Planet Venus

Known as our sister planet, Venus is similar to Earth in many ways, but dissimilar in many more. Called the Evening Star or the Morning Star depending on when she is viewed, Venus—the only one of the planets given a female name—is the brightest natural object in the night sky outside of the Moon.

A Look at Venus

There are many, many fascinating things to learn about our closest planetary neighbour, the terrestrial (meaning rock based as opposed to gaseous) planet that defies examination by the naked eye thanks to its dense, seemingly impenetrable atmosphere. Venus, named after the Roman goddess of love, has always been a romantic figure in the sky, causing poets and scientists alike to wonder if there was life to be found under the swirling clouds that encased it.

On December 14, 1962, the mystery was solved upon examination of the planet by Mariner 2, a US launched space probe that reported that the surface of the planet was very hot, breaking 400 degrees Celsius, putting to rest any last hope of finding civilization under the clouds. What scientists did find, however, was incredibly fascinating. Over the decades more and more has been learned about Venus. The fact that the planet has an atmosphere and is only slightly smaller than Earth inspired naming it our sister-planet, but the similarities divert sharply from there.

A Dry Planet

Modelling has determined that the surface of Venus would behave similarly to Earth, if it has oceans. Without the lubrication of the great waters, however, there is no movement of tectonic plates. This has lead to some very interesting divergences from Earth. Without tectonic plate movement, the crust of Venus does not recycle at the rate of Earth—Earth’s surface is about 100 million years old, but the surface of Venus is 500 million. Without erosion and plate movement, this means that the impact craters and volcanoes on the surface are in pristine condition. While there are thousands more volcanoes- including over 100 that are the size of Earth’s biggest volcanic island, Hawaii, there are surprisingly fewer craters.

This has lead scientists to surmise that the lack of tectonic plates keeps heat trapped in the planet, and that when it reaches a certain point the entire surface crumbles and is subducted and replaced, which happened 500 million years ago.

Lots of Atmosphere, No Air to Breathe

The atmosphere of Venus is very thick and comprised almost completely of carbon dioxide. While the winds move relatively slowly at only a few miles per hour, the thickness of the atmosphere exerts a good deal of pressure on the surface. It has been surmised that long ago there may have been oceans on the surface, but due to the greenhouse gasses of the atmosphere they have evaporated away.

Final Thoughts

The Venus Express Probe, launched by the European Space Agency in 2005, is currently in orbit around Venus, collecting data. NASA’s MESSENGER probe conducted two fly bys of Venus on its way to Mercury, also collecting data. In 2013 NASA is planning on landing a probe on the surface for more investigation. Soon we will know much more about our sister in the sky.