Volcanoes may explain phosphine on Venus

Venus often Known as the Earth’s sister planet, neighboring twins of similar density and size. But the similarities end there. As the hottest planet in our solar system, the suffocating atmosphere of Venus is full of endothermic carbon dioxide and dense sulfuric acid clouds, shrouded in dry volcanic terrain.

Therefore, it is one of the last places anyone could think of to find life outside of our planet.

This is why in September last year, a group of scientists led by Jane Greaves of Cardiff University announced that they had discovered a Possible signs of alien life In the atmosphere of Venus.inside Learn, Published in Natural astronomy, They reported detecting a colorless and toxic gas called phosphine in the planet’s clouds and concluded that there is no known chemical or geological process to explain its existence.They believe that phosphine can represent life and point out Recent work Clara Sousa-Silva, an astrophysicist at the Massachusetts Institute of Technology, thinks this gas may be a biological feature. On the earth, phosphine usually exists in places with anaerobic organisms, including lakes, swamps, rice fields, and landfill sludge.

But when the news reached Cornell University astronomer Jonathan Lunine, he and graduate student Ngoc Truong immediately expressed suspicion. “The use of phosphine as a biomarker on Venus is problematic because the environment on Venus is completely different from that on Earth,” Truong said. He said that even on our own planet, there is some confusion as to whether phosphine is related to life, and he believes this should be confirmed before extrapolating these observations to an environment different from our planet.

Truong and Luine are not the only ones who have doubts: after the announcement of phosphine, the discovery was heatedly discussed on the Internet.Scientists weighed on Twitter posts, argued on Facebook posts, and swarmed arXiv.org, A preprint server for scientific research, to provide other theories for non-biological processes that may produce phosphine.

Truong, who had been studying the oceans on Saturn’s moons, convinced Lunin that they needed to further explore a potential source of phosphine, especially volcanoes.Their research has reached a climax New research Published in the journal on Monday Proceedings of the National Academy of SciencesIn it, Truong and Luine describe how phosphine enters the atmosphere of Venus. Trace amounts of phosphides (negatively charged phosphorus ions attached to metals such as iron) found deep in the mantle of Venus can be pulled to the surface by volcanic activity. When a volcano erupts, these phosphides may be sprayed into the atmosphere and chemically react with the sulfuric acid in the cloud to form phosphine.

“Our research only proposes a road map for assessing the eruption level of Venus,” Truong said. This requires two conditions to be a viable explanation. First of all, this planet must have volcanic activity. (Although thousands of volcanoes have been found in radar images of Venus, scientists lack data confirming recent volcanic eruptions, because so far, The lander can only withstand the heat and crushing pressure on the surface of Venus for about an hour.) “And it’s not just active in the sense of’Hawaiian volcanic activity’,” Lunie said, which usually produces lava flows that don’t have much explosiveness. Explosive volcanic activity is key, because a mechanism is needed to eject phosphide into the atmosphere.

Secondly, scientists need to verify whether phosphine really exists-that is Is currently a huge point of contentionLunine said that without this evidence, the volcano theory “becomes an empty hypothesis, not an hypothesis.”