Scientists said Monday that a gas associated with microbial life has been detected in the caustic clouds of Earth’s neighboring planet, Venus.
Reuters reports scientists have discovered phosphine in Venus’s atmosphere, an indication that life may be present in the clouds of the hellish planet next door. On Earth, phosphine is produced by bacteria that thrive in oxygen-starved environments. Using the James Clerk Maxwell Telescope in Hawaii, the international team of scientists first spotted the gas present on Venus and later confirmed it using the Atacama Large Millimeter Array (ALMA) radio telescope in Chile.
“I was very surprised — stunned, in fact,” astronomer Jane Greaves of Cardiff University in Wales and lead author of the research published in the journal Nature Astronomy told reporters.
Clara Sousa-Silva, a Massachusetts Institute of Technology molecular astrophysicist who co-authored the study, indicated the presence of life is the most likely explanation for phosphine being in Venus’s atmosphere. “With what we currently know of Venus, the most plausible explanation for phosphine, as fantastical as it might sound, is life,” she said.
No life has been directly detected on the planet, but phosphine is one “biosignature,” or indirect evidence of life on faraway worlds, that scientists look for around our solar system and beyond, according to Science News.
“I should emphasize that life, as an explanation for our discovery, should be, as always, the last resort,” she added. “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, which is made up of one phosphorous atom and three hydrogen atoms, is toxic to humans. The researchers looked into all potential non-biological explanations for the phosphine, including volcanism, meteorites, lightning, and various chemical reactions, but none seemed to be the likely source.
Surface temperatures on Venus can reach 880 degrees Fahrenheit, but the Venusian atmosphere is far more mild, often maintaining pleasant, Earth-like temperatures. Scientists believe many eons ago, Venus had an Earth-like climate and was bathed in oceans and that life could have been kickstarted during that time.
If Venus is home to aerial microbes, researchers say they’d have plenty of resources to survive on; however, Venus’s atmosphere is too sulfuric to support any known Earth-bound bacteria. They also say something is continually producing the phosphine, as Venus is rich in elements that would normally break it down.
“Something must be creating the phosphine on Venus as fast as it is being destroyed,” said Anita Richards, an astrophysicist associated with the University of Manchester in England, who also co-authored the study.
“If it’s microorganisms, they would have access to some sunlight and water, and maybe live in liquid droplets to stop themselves dehydrating, but they would need some unknown mechanism to protect against corrosion by acid,” Greaves said.
On Earth, bacteria that produce phosphine live in environments starved of oxygen such as sewage plants, swamps, rice fields, and the intestinal tracts of animals.
While Mars has been the focus for many recent space missions and probes, scientists say another probe will need to be sent to Venus to confirm the presence of life. Such a mission could sample clouds and the surface of Venus to find the source of the phosphine, reports CNN. No such mission is currently planned.