Rethinking Biosignatures: Uncertainty, Abiotic Alternatives, and Multi-Gas Signals in Exoplanet Atmospheres

To the point

Scientists now believe that detecting life beyond Earth will rely on combinations of atmospheric gases and probabilistic reasoning rather than a single biosignature gas, because of large abiotic uncertainties and ongoing debates among researchers such as Peter Vickers, Daniel Angerhausen, Cole Mathis, Harrison Smith, Sarah Rugheimer and Clara Sousa-Silva, while JWST measures atmospheric composition and future missions will test both suspected biosignatures and abiotic alternatives.