Phosphine gas (a component of life) has been detected in the atmosphere of a brown dwarf (a failed star) called Wolf 1130C, which is approximately 54 light-years distant. The finding completely contradicts one of the most controversial concepts of astronomy: phosphine is a possible life indicator. The discovery, rather, indicates that this gas could be formed in extreme settings naturally, altering our perception of the potential indicators of life in the universe.
Phosphine found on Wolf 1130C
According to a paper, in October 2018, an international team observed Wolf 1130C with JWST and detected phosphine in its atmosphere with a concentration of approximately 0.1 parts per million. The presence of phosphine in cool, hydrogen-rich objects had been predicted by atmosphere models and thus was expected to be detected.
Notably, the team emphasises the fact that Wolf 1130C is too cold and uninhabitable to support life of any kind, so the phosphine must have been produced non-biologically. Co-author Adam Burgasser underlines that scientists should not be allowed to assume a biological origin before eliminating all natural processes. These findings are indicative of the high age of the brown dwarf and extremely low metallicity (abundance of heavy elements), which could enable the presence of phosphine.
The search for life
In the case of Venus, the discovery comes as a sobering experience. In 2020, Jane Greaves reported finding phosphine in the clouds of Venus, which she argued had a microbial origin, but this was controversial and not detected again by other astronomers. Recent discovery of brown-dwarfs suggests that phosphine may occur via normal chemical reactions, and thus there is speculation that any phosphine present on Venus may be of abiotic origin, as opposed to a biotic one.
