Venus is one of the harshest places in our solar system. Its heat can melt metal, and its thick atmosphere is toxic and crushing. Despite this, scientists have found two gases in the planet’s clouds that might hint at life.
During a meeting at the University of Hull in England on Wednesday, astronomers shared new evidence. They focused on a smelly gas called phosphine, which some believe exists on Venus. The discovery has sparked much debate among scientists, as reported by The Guardian.
Detection of ammonia in Venus’ clouds
Another team announced the possible discovery of ammonia on Venus. On Earth, this gas is mostly produced by living things and industries. Scientists say the presence of ammonia on Venus cannot easily be explained by the planet’s atmosphere or rocks.
These gases, known as biosignature gases, do not prove there is life on Venus. However, their detection will increase interest in the planet. It raises the possibility that life might have started when Venus had milder conditions and could still exist in parts of its atmosphere today.
Dr. Dave Clements, an astrophysics expert at Imperial College London, explained at the meeting: “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.”
The Venus session gets even more exciting! @jgreaves6 from Cardiff University reveals that as well as phosphine, a second potential biomarker gas – ammonia – has been tentatively detected in the clouds of Venus.
Again, it's important to stress these are preliminary findings. pic.twitter.com/pxptIkTzxF
— Royal Astronomical Society (@RoyalAstroSoc) July 17, 2024
The surface of Venus is extremely harsh, reaching about 450°C. The atmospheric pressure is 90 times greater than that of Earth, and there are clouds of sulfuric acid. However, about 50 kilometers (31 miles) above the surface, the temperature and pressure are more like Earth’s and might be tolerable for very tough microbes.
On Earth, phosphine gas is produced by microbes in places with little oxygen like the stomachs of badgers and penguin droppings. Other sources, like volcanic activity, produce very little phosphine, so on rocky planets, this gas is often seen as a sign of life, as reported by The Guardian.
Claim of phosphine on Venus
In 2020, a major claim about finding phosphine on Venus sparked controversy when later observations couldn’t confirm it. Dr. Clements and his team used the James Clerk Maxwell Telescope (JCMT) in Hawaii to settle the debate.
They tracked phosphine over time and found stronger evidence for its presence. They also noticed that the gas’s detection seemed to follow Venus’s day-night cycle.
“Our findings suggest that when the atmosphere is bathed in sunlight the phosphine is destroyed,” Clements said. “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.”
