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The discovery of phosphine in the clouds of Venus has prompted NASA administrator Jim Bridenstine to call for a new global research focus.
Earth’s planetary neighbour, Venus, has set the scientific world alight with the discovery of a rare molecule called phosphine in its clouds that could indicate the existence of aerial, microbial life. Now, tweeting his response to the news, NASA administrator Jim Bridenstine said this discovery is “the most significant development yet in building the case for life off Earth”.
“About 10 years ago, NASA discovered microbial life at 120,000ft [3,657 metres] in Earth’s upper atmosphere. It’s time to prioritise Venus”.
The discovery of phosphine was made by an international team of astronomers led by Prof Jane Greaves of Cardiff University using 45 telescopes of the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. This helped confirm that the gas was in small concentrations in Venus’s clouds at about 20 molecules per billion.
What makes the discovery potentially game-changing is that, as far as we know, phosphine is only made industrially or by microbes that thrive in oxygen-free environments. While non-biological explanations for the gas include volcanoes, lightning or minerals blown upwards, these could only account for one-10,000th of the amount of phosphine the telescopes saw.
The research team said that to create the observed quantity of phosphine on Venus, terrestrial organisms would only need to work at about 10pc of their maximum productivity.
Speaking of the team’s reaction, Greaves said: “I thought we’d just be able to rule out extreme scenarios, like the clouds being stuffed full of organisms. When we got the first hints of phosphine in Venus’ spectrum, it was a shock!”
Looking forward to ‘robust discussion’
If microbial life is to exist in the clouds of Venus, it will likely be very different to what we find on Earth as it must be able to survive hyper-acidic conditions. On Earth, some microbes can cope with up to 5pc acidity in their environment, but the clouds of Venus are almost entirely made of acid.
However, it is still too early to tell whether this is indeed the first discovery of life on another planet.
“The non-biological production of phosphine on Venus is excluded by our current understanding of phosphine chemistry in rocky planets’ atmospheres,” said European Southern Observatory astronomer, Leonardo Testi, who was not involved in this research.
“Confirming the existence of life on Venus’s atmosphere would be a major breakthrough for astrobiology; thus, it is essential to follow up on this exciting result with theoretical and observational studies to exclude the possibility that phosphine on rocky planets may also have a chemical origin different than on Earth.”
Despite Bridenstine’s proclamation to make Venus a top priority for research, NASA’s official statement erred more on the side of caution saying that it couldn’t comment directly except to say “we trust in the scientific peer review process and look forward to the robust discussion that will follow its publication”.
