Life on Venus – Why Not?

April 17, 2018

Venus shouldn’t be dismissed as a possible abode for life, some scientists stress.

Sure, the planet’s surface is famously inhospitable today — bone-dry and hot enough to melt lead, with an atmospheric pressure 90 times greater than that of Earth at sea level. To feel that same amount of squeeze on our planet, you’d have to descend about 3,000 feet (900 meters) into the oceans.

But Venus was a temperate world long ago, with seas that persisted for eons — perhaps 2 billion years or more, according to recent modeling research.

Venus may therefore have been a habitable planet “for much of solar system history,” astrobiologist David Grinspoon, a senior scientist at the Planetary Science Institute in Tucson, Arizona, said Thursday (April 12) during a talk at the Breakthrough Discuss conference here at Stanford University.

And Earth’s so-called sister planet could potentially support life to this day, at least in places. Though Venus’ surface has gone hellish hothouse, the environment a few dozen miles high in the skies is pretty benign, Grinspoon and others have stressed. Temperatures and pressures up there are close to those of Earth’s surface, so it’s possible that Venusian life — if it ever existed — didn’t die out with the dramatic climate shift long ago but rather retreated into the clouds.

Those clouds are made mostly of sulfuric acid, which would seem to argue against the Venus-life idea. But over the last few decades, biologists have found all manner of hardy microbes here on Earth capable of tolerating similarly extreme conditions. And these same acidic Venus clouds could potentially provide chemical energy to any microbes that may be floating around up there, researchers have said.

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