Atmosphere
The atmosphere on Venus
is quite a harsh enviroment. On the surface the pressure is 90 atmospheres.
This is equivalent to the pressure at a depth of 1 km in Earth's oceans.
The atmosphere is composed or roughly 96% carbon dioxide and 3% nitrogen.
The planet is covered by several layers of clouds
many km thick. These clouds are composed of Sulfuric Acid and prevent us
from seeing the surface of the planet except through the use of radar. The
dense atmosphere also leads to the trapping of heat. In other words the
atmosphere produces a run-away greenhouse effect that raises Venus's
surface temperature by about 400 degrees to over 740° K. This temperature
is hot enough to melt lead. This greenhouse effect leads to surface temperatures
on Venus that are hotter than Mercury despite the fact that Venus is about
twice as far away from the Sun. A final interesting point about Venus's
atmosphere would be the strong winds that are experienced at the cloud tops.
At the tops of the clouds the wind howls along at 350 kph. However at the
surface the winds are much slower, most likely not faster than a few kilometers
per hour.
