Next Stop Venus: Europe's Express Probe Launches Toward Earth's 'Twin'
A Soyuz rocket topped with a Fregat upper stage launches the Venus Express probe into space for the European Space Agency (ESA) on Nov. 8, 2005 EST. It was early morning on Nov. 9 at the probe's Baikonur Cosmodrome, Kazakhstan launch site.
Credit: ESA.

A European probe is bound for the planet Venus on a mission to peel back the shroud of the planet's thick atmosphere after successfully launching into space atop a Russian rocket.

The European Space Agency's (ESA) Venus Express spacecraft rode a Russian-built Soyuz rocket into space at about 10:33 p.m. Nov. 8 EST (0333 Nov. 9 GMT), lifting off from Baikonur Cosmodrome in Kazakhstan on a 162-day trip to the second planet from the Sun.

By 12:13 a.m. EST Wednesday, ESA officials said Venus Express had successfully fired the engine of its Fregat upper stage for a final time, sending the probe on a Venus-bound course. The probe later unfurled its solar arrays, ESA officials said.

"I have great expectations for this mission," Venus Express project scientist H?kan Svedhem told in an e-mail interview before launch. "I am sure we will get very exciting data and perhaps a few surprises."

The $260 million (220 million Euro) Venus Express probe is the ESA's fastest spacecraft to develop to date, taking less than four years to move from the concept phase to launch, and its first aimed at Venus. While several probes have swung past the planet on their way to other bodies in the Solar System, the ESA's Venus Express is the first dedicated probe to investigate the cloudy world since NASA's Magellan orbiter burned up in the planet's atmosphere in 1994.

"The atmosphere of Venus is so alien compared to Earth, yet it's our sister planet," Kevin Baines, a scientist from NASA's Jet Propulsion Laboratory (JPL) participating in the ESA mission, told before launch. "We've got the same size, the same materials basically and almost the same gravity."

But somewhere along the line, Earth's neighbor clouded over with a thick atmosphere rich in carbon dioxide, and a surface temperature of averaging about 869 degrees Fahrenheit (465 degree Celsius). Researchers believe the planet may be example of the greenhouse effect run amok, in which the world's atmosphere traps in heat.

"Venus has a lot of lessons to teach the Earth about how things could go awry," said Baines, who is participating on work with two Venus Express' instruments.

The 2,733-pound (1240-kilogram) probe carries seven high fidelity instruments - many of which leftover or derived from previous tools aboard ESA's Mars Express and Rosetta probes - to make a detailed study of the planet's atmosphere.

While Venus Express' primary goal is to peer close at the Venusian atmosphere, Svedhem and other mission team members are hopeful the spacecraft's instruments may find hints of active volcanoes and other features on the planet's surface.

"We shall get detailed images of the dynamic behavior of the atmosphere in three dimensions and spectra telling us the about the various substances in the atmosphere," Svedhem said. "There are so many things that we want to study on Venus and the spacecraft and the instruments are all in excellent condition."

Tuesday's late-night launch - though it was early morning on Nov. 9 at the mission's Kazakh launch site - marked the second attempt to launch Venus Express.

Launch officials missed an initial Oct. 26 launch date after engineers discovered traces of insulation contamination inside the probe's protective launch fairing. The contamination forced pad workers to remove Venus Express from its Soyuz-Fregat booster to allow cleaning.

"This Soyuz rocket has proven to be very reliable and it has a very good record," Svedhem added.

ESA officials expect Venus Express to enter orbit around its target planet on April 11 of next year. After a series of passes to adjust its orbit, the probe should reach its final flight configuration by about May 7, they added.

Venus Express is slated to spend at least 15 months studying the Venusian atmosphere - which spans about two full days on Venus due to its slow spin rate - though that term could be extended in the future, ESA officials said.