 Space News space history and artifacts articles Messages space history discussion forums Sightings worldwide astronaut appearances Resources selected space history documents |
If you have previously registered, but forgotten your password, click here.
To create the observed quantity of phosphine on Venus, terrestrial organisms would only need to work at about 10% of their maximum productivity, according to calculations by Dr Paul Rimmer of Cambridge University. Any microbes on Venus will likely be very different to their Earth cousins though, to survive in hyper-acidic conditions. Earth bacteria can absorb phosphate minerals, add hydrogen, and ultimately expel phosphine gas. It costs them energy to do this, so why they do it is not clear. The phosphine could be just a waste product, but other scientists have suggested purposes like warding off rival bacteria. Another MIT team-member, Dr Clara Sousa Silva, was also thinking about searching for phosphine as a 'biosignature' gas of non-oxygen-using life on planets around other stars, because normal chemistry makes so little of it. She comments: "Finding phosphine on Venus was an unexpected bonus! The discovery raises many questions, such as how any organisms could survive. On Earth, some microbes can cope with up to about 5% of acid in their environment – but the clouds of Venus are almost entirely made of acid." Other possible biosignatures in the Solar System may exist, like methane on Mars and water venting from the icy moons Europa and Enceladus. On Venus, it has been suggested that dark streaks where ultraviolet light is absorbed could come from colonies of microbes. The Akatsuki spacecraft, launched by the Japanese space agency JAXA, is currently mapping these dark streaks to understand more about this "unknown ultraviolet absorber". The team believes their discovery is significant because they can rule out many alternative ways to make phosphine, but they acknowledge that confirming the presence of "life" needs a lot more work. Although the high clouds of Venus have temperatures up to a pleasant 30 degrees centigrade, they are incredibly acidic – around 90% sulphuric acid – posing major issues for microbes to survive there. Professor Sara Seager and Dr Janusz Petkowski, also both at MIT, are investigating how microbes could shield themselves inside droplets. The team are now eagerly awaiting more telescope time, for example to establish whether the phosphine is in a relatively temperate part of the clouds, and to look for other gases associated with life. New space missions could also travel to our neighbouring planet, and sample the clouds in situ to further search for signs of life. Professor Emma Bunce, President of the Royal Astronomical Society, congratulated the team on their work: "A key question in science is whether life exists beyond Earth, and the discovery by Professor Jane Greaves and her team is a key step forward in that quest. I'm particularly delighted to see UK scientists leading such an important breakthrough – something that makes a strong case for a return space mission to Venus." Science Minister Amanda Solloway said: "Venus has for decades captured the imagination of scientists and astronomers across the world." "This discovery is immensely exciting, helping us increase our understanding of the universe and even whether there could be life on Venus. I am incredibly proud that this fascinating detection was led by some of the UK's leading scientists and engineers using state of the art facilities built on our own soil." | ||||||||
| Robert Pearlman | NASA release Announcement About Research on Venus's ChemistryFrom NASA Administrator Jim Bridenstine (via Twitter): Life on Venus? The discovery of phosphine, a byproduct of anaerobic biology, is the most significant development yet in building the case for life off Earth. About 10 years ago NASA discovered microbial life at 120,000 feet in Earth's upper atmosphere. It's time to prioritize Venus. | |||||||
| Robert Pearlman | Atacama Large Millimeter/submillimeter Array (ALMA) statement Following the high-profile announcement in mid-September of the discovery of phosphine, a possible bio-marker, on the atmosphere of Venus, the study by Jane Greaves and her team and its associated data have been the subject of intense scrutiny by the scientific community, as part of the usual way science works. As a result of this process, ALMA staff identified a possible issue in the ALMA data, which was used to confirm the detection of phosphine. | |||||||
| SpaceAholic | Pioneer 13 may have detected the gas as well. ...digging through archival NASA data, Rakesh Mogul, a biochemist at Cal Poly Pomona in California, and colleagues have found a hint of phosphine picked up by Pioneer 13 — a probe that reached Venus in December 1978. | |||||||
advertisement