Venus
Planet
Facts
- Diameter
- 12,104 km
- Mean distance from the Sun
- 108.2 million km
- Orbital period
- 224.7 days
- Rotation
- 243 days, backwards
- Mean temperature
- 464 °C
- Surface pressure
- 92 times Earth's
Venus is the second planet from the Sun, almost as big as Earth and wrapped in thick clouds of sulphuric acid. After the Sun and the Moon it is the brightest object in the sky, and it is named after the Roman goddess of love and beauty.
It spins in the opposite direction to most planets, and so slowly that a day lasts 243 Earth days, longer than its year. The surface is hot enough to melt lead: the dense atmosphere traps heat in a runaway greenhouse effect, and presses down on the ground as hard as water more than 900 metres deep on Earth (about 92 bar).
Between 1961 and 1984 the Soviet Union sent the probes of the Venera programme to Venus. NASA's Magellan spacecraft mapped its surface with radar during a five-year mission that ended in 1994.