Venera 4 - Credit: NASA. 16,024 bytes. 338 x 217 pixels.

Venus probe with the announced mission of direct atmospheric studies. The descent vehicle carried two thermometers, a barometer, a radio altimeter, an atmospheric density gauge, 11 gas analyzers, and two radio transmitters operating in the DM waveband. The main bus, which carried the capsule to Venus, had a magnetometer, cosmic ray detectors, hydrogen and oxygen indicators, and charged particle traps. Signals were returned by the spacecraft, which braked and then deployed a parachute system after entering the Venusian atmosphere, until it reached an altitude of 24.96 km.

Total Mass: 1,105 kg.

Venera 4 was successfully launched towards the planet Venus with the announced mission of direct atmospheric studies. On October 18, 1967, the descent vehicle entered the Venusian atmosphere. Signals were returned by the spacecraft, which deployed a parachute after braking to subsonic velocity in the Venusian atmosphere, until it reached an altitude of 24.96 km.

Suggestions for the cause of the failure included incorrect soldering of wires in multiple pin plugs, wrong attachments of the plugs to the pyrotechnic connectors, or a mix-up of the pyrotechnic connectors during assembly.. Investigation of the upper atmosphere and outer space.

• 2 - McDowell, Jonathan, The United Nations Registry of Space Objects, Harvard University, 1997. HTML when accessed: http://hea-www.harvard.edu/QEDT/jcm/space/un/un.html
• 6 - JPL Mission and Spacecraft Library, Jet Propulsion Laboratory, 1997. HTML when accessed: http://msl.jpl.nasa.gov/home.html
• 64 - Varfolomyev, Timothy, Spaceflight, "Soviet Rocketry that Conquered Space - Part 5", 1998, Volume 40, page 85.
• 65 - Novosti Kosmonavtiki, "Otmenenniy Start "Molniya-M"", 1997, Issue 1, page 29.
• 296 - National Space Science Center Planetary Page, As of 19 February 1999.. HTML when accessed: http://nssdc.gsfc.nasa.gov/planetary/planetary_home.html