Observation of undepleted phosphine in the atmosphere of a low-temperature brown dwarf

• 成果类型: Article
• 署名作者: Burgasser, Adam J.; Gonzales, Eileen C.; Beiler, Samuel A.; Visscher, Channon; Burningham, Ben; Mace, Gregory N.; Faherty, Jacqueline K.; Zhang, Zenghua; Sousa-Silva, Clara; Lodieu, Nicolas; Metchev, Stanimir A.; Meisner, Aaron; Cushing, Michael; Schneider, Adam C.; Suarez, Genaro; Hsu, Chih-Chun; Gerasimov, Roman; Aganze, Christian; Theissen, Christopher A.
• 署名单位: University of California System; University of California San Diego; California State University System; San Francisco State University; University System of Ohio; University of Toledo; University of Hertfordshire; University of Texas System; University of Texas Austin; American Museum of Natural History (AMNH); Nanjing University; Nanjing University; Universidade do Porto; Instituto de Astrofisica de Canarias; Universidad de la Laguna; Instituto de Astrofisica de Canarias; Western University (University of Western Ontario); Western University (University of Western Ontario); National Science Foundation (NSF); Northwestern University; University of Notre Dame; Stanford University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8075; 1095-9203
• DOI: 10.1126/science.adu0401
• 发表日期: 2025-11-13
• 页码: 697-701
• 关键词: CHEMICAL EVOLUTION; giant planets; LATE-T; chemistry; stars; PH3; phosphorus; spectrum; jupiter; disequilibrium

摘要

The atmospheres of low-temperature brown dwarfs and gas giant planets are expected to contain the phosphine molecule, PH3. However, previous observations have shown much lower abundances of this molecule than predicted with atmospheric chemistry models. We report JWST spectroscopic observations of phosphine in the atmosphere of the brown dwarf Wolf 1130C. Multiple absorption lines due to phosphine have been detected around 4.3 micrometers, from which we calculated a phosphine abundance of 0.100 +/- 0.009 parts per million. This abundance is consistent with disequilibrium atmospheric chemistry models that reproduced the phosphine abundances in Jupiter and Saturn and is much higher than abundances previously reported for other brown dwarfs or exoplanets. This difference may be related to the low abundance of elements heavier than helium in Wolf 1130C.