Venus is the second planet from the Sun and the sixth largest Orbit: Diameter: Mass: 108,200,000 km (0.72 AU) from the Sun 12,103.6 km. 4.869e24 kg

Astronomy

Venus was well known in antiquity. It is the brightest object in the sky except for the Sun and the Moon. Venus is never more than 48 degrees away from the Sun when viewed from the Earth. Since Venus orbits closer to the Sun than Earth does, it shows phases when viewed with a telescope from the Earth. Galileo's observation of this phenomenon was important evidence in favor of the Copernican heliocentric theory of the solar system.

The rotation of Venus is somewhat unusual in that it is both very slow, 243 Earth days per Venus day, and slightly longer than a Venusian year. Venus spins in the opposite direction to most of the other planets. In addition, the periods of Venus' rotation and of its orbit are synchronized so that they always present the same face toward Earth when the two planets are at their closest approach. Whether this is a resonance effect or merely a coincidence is not known.

Venus is sometimes regarded as Earth's sister planet. However, a more detailed study of Venus reveals that in many important ways it is radically different from Earth. To begin with, temperature on Earth varies depending on place and season. However, there is no way to escape the heat on Venus, where a searing 460 degrees (860F) is maintained day and night. This is hot enough to melt lead and zinc. The atmospheric pressure at the surface of Venus is 90 times greater than on Earth, approximately equivalent to the pressure at a depth of 1 km in the Earth's oceans. The atmosphere is composed mostly of carbon dioxide which traps solar energy and heats up Venus in much the same way as a thick blankets serve to keep us warm at night. Thick clouds of sulfuric acid obscure our view of the surface of Venus and produce acid rain. The result is a greenhouse effect gone wild. Venus probably once had large amounts of water like Earth which all boiled away.

Venus has no magnetic field, perhaps because of its slow rotation, and no satellites, but its atmosphere extends in a large tail (like a comet) away from the sun. Venus is usually visible to the naked eye. Because Venus orbits near the Sun, it always appears as a dazzling object just after the Sun sets and just before it rises. This is why people often refer to it (inaccurately) as the "morning star" or the "evening star". though it is almost certainly the planet Venus, outshining every other star and planet because its thick clouds reflect the Sun's light.

If you would like to know more about the solar system, Starscine suggests the following websites:

www.nineplanets.org
www.nasa.gov