April 11, 2006
Europe’s Venus Space Probe Enters Orbit
DARMSTADT, Germany -- Europe's first space probe to Venus entered the planet's orbit on Tuesday and sent its first transmissions from there to Earth, ground controllers said.
Officials at the European Space Agency's Space Operations Center in Darmstadt, Germany, said the Venus Express probe had completed a braking operation shortly after 0800 GMT to gain position to be dragged into the planet's orbit.After a brief so-called occultation period when the craft passed behind the planet and out of contact with Earth, transmissions were received at 0912 GMT, according to the Agency's Web site www.esa.int.
Scientists will use the data transmitted from the planet's scorching greenhouse atmosphere to look for answers as to why a planet so similar to Earth in size, mass and composition has evolved so differently over the last 4,600 million years.
Temperatures on Venus average 450 degrees Celsius (842 degrees Fahrenheit) and the planet is covered with a dense layer of clouds some 20 km (12 miles) thick.
Venus Express is a virtual twin of the Mars Express craft which has been providing spectacular images of the Red Planet since 2003.
The 1.3 ton craft took off on a Russian Soyuz rocket from Baikonur in Kazakhstan last November, traveling 400 million km through space toward a mission scheduled to last for two Venusian days, corresponding to 486 days on Earth.
One Venus day is the equivalent of 243 Earth days, due to its slower rotation.
It will orbit the planet's poles well above the cloud cover from a distance of 250 to 66,000 km, collecting data with instruments designed to build on observations from previous missions to the planet.
There are theories that intense volcanic activity could have created an extreme greenhouse atmosphere that is responsible for the current conditions on Venus, whose atmosphere is mainly composed of carbon dioxide with clouds of sulphuric acid drops.
Some scientists have said there may once have been life on Venus. They hope to obtain clues about greenhouse conditions on Venus and whether any comparisons about global warming on Earth can be drawn.
Atmospheric pressure is 90 times greater than on Earth and no space probe that has gone into the planet's atmosphere has survived for long, with a Russian device setting the record of 110 minutes before melting in the heat.
A total of 25 companies from 14 European countries are involved in the Venus Express, which cost 220 million euros ($266.7 million).