Volcanoes on Venus? New Clues, and Mysteries, About Earth’s Boiling Twin

The evidence: A sharp decline in detected sulfur dioxide on the surface of Venus. The culprit: A volcanic eruption, caught in the act?

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SSPL / Getty Images

A volcano named Sapas Mons dominates this computer-generated view of the surface of Venus. Lava flows extend for hundreds of kilometers across the fractured plains shown in the foreground to the base of the mountain, which measures 248 miles (400 km) across and 0.9 mile (1.4 km) high.

It’s got to be frustrating for planetary scientists that the world closest to Earth and most similar in size as well—so similar that it’s often described as our planet’s twin—is in many ways the toughest to study. Venus’ perpetual shroud of thick, opaque clouds makes it impossible to see the surface with even the most powerful telescopes, and its sweltering surface temperature (think 900°F) makes it impossible for landers to survive for more than a few minutes.

Nevertheless, orbiting spacecraft armed with radar and other instruments have taught scientists quite a lot about Venus’ atmosphere over the years, and even its surface—and a new study in Nature Geoscience is now reporting another, intriguing piece of information. The European Space Agency’s Venus Express has detected a sharp decline in sulfur dioxide (SO2) concentrations in the planet’s atmosphere following a spike in SO2 just after the probe arrived in 2006. The most plausible explanation, says lead author Emmanuel Marcq, is a volcanic eruption, caught in the act.

(PHOTOS: The Transit of Venus: Photographs from a Rare Celestial Event)

It’s not the only possible explanation, he admits. “We know that on Earth there are long-term atmospheric cycles, so it could happen on Venus as well. We can’t dismiss this possibility at the moment.”

Volcanoes, however, are a lot more likely. One reason is that they’re known sources of SO2, at least on Earth. Another is that Venus is peppered with them — hundreds upon hundreds of volcanic mountains, lava flows and other features that make the planet’s history of volcanism unmistakable. Most of them appear to be long dead, but there have been hints in the past that a few might still be active. In the early 1990’s for example, radar on the Magellan spacecraft detected what appeared to be fresh lava, and back in the early 1980’s Pioneer Venus documented SO2 levels nearly 50 times higher than anyone expected, followed by a steady dramatic decline. “It’s very similar,” he says, “to the one we’re observing now.”

If a volcano really did erupt just after Venus Express showed up, the event could have been seen directly by the satellite’s infrared detectors — but only on the planet’s night side, since average daytime temperatures are so high that an extra hotspot wouldn’t stand out very easily. And even so, the orbiter only passes over a given spot on the Venusian surface every 100 days. “It’s unlikely,” says Marcq, “that we would be able catch an eruption.”

(WATCH: Why You Should Be Really, Really Glad You Don’t Live On Venus)

It’s also highly unlikely that this eruption, or any conceivable eruption on Venus, could do much to make the planet more hospitable. When a big volcano goes off on Earth — Krakatoa, for example, or even the more modest Pinatubo — its sulfur dioxide output forms light-reflecting particles high in the stratosphere that bounce sunlight back into space and temporarily cool the planet. Indeed, volcanic eruptions are one of the natural forces that climate scientists take into account when trying to discern the fingerprint of manmade climate change.

On Venus, however, the carbon-dioxide-rich atmosphere has created a runaway greenhouse effect and global warming beyond anyone’s worst nightmares. This recent eruption could cool the planet – but only by a few degrees. When you’re talking temperatures that are already hot enough to melt lead, a few degrees of relief isn’t going to make a whole lot of difference for vulnerable rovers – or astronauts.

PHOTOS: Window on Infinity: Pictures from Space
MORE: The Transit of Venus: 2012 Gets Another Celestial Showstopper


I really believe we are limited by our own biology. We keep insisting that water is essential for life. We only believe this because we are yet to discover otherwise. So until we do, we wre limited in our searching.

PS - we are all originally from Mars. We destroyed that planet and moved on to earth.....but I have no proof...


there was a massive eruption or collision on Venus back in May of 2012....


It's time for genetic engineers to see what they can do as terraformers. They could try to adapt organisms, like those heat resistant ones found near volcanic vents, into neutralizing Venus's atmospheric acid. Getting rid of those acidic clouds seems like the first step to me. Machinery won't do it, so biology must. Engineered for rapid generations, such an organism could show a planet-wide effect in mere decades.


I agree jaareshiah, Earth is unique.  One in a million IS unique, but our galaxy alone contains trillions upon trillions of stars with countless planets orbiting them.  This makes Earth, and millions of other planets, unique but not alone by any means.  It would appear your God(s) has been very busy "designing".  Me thinkst thou dost anthropomorphize too much.


This proves a point, that the earth is unique in the universe, able to not only sustain life, but make it enjoyable. The earth was not an accident in the cosmos, but an intentional creation of a Master Designer. Within the Bible is found his name, Jehovah.(Ps 83:18) He purposefully made the earth full of life, of such variety as to stagger the imagination.(Ps 104:24, 25)

He precisely placed the earth within our Milky Way galaxy, with our solar system some 28,000 light years from the center, and being called the galactic hospitable zone by many scientists, where it is just the right concentration of chemical elements needed to support life. And within our solar system, he exactly placed the earth just right distance from the sun, being called the circumstellar habitable zone, where life neither freezes nor fries.

Venus, on the other hand, fries anything placed on it, with 900 degrees F. and of Mars, it may have some water, but it remains frozen on the Martian poles, with temperatures dropping as low as -225 degrees F. at the poles. Thus, the earth is not only the right distance from the sun, but also the right size, for if it were slightly smaller, with a weaker gravitational field, life sustaining oxygen and surface water would escape, and eventually our planet would be barren from the loss of all water. If it were larger, it would have a slightly stronger gravitational field and therefore hydrogen, a light gas, could not escape into space, building up and eventually rendering our planet inhospitable.