. | . |
Phosphine on Venus a step toward understanding biomarker molecules by Staff Writers Tokyo, Japan (SPX) Sep 16, 2020
An international team of astronomers detected phosphine (PH3) in the atmosphere of Venus. They studied the origin of phosphine, but no inorganic processes, including supply from volcanos and atmospheric photochemistry can explain the detected amount of phosphine. The phosphine is believed to originate from unknown photochemistry or geochemistry, but the team does not completely reject the possibility of biological origin. This discovery is crucial to examine the validity of phosphine as a biomarker. "When we got the first hints of phosphine in Venus's spectrum, it was a shock!", says team leader Jane Greaves of Cardiff University in the UK, who first spotted signs of phosphine in observations from the James Clerk Maxwell Telescope (JCMT), operated by the East Asian Observatory, in Hawai'i. Confirming their discovery required the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, a more sensitive telescope. The reason why she was so shocked is that phosphine can be produced by microbes on the Earth , although the research team does not think that they found life on Venus. How do you find life on a planet from quite far away? One way is to study its atmosphere and find a biomarker that can be evidence of the presence of living forms. If a molecule in the atmosphere is mainly produced by living organisms and the contribution from abiotic origins is negligibly small, it can be a good biomarker. The international team led by Greaves, including Hideo Sagawa at Kyoto Sangyo University, studied the signal of phosphine in the radio spectra and found that the amount of the molecule is about 20 parts per billion in the atmospheric molecules. This is quite a small amount, but enough to astonish the researchers. This is because researchers have supposed that most of the phosphorus, if it existed in the first place, would bind with oxygen atoms because the Venusian atmosphere has a huge amount of oxygen atoms, although most of them are in the form of carbon dioxide (CO2). The team carefully examined the possible origins of the phosphine: production by chemical reaction in the atmosphere driven by strong sunlight or lightning, supply from volcanic activity, and delivery by meteorites. The team found that all of these known processes failed to produce the observed amount of phosphine. The amount of phosphine molecules produced by those processes is 10,000 times smaller than the amount detected with the radio telescopes. The researchers supposed that phosphine is produced by unknown photochemistry or geochemistry, but they also considered the possibility of biological origin. On Earth, some microbes produce and egest phosphine. If similar living organisms were in the Venusian atmosphere, they could produce the detected amount of phosphine. "Although we concluded that known chemical processes cannot produce enough phosphine, there remains the possibility that some hitherto unknown abiotic process exists on Venus," says Sagawa. "We have a lot of homework to do before reaching an exotic conclusion, including re-observation of Venus to verify the present result itself." Venus is Earth's twin, in terms of size. However, the atmospheres of the two planets are quite different. Venus has a very think atmosphere and the devastating greenhouse effect raises the surface temperature as high as 460 degrees Celsius. Some researchers argue that the upper atmosphere is much milder and possibly habitable, but the extremely dry and deadly acidic atmosphere would make it difficult for a life form similar to the ones on Earth to survive on Venus. Further observations with large telescopes on the Earth, including ALMA, and ultimately on-site observations and a sample return of the Venusian atmosphere by space probes will provide crucial information to understand the mysterious origin of the phosphine. "Phosphine Gas in the Cloud Decks of Venus"
Astronomers may have found a signature of life on Venus Boston MA (SPX) Sep 15, 2020 The search for life beyond Earth has largely revolved around our rocky red neighbor. NASA has launched multiple rovers over the years, with a new one currently en route, to sift through Mars' dusty surface for signs of water and other hints of habitability. Now, in a surprising twist, scientists at MIT, Cardiff University, and elsewhere have observed what may be signs of life in the clouds of our other, even closer planetary neighbor, Venus. While they have not found direct evidence of living orga ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |