Venus is the second planet from the Sun, orbiting it every 224.7 Earth Days. It has no natural satelite. It is named after the Roman goddess of Love and Beauty. After the Moon, it is the brightest natural object in the night sky, reahing an apparent magnitude of -4.6, bright enough to cast shadows.
Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8º.
Venus is a terrestrial planet and is sometimes called Earth's "sister planet" because of the similar size, mass proximity to the Sun and bulk composition. It is radically different from Earth in other respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide.
The atmospheric pressure at the planet's surface is 92 times that of Earth's. With a mean surface temperature of 735 K (462ºC; 863ºF), Venus is by far the hottest planet in the Solar System, even though Mercury is closer to the Sun.
Venus has no carbon cycle that puts carbon into rock, nor does it seem to have any organic life to absorb in biomass. Venus is shrouded by an opaque layer of highly reflective clouds of sulfuric acid, preventing it's surface from being seen from space in visible light.
It may have possessed oceans in the past, but these would have vaporized as the temperature rose due to a runaway greenhouse effect. The water has most probably photodissociated, and because of lack of a planetary magnetic field, the free hydrogen has been swept into interplanetary space by the solar wind.
Venus' surface is a dry desertscape interpersed with slab-like rocks and periodically refreshed by volcanism.
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