Spacecraft Spots Active Volcanoes on Venus

Venus is alive.

Researchers using data from the European Space Agency's Venus Express spacecraft said they spotted three active volcanoes that recently poured red hot lava onto the planet's already broiling surface.

The discovery, announced in a paper published Friday online in Science, suggests that Venus - like the Earth - is periodically resurfaced by lava flows, explaining why it seems devoid of craters.

"We estimate the flows to be younger than 2.5 million years, and probably much younger, likely 250,000 years or less, indicating that Venus is actively resurfacing," the authors write. They were led by Suzanne E. Smrekar of the Jet Propulsion Laboratory in Pasadena.

Venus is only slightly smaller than Earth, but it seems to have evolved rather differently. It is swaddled in dense clouds of carbon dioxide. The pressure at the surface is 93 times the atmospheric pressure on Earth, and the temperature is almost 900 degrees Fahrenheit - enough to melt lead.

The planet shows no sign of the plate tectonics, the continental shifts and rumbles that keep the Earth's surface fresh and erase impact craters, but satellite mappers have detected nine so-called hot spots resembling the Hawaiian islands, which are higher and hotter than the surrounding Venusian plains.

The Venus Express examined three of these smoldering humps with its Visible and Infrared Thermal Imaging Spectrometer, or Virtis, which can see through the thick clouds on Venus and measure the brightness of surface rocks.

The humps range from about half a mile to a mile high. Rocks in these regions, known as Imdr Regio, Dione Regio and Themis Regio, were anomalously bright compared with their surroundings, suggesting that they were relatively young and unweathered by the corrosive Venusian environment.