The researchers did not find the actual life form, but pointed out that the phosphine on the earth is produced by bacteria that multiply in an oxygen-deficient environment. The international scientific team first discovered the phosphine using the James Clerk Maxwell telescope in Hawaii, and then confirmed it using the Atacama Large Millimeter/Submillimeter Array (ALMA) radio telescope in Chile.
Jane Greaves, an astronomer at Cardiff University in Wales, said: “I was very surprised-actually shocked.” The lead author of the study was published in the journal Natural Astronomy.
Long-lived alien life has always been one of the top issues of science. Scientists have used probes and telescopes to search for “biological features” (indirect signs of life) on other planets and moons inside and outside our solar system.
Clara Sousa-Silva, a molecular astrophysicist and research co-author at the Massachusetts Institute of Technology, said: “As far as our current understanding of Venus is concerned, the most reasonable explanation for phosphine , It sounds amazing.”
“I should emphasize that, as an explanation of what we found, life should be the last resort as usual,” Sousa-Silva added. “This is important because if it is phosphine, if it is life, it means that we are not alone. It also means that life itself must be very common, and there must be many other inhabited planets in the entire galaxy.”
Phosphine-a phosphorus atom with three hydrogen atoms-is highly toxic to humans.
As used in this study, ground-based telescopes can help scientists study the chemical properties and other characteristics of celestial bodies.
In the atmosphere of Venus, the content of phosphine is 10 parts per billion. Graves said that the researchers examined potential non-biological sources such as volcanism, meteorites, lightning and various types of chemical reactions, but none of them seemed feasible. Research continues to confirm the existence of life or search for alternative explanations.
Venus is the closest planetary neighbor on Earth. Its structure is similar, but slightly smaller than the earth, and it is the second planet after the sun. The earth is third. Venus is wrapped in a thick, poisonous atmosphere and emits heat. The surface temperature is as high as 880 degrees Fahrenheit (471 degrees Celsius), enough to melt lead.
“I can only speculate that if Venus does exist, then Venus may survive. Sousa-Silva said: “Even for a completely different biochemistry from ours, it is completely unsuitable for survival on the surface of Venus. “But a long time ago, before the runaway greenhouse effect made most people on Earth completely uninhabitable, Venus could have life on its surface. ”
Some scientists suspect that the mild temperature of the Venus high cloud is about 86 degrees Fahrenheit (30 degrees Celsius), and it may harbor microorganisms in the air that can withstand extreme acidity. These clouds contain about 90% sulfuric acid. Earth microorganisms are not immune to that acidity.
Graves said: “If it is microorganisms, they will get some sunlight and water, and may live in droplets to prevent their own dehydration, but they will need some unknown mechanism to prevent acid corrosion.”
On earth, microbes in an “anaerobic” environment-ecosystems that do not rely on oxygen produce phosphine. These include sewage treatment plants, swamps, rice fields, marshes, lake sediments, and many animal wastes and intestines. In some industrial environments, phosphines are also produced abiotically.
To produce phosphine, terrestrial bacteria absorb phosphorus from minerals or biological materials and add hydrogen.
“We did our best to explain this discovery without going through a biological process. Based on our current understanding of phosphine, Venus, and geochemistry, we cannot explain the presence of phosphine in the Venusian cloud. That doesn’t mean It is life. It just means that phosphine is being produced by some unusual process, and our understanding of Venus needs to work.”
Venus should be bad for phosphine. Its surface and atmosphere are rich in oxygen compounds that quickly react with phosphine and destroy its phosphorus.
Anita Richards, an astrophysicist related to the University of Manchester in England, the co-author of the study, said: “Something must produce phosphine on Venus as soon as possible.”
When the previous robotic spacecraft visited Venus, a new probe may be needed to confirm life.
“Fortunately, Venus is next door,” Sousa-Silva said. “So we can literally check.”