Probe photographs Venus' south pole


European mission will study greenhouse effect

Thursday, April 13, 2006 Posted: 1559 GMT (2359 HKT)

A false color image of Venus' south pole captured by the Venus Express probe.

BERLIN, Germany (AP) -- A photo of the south pole of Venus taken by the Venus Express spacecraft was released Thursday -- revealing a twist of cloud swirling around the far end of Earth's neighbor that closely resembles cloud formations around the more familiar north pole.

The image, taken from a distance of roughly 200,000 kilometers (124,000 miles) and released by the Max Planck institute in Germany, is grainy, but shows pale yellow clouds ribbed with darker spirals.

It was taken by a camera run by the institute that is one of seven instruments aboard the European Space Agency's Venus Express, which went into orbit around the planet Monday. (Full story (

The space agency will use the spacecraft's instruments to search for clues about why Venus wound up with an atmosphere almost 90 times denser than Earth's and shrouded in clouds of sulfuric acid.

Of key importance will be studying Venus' strong greenhouse effect -- the way carbon dioxide traps the sun's heat -- and the permanent hurricane force winds that constantly circle it high in the atmosphere.

The instruments on board the $260 million craft include spectrometers to measure temperature and analyze the atmosphere and a special camera that will concentrate on documenting whether Venus' many volcanoes are active.

Venus is the nearest planet to Earth within the solar system, and the two have similar mass and density. Both have inner cores of rock and are believed to have been formed at roughly the same time.

Yet despite those similarities, the two have vastly different atmospheres, with Venus' composed almost entirely of carbon dioxide and very little water vapor. Thanks to runaway warming from its greenhouse effect, Venus has the hottest surface of all the planets.

If everything goes according to plan, the European agency plans to keep the probe active for 500 days, with the possibility of extending its life by another 500 days.

The probe, coated with a metallic polymer skin to protect it from heat, is a sister craft to ESA's Mars Express, which was launched in June 2003 and reached Martian orbit in December of that year.

Venus Express was launched November 9 atop a Russian booster rocket from the Baikonur Cosmodrome in Kazakhstan.

The last mission to Venus was NASA'S Magellan probe, launched in 1989. It completed more than 15,000 orbits between 1990 and 1994, and mapped almost all of Venus, revealing towering volcanoes, gigantic rifts and sharp-edged craters.