Laboratory experiments have uncovered evidence that Venus may still be volcanically active.
Earth is the only planet in the solar system with active volcanoes (if we talk about moons, however, Io, a moon of Jupiter, is also quite volcanically active). And does Venus still have active volcanoes?
Venus Express is a spacecraft that orbited the planet Venus from 2006 to 2014. During its mission it managed to acquire a lot of data, but directly observing any volcanic activity on the surface was practically impossible. The reason? Venus' atmosphere is very, very dense.
A new laboratory experiment enhanced one of the observations made by Venus Express. The data collected could only be explained by a particular volcanic activity connected to a greenish rock called olivine.
How old are the active volcanoes on Venus?
Previously, scientists had found evidence of volcanoes and lava flows on the surface of Venus, but could not figure out the age of these flows.
In general, scientists study the composition of a planet's surface based on the different wavelengths of the light it emits and reflects.
However, the case of Venus is different. Researchers have fewer emission lines to work with because of the carbon dioxide that absorbs part of the light.
Full characterization of the minerals on the surface of Venus requires computer simulations. The evidence serves to understand how chemical reactions and the gaseous atmosphere interacting with surface minerals after an eruption can affect the signals observed by Venus Express.
A previously published study by the same authors focused on olivine, a mineral believed to exist on the surface of Venus. Scientists measured its characteristics including the amount and wavelengths of light reflected after it was oxidized in a blast furnace at 600 and 900 degrees Celsius.
After a month of oxidation, the olivine developed a rusty layer of hematite, changing the wavelengths of the reflected light.
This is important because the Venus Express results seemed to register the signature of the olivine, according to the article published last week in Science Advances.
But if the olivine quickly oxidizes under the warm Venusian atmosphere, then the olivine observed by Venus Express may be only a few months old.
Volcanoes may have brought olivine to the planet's surface a few days before the Venus Express observations. This evidence, combined with occasional spikes in atmospheric sulfur dioxide recorded by both Venus Express and Pioneer Venus Orbiter, almost constitutes a certification that there are still active volcanoes on Venus.
This research is not direct evidence of volcanism on the planet's surface, of course. But it amply justifies a new mission on Venus, this neighbor of ours so reserved as in the past it would have hosted life before a planetary catastrophe.
Volcanoes still active on Venus? He is certainly able to give us the answer.