1. Phosphine gas in the cloud decks of Venus
- Author
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Sara Seager, Jim Hoge, Janusz J. Petkowski, David L. Clements, Jane Greaves, E’lisa Lee, Paul B. Rimmer, Anita M. S. Richards, Per Friberg, Sukrit Ranjan, William Bains, Hideo Sagawa, Clara Sousa-Silva, Emily Drabek-Maunder, Zhuchang Zhan, Iain Coulson, Ingo Mueller-Wodarg, Helen J. Fraser, Annabel Cartwright, Greaves, JS [0000-0002-3133-413X], Richards, AMS [0000-0002-3880-2450], Rimmer, PB [0000-0002-7180-081X], Sagawa, H [0000-0003-2064-2863], Seager, S [0000-0002-6892-6948], Petkowski, JJ [0000-0002-1921-4848], Sousa-Silva, C [0000-0002-7853-6871], Mueller-Wodarg, I [0000-0001-6308-7826], Friberg, P [0000-0002-8010-8454], Apollo - University of Cambridge Repository, Science and Technology Facilities Council (STFC), Imperial College Trust, and Science and Technology Facilities Council
- Subjects
010504 meteorology & atmospheric sciences ,sub-01 ,FOS: Physical sciences ,SULFUR ,Venus ,Cloud computing ,5109 Space Sciences ,Astronomy & Astrophysics ,01 natural sciences ,Astrobiology ,Atmosphere ,chemistry.chemical_compound ,CHEMISTRY ,0103 physical sciences ,LOWER ATMOSPHERE ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Earth and Planetary Astrophysics (astro-ph.EP) ,SPECTRUM ,geography ,Science & Technology ,geography.geographical_feature_category ,biology ,sub-99 ,business.industry ,Nearest neighbour ,Astronomy and Astrophysics ,biology.organism_classification ,Lightning ,Trace gas ,LIFE ,Volcano ,chemistry ,WATER-VAPOR ,5101 Astronomical Sciences ,13. Climate action ,Physical Sciences ,PH3 ,ENCELADUS ,CHEMICAL KINETIC-MODEL ,business ,51 Physical Sciences ,5107 Particle and High Energy Physics ,Phosphine ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Measurements of trace gases in planetary atmospheres help us explore chemical conditions different to those on Earth. Our nearest neighbour, Venus, has cloud decks that are temperate but hyperacidic. Here we report the apparent presence of phosphine (PH3) gas in Venus’s atmosphere, where any phosphorus should be in oxidized forms. Single-line millimetre-waveband spectral detections (quality up to ~15σ) from the JCMT and ALMA telescopes have no other plausible identification. Atmospheric PH3 at ~20 ppb abundance is inferred. The presence of PH3 is unexplained after exhaustive study of steady-state chemistry and photochemical pathways, with no currently known abiotic production routes in Venus’s atmosphere, clouds, surface and subsurface, or from lightning, volcanic or meteoritic delivery. PH3 could originate from unknown photochemistry or geochemistry, or, by analogy with biological production of PH3 on Earth, from the presence of life. Other PH3 spectral features should be sought, while in situ cloud and surface sampling could examine sources of this gas. The detection of ~20 ppb of phosphine in Venus clouds by observations in the millimetre-wavelength range from JCMT and ALMA is puzzling, because according to our knowledge of Venus, no phosphine should be there. As the most plausible formation paths do not work, the source could be unknown chemical processes—maybe even life?
- Published
- 2020
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