18.09.2020
12:08
A group of experts found for the first time outside the Earth a molecule called Phosphine, possibly created by microbes or bacteria
September 14, 2020 Share on FacebookShare Share on TwitterTweet Share on WhatsAppShareIs there life on Venus? The Royal Astronomical Society’s explanation of the finding
A group of astronomers discovered in the acidic clouds of Venus a gas called phosphine that indicates that microbes may inhabit Earth’s inhospitable neighbor, a clear indication of the presence of life beyond our planet, according to a study published Monday. in Nature Astronomy.
The “apparent presence” of phosphine was detected in the cloud layers of Venus and could be due to an unknown phenomenon or a form of life, according to the scientists. The researchers noted that on Earth, phosphine is produced by bacteria that thrive in oxygen-free environments.
This artist’s impression represents the planet Venus, where scientists have confirmed the detection of phosphine molecules. (ESO / M. Kornmesser and NASA / JPL / Caltech via REUTERS)
The international scientific team first detected phosphine using the James Clerk Maxwell telescope in Hawaii and confirmed it using the Atacama Large Millimeter / submillimeter Array (ALMA) radio telescope in Chile.
“I was very surprised, actually stunned,” said astronomer Jane Greaves of Cardiff University in Wales, lead author of the research published in the journal Nature Astronomy .
The existence of extraterrestrial life has long been one of the fundamental questions of science. Scientists have used probes and telescopes to search for “biosignatures,” indirect signs of life, on other planets and moons in our solar system and beyond.
Stock photo illustrative of the planet Venus seen from Egypt. May 15, 2015. REUTERS / Amr Abdallah Dalsh
“With what we know of Venus, the most plausible explanation of the phosphine fantastic enough, it is life , “ said molecular astrophysics at the Institute of Technology of Massachusetts and coauthor of the study, Clara Sousa-Silva.
“I must emphasize that life, as an explanation for our discovery, must be, as always, the last possibility, ” added Sousa-Silva. “This is important because, if it is phosphine, and 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 throughout our galaxy. ”
Phosphine , a phosphorous atom with three attached hydrogen atoms, is highly toxic to people.
This artist’s impression represents the planet Venus, where scientists have confirmed the detection of phosphine molecules, the representation of which is shown in the inset. (ESO / M. Kornmesser / L. Calcada & NASA / JPL / Caltech via REUTERS)
Ground-based telescopes like the ones used in this research help scientists study the chemistry and other characteristics of celestial objects.
Phosphine was observed at 20 parts per billion in the atmosphere of Venus, a minimal concentration. Greaves said the researchers examined possible non-biological sources such as volcanism, meteorites, lightning and various types of chemical reactions, but none seemed viable.
Research continues to confirm the presence of life or find an alternative explanation.
FILE PHOTO: Image courtesy of NASA showing the planet Venus as it transits the Sun, June 5, 2012. (REUTERS / NASA / AIA / Solar Dynamics Observatory)
Venus is the closest planetary neighbor to Earth . Similar in structure but slightly smaller than Earth, it is the second planet from the sun. Earth is the third. Venus is shrouded in a thick, toxic atmosphere that traps heat. Surface temperatures reach 880 degrees Fahrenheit (471 degrees Celsius), hot enough to melt lead.
“I can only speculate what life could survive on Venus, if it is there . No life could survive on the surface of Venus, because it is completely inhospitable, even for completely different biochemistry than ours, ”Sousa-Silva said. “But long ago, Venus could have had life on its surface, before a runaway greenhouse effect left most of the planet completely uninhabitable.”
The acid test
Some scientists have suspected that high clouds on Venus, with mild temperatures around 30 degrees Celsius, could harbor airborne microbes that could withstand extreme acidity. These clouds contain approximately 90% sulfuric acid . Terrestrial microbes could not survive that acidity.
This artistic illustration shows the surface and atmosphere of Venus, as well as phosphine molecules. These molecules float in the windswept clouds of Venus at altitudes of 55 to 80 km, absorbing some of the millimeter waves that occur at lower altitudes. They were detected in the high clouds of Venus in data from the James Clerk Maxwell Telescope and the Large Millimeter / Submillimeter Telescope in the Atacama Desert, in which ESO is a partner. (ESO / M. Kornmesser / L. Calcada via REUTERS)
“If it’s microorganisms, they would have access to some sunlight and water, and maybe they would live in droplets of liquid to avoid dehydration, but they would need some unknown mechanism to protect against acid corrosion, ” Greaves said.
On Earth, microorganisms in “anaerobic” environments – ecosystems that do not depend on oxygen – produce phosphine. These include sewer plants, swamps, rice paddies, mudflats, lake sediments, and the droppings and intestinal tracts of many animals. Phosphine also arises non-biologically in certain industrial settings.
To produce phosphine, terrestrial bacteria take phosphate from minerals or biological material and add hydrogen.
“We have done everything possible to explain this discovery without the need for a biological process. With our current knowledge of phosphine, Venus, and geochemistry, we cannot explain the presence of phosphine in clouds on Venus. That doesn’t mean it’s life. It just means that some exotic process is producing phosphine, and our understanding of Venus needs to improve, ” said Clara Sousa-Silva.
Venus should be hostile to phosphine. Its surface and atmosphere are rich in oxygen compounds that would react quickly with phosphine and destroy it.
Data from NASA’s Magellan spacecraft and Pioneer Venus Orbiter is used in an undated composite image of the planet Venus. (NASA / JPL-Caltech / REUTERS)
“Something must be creating phosphine on Venus as fast as it is destroying itself,” said study co-author Anita Richards, an astrophysicist associated with the University of Manchester in England.
While previous robotic spacecraft have visited Venus, a new probe may be needed to confirm life.
“Fortunately, Venus is right next door, ” Sousa-Silva said. “So we can literally go and check.”
(With information from agencies)
