You can forget about moving to Venus as it is impossible for life to exist there, according to a new study that measured water concentration in Venus’s atmosphere. A paper published in 2020, however, had kindled hopes when it claimed to have detected phosphine gas — known to be produced by bacteria on Earth — in the planet’s clouds.
The authors have since called their own findings into question.
But the claim had inspired scientists at Queen’s University Belfast to test the theory from a different angle: whether there is enough water in Venus’s atmosphere to make life possible.
In 2017, microbiologist John Hallsworth discovered a terrestrial fungus that can survive at 58.5 percent relative humidity — the driest conditions at which biological activity has ever been measured.
“We bent over backwards to argue that the most extreme, tolerant microbes on Earth could potentially have activity on Venus,” said Hallsworth at a press conference.
But he said nothing could cope with the miniscule amount of water in the planet’s atmosphere, which is equivalent to a relative humidity of 0.4 percent.
“It’s more than 100 times too low. It’s almost at the bottom of the scale, at an unbridgeable distance from what life requires to be active.”
To calculate the concentration of water, scientists used existing measurements from seven US and Soviet probes and one orbiter mission sent to Venus in the late 1970s and early 1980s.
Chris McKay, a Nasa planetary scientist and co-author of the research published in Nature Astronomy, noted that the conclusions of the study were based on the limited direct observations available, and therefore incomplete.
“It’s hard to imagine that the results will change as we do further exploration,” McKay told reporters.
The team also analysed measurements taken from probes that visited other planets — and discovered potentially the right amount of water activity to support life in the clouds of Jupiter. “The results were much more optimistic,” said McKay.
Three more Venus missions are planned for sometime around 2030 and McKay feels certain they will confirm the measurements used for the study.
He also said that one mission could shed light on a question not addressed by current research: whether life could have existed on Venus several billion years ago.
“There could’ve been a time when Venus was earth-like,” McKay said.
From : pk.mashable.com