Venera 2MV-2 No.1, also known as Sputnik 21 in the West, was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...

spacecraft, which was launched in 1962 as part of the

Venera The Venera (, , which means "Venus" in Russian) program was the name given to a series of space probes developed by the Soviet Union between 1961 and 1984 to gather information about the planet Venus. Ten probes successfully landed on the s ...

programme, and was intended to make a flyby of

Venus Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never f ...

. Due to a problem with the rocket which launched it, it failed to leave

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...

, and reentered the atmosphere a few days later. It was the second Venera 2MV-2 spacecraft, both of which failed to leave Earth orbit.

Launch

Venera 2MV-2 No.1 was launched at 00:59:13 UTC on 12 September 1962, atop a Molniya 8K78 carrier rocket flying from Site 1/5 at the Baikonur Cosmodrome. The rocket performed nominally until cutoff of the Blok I stage, following injection into a

. Following cutoff, one of the oxidiser valves failed to close, and

liquid oxygen Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an app ...

was allowed to flow into the combustion chamber of one of the

vernier thruster A vernier thruster is a rocket engine used on a spacecraft for fine adjustments to the attitude or velocity of a spacecraft. Depending on the design of a craft's maneuvering and stability systems, it may simply be a smaller thruster complementin ...

s. The vernier thruster exploded, causing the rocket to tumble out of control. This led to the formation of bubbles in the upper stage oxidiser pump, which caused the upper stage engine to fail less than a second after ignition. It reentered the atmosphere on 14 September 1962, two days after it had been launched.

Spacecraft designation

The designations Sputnik 25, and later Sputnik 21, were used by the United States

Naval Space Command The Naval Space Command (NSC) was a military command of the United States Navy and former component command of United States Space Command. It was headquartered at Dahlgren, Virginia, and began operations on 1 October 1983. Naval Space Command us ...

to identify the spacecraft in its Satellite Situation Summary documents, since the Soviet Union did not release the internal designations of its spacecraft at that time, and had not assigned it an official name due to its failure to depart

geocentric orbit A geocentric orbit or Earth orbit involves any object orbiting Earth, such as the Moon or artificial satellites. In 1997, NASA estimated there were approximately 2,465 artificial satellite payloads orbiting Earth and 6,216 pieces of space debri ...

References

1962 in the Soviet Union Spacecraft launched in 1962 Venera program Spacecraft which reentered in 1962 {{USSR-spacecraft-stub

Launch

Spacecraft designation

See also

References