Backyard Observatory

Potential Sign of Life Found in the Clouds of Venus

Researchers have found phosphine, a potential indicator of life on Earth's sister planet.

signs of alien life on Venus
An "artistic impression" of Venus. | ESO/M. Kornmesser & NASA/JPL/Caltech
An "artistic impression" of Venus. | ESO/M. Kornmesser & NASA/JPL/Caltech

Scientists have spent an enormous amount of time looking for life on Mars. So, when we think of some form of alien life existing within our solar system, we tend to think about Mars (maybe Titan or Europa). But a paper published today in Nature Astronomy has exciting revelations about the planet that comes closest to Earth: Venus

Scientists have previously suggested there's a possibility some form of life might be able to exist in the clouds over Venus. Now, there's evidence that this could be true. Astronomer Jane Greaves of Cardiff University, along with her team, announced they have detected a small amount of phosphine in the clouds of Venus through multiple telescopes on Earth.

“When we got the first hints of phosphine in Venus’s spectrum, it was a shock!" said Greaves in the European Southern Observatory (ESO) announcement. Here on Earth, phosphine is produced by bacteria in low-oxygen environments like swamps and wetlands. "Any organisms on Venus will probably be very different to their Earth cousins, but they too could be the source of phosphine in the atmosphere," the ESO announcement states.

life on venus
This artistic impression depicts Venus, where scientists have confirmed the detection of phosphine molecules, a representation of which is shown in the inset. | ESO/M. Kornmesser/L. Calçada & NASA/JPL/Caltech

The presence of the foul-smelling gas could indicate life on Earth's sister planet. Though, as highlighted by the New York Times, the research team has not confirmed the presence of bacteria or other forms of life. More observations and a science mission to the planet would be required to confirm the existence of life. However, the researchers could not come up with a geological or chemical explanation for the presence of phosphine in the quantities detected, per NPR's Nell Greenfieldboyce. "These non-biological sources were found to make at most one ten thousandth of the amount of phosphine that the telescopes saw," the ESO writes. 

The most likely conclusion the researchers were left with: a biological source. We're not talking about tiny green beings with ray guns. (If we've learned anything from cartoons it's that those tiny green beings are definitely Martians and they'd have no business on Venus.) That potential life would be living dozens of miles over the Venusian surface inside "incredibly acidic" clouds. It's a thrilling conclusion, especially considering that the surface of the planet is immensely hostile. It's so hot that life existing there is extraordinarily unlikely. 

"Finding phosphine on Venus was an unexpected bonus," said team member Clara Sousa Silva of MIT, who has been researching phosphine as a potential bioindicator on planets around other stars. "The discovery raises many questions, such as how any organisms could survive. On Earth, some microbes can cope with up to about 5% of acid in their environment -- but the clouds of Venus are almost entirely made of acid."

The discovery is no guarantee of life on the second planet from the sun, but it's an inspiring discovery that is likely to be the impetus for ongoing studies and science missions to Venus in the coming years. 

Ready to go stargazing?

Here are all the best stargazing events that you can get out and see this month or you could stay in a stream the northern lights from home. If you're just getting started, check out our guide to astronomy for beginners or easy stargazing road trips from big US cities

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Dustin Nelson is a Senior Staff Writer at Thrillist. Follow him @dlukenelson.