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Venus

A view of the surface of Venus beneath its permanent, dense cloud cover. Channels cut by lava flows wind across the surface. The...Read More >>A view of the surface of Venus beneath its permanent, dense cloud cover. Channels cut by lava flows wind across the surface. The dark areas are plains covered with solidified lava. Venus is the second planet from the Sun. About the same size as Earth, Venus is sometimes referred to as our sister planet. But these sisters have very little else in common. In fact, the planet named after the Roman goddess of love is almost certainly the nastiest place in the Solar System. Venus spins slowly on its axis, actually taking longer to complete one rotation than to circle the Sun. By contrast, its clouds race around the planet in just four days. Unlike all the other planets in the Solar System, Venus spins not from west to east, but from east to west. No one knows why it spins “backwards”.



Venus, shrouded in dense cloud

Atmosphere

Venus is shrouded in thick, unbroken clouds. They are made not of water but droplets of deadly sulphuric acid. Some 25 kilometres (15 miles) thick, the clouds prevent most sunlight from reaching the surface. But another kind of radiation from the Sun, infrared, does get through and Venus’s dense carbon dioxide atmosphere stops it from escaping. It is the same “greenhouse effect” as happens on Earth, but much more extreme. The result is a constant surface temperature of 490°C (914°F), the hottest in the Solar System. Even the heavy metal lead would melt in that heat.
Any water that once existed on Venus would have evaporated long ago. If any space explorer landing on Venus could somehow resist the heat, they would be suffocated by the unbreathable carbon dioxide air, dissolved by sulphuric acid and crushed by air pressure about 90 times that on Earth.
 

After the Moon, Venus is the brightest natural object in the night sky. It is bright enough sometimes to be seen in the middle of the day. It is often mistaken for a UFO.

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