Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Astronomers find a possible sign of life on Venus

Astronomers find a possible sign of life on Venus



Traces of a rare molecule known as phosphine have been found in Venus’ hell, strongly acidic atmosphere, astronomers announced on Monday – they provided a tempting clue about the possibility of life. Phosphine molecules found on Earth are primarily the result of human industry or the actions of microbes that thrive in oxygen-free environments.

Scientists do not claim that life has been found on the other planet from the sun. But observations at least suggest the possibility of microbial activity in the upper layers of Venus’ atmosphere, far away from the planet’s inhospitable surface.

“We have discovered a rare gas called phosphine in the atmosphere of our neighboring planet Venus,”

; said Jane Greaves, a professor at Cardiff University in the UK and lead author of a report published in Nature Astronomy. “And the reason for our excitement is that phosphorus on Earth is produced by microorganisms that live in oxygen-free environments. And then there is a chance that we have discovered some living organism in the clouds of Venus.”

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A false-colored image of Venus as taken by Ultraviolet Imager aboard Japan’s Venus Climate Orbiter (Akatsuiki).

JAXA


Still, the team said much more research is needed to support such a claim, extraordinary as it would be.

“To make this quite extraordinary claim that there may be life there, we really have to exclude everything, and that is why we are very careful to say that we do not claim that there is life, but claiming that there is something that is really unknown and it could be life, “said team member William Bains, a researcher at MIT.

Sara Seager, an MIT scientist studying exoplanet atmospheres, agreed, saying “we do not claim to have found life on Venus.”

“We claim the safe detection of phosphine gas, the existence of which is a mystery,” she said. “Phosphine can be produced by some (non-biological) processes on Venus, but only in such incredibly small amounts it is not enough to explain our observation. So we have this other exciting, enticing possibility: that there may be some kind of life in the clouds of Venus. “

Mars has long been considered the best candidate in the solar system beyond Earth to have hosted microbial life in the distant past or even in the present, as suggested by background levels of methane. NASA, the European Space Agency, China, India, Russia and the United Arab Emirates are all pursuing exploration of the red planet in one form or another.

NASA is also planning a flagship mission to study moons of Jupiter. Scientists believe that one of the planet’s largest and most famous moons, Europe, heated by tidal loads and gravitational interactions with other moons, a salty, possibly habitable sea ends up under its icy crust. Other frozen moons in the outer solar system, possible “water worlds”, are also candidates for study.

But Venus is the victim of a runaway greenhouse effect, where thick clouds in a predominantly carbon dioxide atmosphere capture sunlight and produce surface temperatures hovering to nearly 900 degrees, hot enough to melt lead.

In the upper atmosphere of the planet, however, the temperature is much more hospitable. Despite the acidic nature of the clouds, researchers have speculated that it may be possible for foreign microbes to exist.

“The surface conditions there today are really hostile, the temperature is enough to melt our landers,” Greaves said. “But it is assumed that the surface much earlier in Venus’ history was much cooler and wetter, and life could possibly have originated.

“There is a long-standing theory that some of the smallest life forms may have been able to develop upwards in the high clouds. The conditions there are certainly not nice, they are extremely acidic and it is very windy, but on the other side, if you talk about 50 to 60 kilometers up, then the pressure is pretty much like it is on the earth’s surface, and the temperature is quite fine, maybe up to about 85 degrees Fahrenheit.So it has been assumed that this is a living habitat Today. “

Greaves ‘team studied the spectra of Venus’ atmosphere using the James Clerk Maxwell Telescope in Hawaii and 45 radio telescopic antennas in the Atacama Large Millimeter / submillimeter Array in Chile and were surprised to see unmistakable signs of phosphine. “It was a shock,” Greaves said.

The detection was rewarded with additional observation time on the ALMA array and “eventually we found that both observatories had seen the same, weak absorption at the right wavelength to be phosphine gas, where the molecules are backlit by the warmer clouds below,” Greaves said in a declaration.

Only trace amounts were observed, approx. 20 molecules per Billion. But further research showed that natural sources of phosphine – volcanoes, lightning, minerals blown into the atmosphere, the effects of sunlight – would only generate a tenth of a thousandth of the amount actually discovered.

The team can rule out many non-biological ways to generate the observed levels of phosphine, but that does not mean that life is the only explanation. The atmosphere in Venus is 90% sulfuric acid, which raises “many questions, such as how any organism could survive,” said MIT researcher Cara Sousa Silva.

“On the ground, some microbes can handle up to approx. 5% acid in their environment, but the Venus clouds are almost exclusively made of acid, ”she said.

Greaves’ team is awaiting additional telescope time to look for signs of other gases associated with biological activity and to determine the temperature of the clouds where the phosphine is present for further insight. Ultimately, future visits with spacecraft will likely be necessary to fully address the issue.

“There can always be something we overlooked,” Seager said. “Ultimately, the only thing that will answer this question for us – is there life, is there no life – actually goes to Venus and makes more detailed measurements for signs of life and perhaps life itself.”




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