Scientists Spot Possible Signs of Life in Clouds of Venus
Researchers have presented new evidence for the presence of two gases that are closely related to life on Earth in the atmosphere of Venus.
As The Guardian reports, scientists at a national astronomy meeting in the UK have announced the tentative detection of ammonia, a gas that is primarily the result of biological activity on Earth, in the clouds above the planet's hellish surface.
A different team said it had found new evidence for the presence of phosphine back in 2020, in another possible indication of life — a conclusion that has been fiercely debated since it was first announced.
While the latest findings are far from definitive proof of life on Venus, a planet known for its scorching hot temperatures and extremely dense atmosphere, they're intriguing new data points in our efforts to explore our celestial neighborhood for signs of current — or ancient — life.
One possibility intriguing scientists is that life may have once flourished in the planet's ancient past.
"It could be that if Venus went through a warm, wet phase in the past then as runaway global warming took effect [life] would have evolved to survive in the only niche left to it — the clouds," Imperial College London astrophysics reader Dave Clements told audiences at this week's meeting, as quoted by The Guardian.
While Venus's surface is now hot enough to melt lead, the clouds swirling 30 miles above its surface experience far more balmy temperatures and pressure levels, not unlike conditions found back on Earth.
While phosphine gas can technically be produced by volcanic activity, it's far more abundantly produced by bacteria in oxygen-starved environments. Scientists therefore refer to it as a "biosignature" gas.
But whether the colorless and smelly gas really exists in Venus's clouds remains a subject of much debate. In September 2020, a team of researchers led by Jane Greaves from Cardiff University in the UK announced they had discovered significant sources of the stuff, news that turned the scientific world on its head.
However, the findings were immediately called into question by other scientists. Weeks later, researchers submitted a critique throwing cold water on Greaves and her colleagues' findings, arguing that they had found "no statistical evidence for phosphine in the atmosphere of Venus."
However, Greaves and her team have since attempted to back up their discovery by tracking signatures of the gas over time using the James Clerk Maxwell telescope in Hawaii.
"Our findings suggest that when the atmosphere is bathed in sunlight the phosphine is destroyed," she told scientists at this week's meeting. "All that we can say is that phosphine is there. We don’t know what’s producing it. It may be chemistry that we don’t understand. Or possibly life."
And the astronomer didn't stop there — in a separate talk, she offered up new observations suggesting the presence of ammonia as well.
But far more research needs to be done before we can conclude that the clouds of Venus can, or once could, host life.
"Even if we confirmed both of these [findings], it is not evidence that we have found these magic microbes and they’re living there today," Greaves admitted.
Fortunately, scientists are hoping to get a first-hand glimpse that could finally provide some answers. Earlier this year, the European Space Agency announced it had approved a mission dubbed Envision, which is designed to study the planet's inner and outer atmosphere.
More on Venus and life: Scientists Turn Radio Signal From Venus Into Audio You Can Listen to