Ancient astronomers named it for the goddess of love and beauty, this object that dominated their night sky. What they could not know was that this bright entity was a world of its own, though there is little that any human would consider familiar on this cloud-shrouded neighbor of Earth's. However Venus has more in common with Earth than most think, as well as a few unique attributes all its own.
Earth's Twin Planet
Though it would be difficult to tell by looking at it, the exceedingly hot, perpetually cloud-covered planet of Venus is known in some science circles as "Earth's twin." It's size so closely corresponds to Earth's own that Earth's diameter is a mere 400 miles greater than Venus's. The two also orbit very closely to each other, astronomically speaking. In fact, no other two planets in the solar system orbit so near each other as do Earth and Venus.
Venus is so close to Earth that it is the brightest object that appears in the night sky, aside from the Sun and the Moon. It outshines the brightest stars and all other planets. It is also amongst the more famous objects in the night sky, being known, as it has been throughout history, as both the Morning and Evening Star.
A Hot, Cloudy Planet
Despite being named for the Roman goddess of love and beauty, there is little loveliness to be found on the scorched desert that is Venus's surface. The average temperature on the ground approaches 900°F, hotter than the planet Mercury. This is because Venus's constant thick cloud layer traps heat in a way the nearly airless Mercury cannot, a phenomenon known as the greenhouse effect.
Fun Venus Facts
Venus's desert surface has many varying features matching those on Earth: canyons, plains, mountains, even old volcanoes. Appropriately, seeing as Venus is named for a goddess, all of its known surface features are named for famous women from history, literature, and mythology. Surface features are mapped through the clouds by radar, both from passing spacecraft and from Earth itself.
Venus has a very unusually shaped orbit – it is nearly a perfect circle. All other planets have slightly elongated, oval-shaped elliptical orbits. Venus takes about 225 Earth days to orbit the Sun, but it only takes about 0.92 Venus days to orbit. That's right, Venus's day is longer than its year. Venus takes about 243 Earth days to rotate once, and it goes backwards, from an Earthling's point of view. If someone standing on the surface could see the Sun through the clouds, it would rise in the West and set in the East.
Visitors to the Planet Venus
A number of spacecraft have visited the planet Venus. It was, in fact, the first planet to be viewed by a passing spacecraft when Mariner 2 shot past in 1962. The most prolific explorations of Venus, however, were undertaken by the Soviet Union, which launched a number of Venera spacecraft missions, some of which actually landed on the planet and sent back pictures of the bleak orange surface. The American spacecraft Magellan orbited the planet for five years in the early 1990s before burning up in the atmosphere.
Currently operating around Venus is the European Space Agency's Venus Express, which launched in 2005 and reached orbit around Venus in 2006. The mission studies both the planet's thick atmosphere, its rugged surface, and its interior, in hopes of adding to the body of knowledge on this, Earth's shrouded twin planet.
Sources:
Dunbar, Brian. "NASA-Venus," NASA, November 29, 2007. Accessed March 3, 2010.
Talia Sepersky - I am a 2008 graduate of Wellesley College, where I earned my Bachelor's in astrophysics. A year later I earned my Master's in science ...
Join the Conversation