Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets
| العنوان: | Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets |
|---|---|
| المؤلفون: | Hanno Rein, Yuka Fujii, David S. Spiegel |
| المصدر: | Proceedings of the National Academy of Sciences of the United States of America. 111(19):6871-6875 |
| سنة النشر: | 2014 |
| مصطلحات موضوعية: | Extraterrestrial Environment, Earth, Planet, Astronomy, Disequilibrium, FOS: Physical sciences, Planets, Astrobiology, Planet, Biosignature, Exobiology, medicine, Moon, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Physics, Earth and Planetary Astrophysics (astro-ph.EP), Multidisciplinary, Atmosphere, Spectrum Analysis, Exomoon, Water, Models, Theoretical, Exoplanet, Earth analog, Chemical species, Astrophysics - Solar and Stellar Astrophysics, Physics::Space Physics, Physical Sciences, Astrophysics::Earth and Planetary Astrophysics, medicine.symptom, Astrophysics - Instrumentation and Methods for Astrophysics, Evolution, Planetary, Astrophysics - Earth and Planetary Astrophysics |
| الوصف: | The detection of strong thermochemical disequilibrium in the atmosphere of an extrasolar planet is thought to be a potential biosignature. In this article we present a new kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species. We consider a scenario where the exoplanet hosts a moon that has its own atmosphere and neither of the atmospheres is in chemical disequilibrium. Our results show that the integrated spectrum of the planet and the moon closely resembles that of a single object in strong chemical disequilibrium. We derive a firm limit on the maximum spectral resolution that can be obtained for both directly-imaged and transiting planets. The spectral resolution of even idealized space-based spectrographs that might be achievable in the next several decades is in general insufficient to break the degeneracy. Both chemical species can only be definitively confirmed in the same object if absorption features of both chemicals can be unambiguously identified and their combined depth exceeds 100%. Comment: Accepted for publication in the Proceedings of the National Academy of Sciences (PNAS), 6 pages, 3 figures |
| اللغة: | English |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e985a6ca5b3ca3a79e1ccae4f1f03155 http://t2r2.star.titech.ac.jp/cgi-bin/publicationinfo.cgi?q_publication_content_number=CTT100804337 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....e985a6ca5b3ca3a79e1ccae4f1f03155 |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |