Venus

Venus

Venus is the second planet from the Sun. Venus is a terrestrial planet, and has a mineral composition similar to that of Earth. It is sometimes referred to as Earth's "sister" planet because the similarity between size, gravity, and mineral composition. Both have a liquid metal core, a mantle, and a crust. However that is as far as the similarities go.

Venus's atmosphere is nearly one hundred times thicker than Earth's, and is mostly composed of carbon dioxide, a greenhouse gas. Consequently, the pressure is immense and the temperature on the surface of Venus is over 400°C. Thick, reflective clouds of sulfuric acid engulf the planet, preventing light from reaching the surface. Ironically, if Venus had the same atmosphere as Earth, it would be cooler even though it is closer to the sun. This is because it has a higher albedo than Earth; its surface is more reflective.

Long ago, Venus was strikingly similar to the early Earth. It is possible that it even had Earth-like oceans. However, due to its proximity to the Sun, the oceans started evaporating, adding more water vapor as a greenhouse gas. When it was so hot rain no longer reached the surface, carbon dioxide was no longer washed out of the atmosphere, but volcanoes still kept erupting more, further increasing the greenhouse effect.

The reason that plate tectonics ended on Venus is part because the rock dried completely so that it was no longer lubricated, and part because the heat made the plates themselves elastic and sticky.

Terraforming

Main article: Terraforming of Venus

Ultimately, in order to terraform Venus, the dense carbon dioxide atmosphere will have to be eliminated, and an ocean of liquid water must be created. It would also be a good idea to restart plate tectonics and the carbon-cycle. All of these things are beyond modern technology.

Colonization

Main article: Colonization of Venus

Of course, if Venus were terraformed, colonizing the planet would be easy. However, it is impossible at our current technological level. However, we could still colonize the planet without terraforming it. Venus's atmosphere is so thick that large cities could float on the clouds. However, before we can do this, we must come up with a material that is resistant to the highly corrosive sulfuric acid in the atmosphere. Such materials are already invented, though still expensive.