Venus

Venus, second planet from the sun in the solar system. Its diameter is 7,700 mi (12,392 km), slightly smaller than that of the earth. Its face is completely obscured by dense clouds containing sulfuric acid, although the USSR's spaceprobes Venera-9 and Venera-10 (Oct. 1975) landings provided photographs of the planet's rocky surface. Venus revolves about the sun at a mean distance of 67.2 million mi (108.2 million km) in 225 days, rotating on its axis in a retrograde direction in 243 days. Its atmosphere is 97% carbon dioxide, and its surface temperature is c.850°F (455°C). Venus has no known moons and could not support life.

See also: Planet; Solar System.