Volcanoes may still be active on Venus

Posted by Emma Woollacott

Venus is still capable of volcanic eruptions, data from ESA’s Venus Express spacecraft suggests.

Relatively young lava flows have been identified by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS), through the way they emit infrared radiation.

It's been clear for a while that volcanic processes have probably been at work  on Venus's surface - there are simply not enough craters on Venus, and something has been wiping them away.

But the new data indicates that this is happening through a gradual sequence of small volcanic eruptions, rather than through some sort of cataclysm.

"Now we have strong evidence right at the surface for recent eruptions," says Sue Smrekar, a scientist at NASA's Jet Propulsion Laboratory in California. 
 
That strong evidence comes in the form of compositional differences compared to the surrounding landscape in three volcanic regions.

Dr Smrekar and her colleagues targeted three regions that geologically resemble Hawaii, well known for its active volcanism. They found that these regions have higher emissivities - the brightness of surface rocks - than their surroundings, indicating different compositions.

They believe that a lack of surface weathering indicates that the flows are relatively recent. They're pretty sure they've erupted in the last two and a half million years, and likely much less - and that they may well even be currently active.

"This is a significant result," says Håkan Svedhem, ESA Venus Express project scientist.