An international research group, including scientists from the Massachusetts Institute of Technology, Cardiff University, and other institutions have observed what may be signs of life in the clouds of Venus.

A paper about chemistry on Venus was published in Nature Astronomy several days ago, describing evidence of potential microbes that may inhabit the acidic Venusian cloud. Scientists detected traces of phosphine, a gas that on Earth is produced by anaerobic lifeforms that live in environments without oxygen. And it is the fact that no non-biological or non-geological chemical reaction or process produces this gas on our planet that makes this discovery intriguing and surprising.

“This was an experiment made out of pure curiosity, really. I thought we’d be able to rule out extreme scenarios, like the clouds being stuffed full of organisms. When we got the first hints of phosphine in Venus’ spectrum, it was a shock,” said Jane Greaves, a professor at Cardiff University who led the team of researchers.

The discovery was made with the James Clerk Maxwell Telescope help in Hawaii and the Atacama Large Millimeter/submillimeter Array in Chile. However, the news is not particularly 100% evidence that there’s life on Venus since it is very different from Earth, and the chemical reactions that produce phosphine may be caused not by life but by something else, which is yet to discover.

The conditions on Venus are extremely harsh, with clouds consisting of sulfuric acid and air being mostly carbon dioxide. And even though there is a region there where the atmospheric pressure and temperature are similar to those on Earth, it is still unknown how life could possibly survive on Venus.

If it eventually turns out that there is some kind of life on Venus, it would mean that we would need to radically rethink what habitable zone is and widen our search for life beyond the Solar System.

NASA was not involved in the research. However, it has an extensive astrobiology program that searches for life across the solar system and the universe in general, so the space agency says that since potential life beyond Earth has been discovered, two of the next four candidate missions for NASA’s Discovery Program will be focused on Venus. If the mission to Venus actually takes place, a robotic probe will be sent there to determine whether the planet harbors life.

This summer, three missions were launched to Mars in the hope of finding signs of past life on the Red Planet as well. In July, NASA sent its Perseverance rover to Mars to begin looking for signs of ancient microbial and micro-organic life on the planet that may have existed 3.8 billion years ago in its rocks and dirt. But Perseverance is not the only Mars visitor. Upon arrival, it will join Hope Probe, the United Arab Emirates’ weather satellite, and China’s Tianwen-1 mission. Three missions were planned for this summer because the Earth and Mars are now in alignment on the same side of the sun, which happens every 26 months.

HypeScienceSpaceNASAVenus