The discovery of large-scale phosphine gas launched on Venus – a possible ‘biosignature’ suggesting that the hellish planet may have living microbes in its clouds – was probably caused by a very different gas that is not a clear sign of life is not.
Studies by a team of American scientists suggest that radio telescope observations that presumably reveal phosphine on Venus are rather caused by sulfur dioxide, which gives signals that may be confused with phosphine under certain conditions.
The latest research published in January also suggests that the radio signals originated far above the Venusian clouds, where phosphine would be rapidly destroyed by other chemicals, further giving weight to the idea that it was caused by sulfur dioxide.
“Our new research makes the detection of phosphine much less likely,” said Victoria Meadows, an astrobiologist and professor of astronomy at the University of Washington in Seattle, who led the studies. “We can explain the observations simply using sulfur dioxide … and it does not require any unknown chemistry.”
Sulfur dioxide is a relatively common gas on Venus, where it is thought to be caused by the chemistry of the thick, unbreakable atmosphere and possibly by volcanoes. It is also found in the earth’s atmosphere, where it comes mainly from volcanoes and from the burning of fossil fuels.
Phosphine gas, on the other hand, is created by some microorganisms on Earth as they digest organic matter, and is therefore considered a possible ‘biosignature’ – meaning that its detection in the atmosphere of distant planets may be a sign of elemental life .
The British scientific team, which first reported the possible detection of phosphine on Venus, said it knew of no chemical process that could produce it – leading to the suggestion that it could come from microbes floating in the planet’s clouds. kilometers above the superhot surface. .
After the scientists reconsidered their initial findings with recalibrated data from the ALMA telescope in the Atacama Desert in Chile, they said they still think they have detected phosphine on Venus, but even less of it. They now hope to provide a detailed answer to the new research within a few weeks.
Ignas Snellen, a professor of acting astrophysics at the University of Leiden in the Netherlands, who was not involved in the latest studies, said it now seems unlikely that there is any phosphine on Venus.
The recalibrated data from the ALMA telescopes showed no evidence of phosphine, and earlier finds by the James Clerk Maxwell Radio Telescope in Hawaii can now be declared sulfur dioxide.
“I think the story of phosphine and the possible life on Venus stops here,” he said.