Venus
is 108 million km. from the Sun.
It is often called Earth's twin or sister because
it is almost the same size as Earth.
But Venus is not at all like the Earth.
Venus orbits the Sun in 225 Earth days and rotates on its axis
every 243 Earth days.
This slow rotation means that one Venusian day is
like 243 days on Earth.
Venus rotates from east to west,
while Earth rotates from west to east.
Venus taken by the spacecraft Galileo 1990
Venus is surrounded by thick clouds which are not composed of water droplets,
but are composed of droplets of sulfuric acid.
The poisonous atmosphere is mostly carbon dioxide gas.
The clouds move at high speeds.
Bolts of lightning streak across the sky.
The planet has no water and is covered
with volcanoes and old lava flows.
It is hotter on Venus than it is on Mercury,
even though Mercury is closer to the Sun.
This happens because the clouds lets some sunlight in
and trap heat against the planet's surface (greenhouse effect).
Temperatures on Venus are high enough to melt metals.
A radar image of Venus collected by the Magellan spacecraft
in 1992 ( Courtesy of NASA)
The Magellan Spacecraft launched in 1989
took 15 months to reach Venus. It orbitted the planet from
1990 to 1994 mapping the surface of Venus.
Another spacecraft the Venus Express is a mission of the ESA (European Space Agency).
It was launched in 2005 and reached Venus in April 2006. It will study the planet's atmosphere and
clouds. The mission ends in December 2009.
Venus Express spacecraft (credits : ESA/C.Carreau)
Venus was named after the Roman Goddess of Love and Beauty.
It is also known as the "morning star"
(because at sunrise it appears in the east) and
the "evening star" (it appears at sunset when it is in the west).
Venus cannot be seen in the middle of the night.
Except for the Sun and the Moon, Venus is the brightest object in the sky.
Venus has no moon.
