Venera 5 (russian: Венера-5 meaning ''Venus 5'') was a space probe in the

Soviet space program The Soviet space program (russian: Космическая программа СССР, Kosmicheskaya programma SSSR) was the national space program of the former Union of Soviet Socialist Republics (USSR), active from 1955 until the dissoluti ...

''Venera'' for the exploration 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 ...

. Venera 5 was launched towards Venus to obtain atmospheric data. The spacecraft was very similar to Venera 4 although it was of a stronger design. The launch was conducted using a Molniya-M rocket, flying from the Baikonur Cosmodrome. When the atmosphere of Venus was approached, a capsule weighing and containing scientific instruments was jettisoned from the main spacecraft. During satellite descent towards the surface of Venus, a parachute opened to slow the rate of descent. For 53 minutes on 16 May 1969, while the capsule was suspended from the parachute, data from the Venusian atmosphere were returned. It landed at . The spacecraft also carried a medallion bearing the State Coat of Arms of the Soviet Union and a bas-relief of

Lenin Vladimir Ilyich Ulyanov. ( 1870 – 21 January 1924), better known as Vladimir Lenin,. was a Russian revolutionary, politician, and political theorist. He served as the first and founding head of government of Soviet Russia from 1917 to 1 ...

to the night side of Venus. Given the results from Venera 4, the Venera 5 and Venera 6 landers contained new chemical analysis experiments tuned to provide more precise measurements of the atmosphere's components. Knowing the atmosphere was extremely dense, the parachutes were also made smaller so the capsule would reach its full crush depth before running out of power (as Venera 4 had done).

Instruments

Spaceship

* Instrument KS-18-3M to study the flows of cosmic particles; * Instrument LA-2U to determine the distribution of

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements ...

and

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-to ...

in the planet's atmosphere.

Lander

* Pressure sensors MDDA A to measure atmospheric pressure in the range of 100 to 30,000 mm Hg. Art. (0.13–40 atm); * G-8 gas analyzers to determine the chemical composition of the atmosphere; * TTI unit to determine the density of the atmosphere at an altitude; * FD-69 for atmospheric lighting measurements; * CE-164D to determine the temperature at the height of the atmosphere.

Mission

Venera 5 was launched into an

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's sur ...

parking orbit on 5 January 1969 at 06:28:08 UT and then from a Tyazheliy Sputnik (69-001C) towards

. After a mid-course maneuver on 14 March 1969, the probe was released from the bus on 16 May 1969 at a distance of from Venus. The probe entered the nightside atmosphere at 06:01 UT and when the velocity slowed to 210 m/s the parachute deployed and transmissions to Earth began. The probe sent read-outs every 45 seconds for 53 minutes before finally succumbing to the temperature and pressure at roughly , 26.1 bar. The

photometer A photometer is an instrument that measures the strength of electromagnetic radiation in the range from ultraviolet to infrared and including the visible spectrum. Most photometers convert light into an electric current using a photoresistor, ...

detected a light level of 250 watts per square meter and confirmed the high temperatures,

pressure Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country a ...

s, and

carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...

composition of the atmosphere found by Venera 4.

References

External links