIGNE 2 detectors were simultaneously flown on Venera 12 and Prognoz 7 to allow triangulation of gamma ray sources. Before and after Venus flyby, Venera 11 and Venera 12 yielded detailed time-profiles for 143 gamma-ray bursts, resulting in the first ever catalog of such events. The last gamma-ray burst reported by Venera 11 occurred on January 27, 1980

List of flight platform instruments and experiments:[5]

  • 30–166 nm Extreme UV Spectrometer
  • Compound Plasma Spectrometer
  • KONUS Gamma-Ray Burst Detector
  • SNEG Gamma-Ray Burst Detector
  • Magnetometer
  • 4 Semiconductor Counters
  • 2 Gas-Discharge Counters
  • 4 Scintillation Counters
  • Hemispherical Proton Telescope

The mission ended in February, 1980.

Lander

The lander carried instruments to study the temperature and atmospheric and soil chemical composition. A device called Groza detected lightning on Venus. Both Venera 11 and Venera 12 had landers with two cameras, each designed for color imaging, though Soviet literature does not mention them. Each failed to return images when the lens covers did not separate after landing due to a design flaw. The soil analyzer also failed. A gas chromatograph was on board to measure the composition of the Venus atmosphere, as well as instruments to study scattered solar radiation. Results reported included evidence of lightning and thunder, a high Ar36/Ar40 ratio, and the discovery of carbon monoxide at low altitudes.[2]

List of lander experiments and instruments:

  • Backscatter Nephelometer
  • Mass Spectrometer – MKh-6411
  • Gas Chromatograph – Sigma
  • X-Ray Fluorospectrometer
  • 360° Scanning Photometer – IOAV
  • Spectrometer (430–1170 nm)
  • Microphone/Anemometer
  • Low-Frequency Radio Sensor
  • 4 Thermometers
  • 3 Barometers
  • Accelerometer – Bizon
  • Penetrometer – PrOP-V
  • Soil Analysis Device
  • 2 Color Cameras
  • Small solar batteries – MSB

See also

References

  1. ^ "Venera 11". 
  2. ^ a b "Venera 11 Descent Craft". 
  3. ^ "Venera 11 – Detail". 
  4. ^ "Venera 11 (NASA NSS-DC)". 
  5. ^ Mitchell, Don P. "Drilling into the Surface of Venus". Retrieved 13 April 2013. 

External links

  • Venera 11 & Venera 12 (NASA)
  • Experiments on Venera 11 (NASA NSS-DC) Has detail on each experiment/instrument.
  • Drilling into the Surface of Venus (Venera 11 and 12)
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.