Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e
Ongoing observing projects like the James Webb Space Telescope and future missions offer the chance to characterize Earth-like exoplanetary atmospheres. Thereby, M dwarfs are preferred targets for transit observations, for example, due to their favorable planet–star contrast ratio. However, the radi...
| Main Authors: | , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2024-01-01
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| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/ad0895 |
| _version_ | 1797348214979952640 |
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| author | Konstantin Herbst Andreas Bartenschlager John Lee Grenfell Nicolas Iro Miriam Sinnhuber Benjamin Taysum Fabian Wunderlich N. Eugene Engelbrecht Juandre Light Katlego D. Moloto Jan-Vincent Harre Heike Rauer Franz Schreier |
| author_facet | Konstantin Herbst Andreas Bartenschlager John Lee Grenfell Nicolas Iro Miriam Sinnhuber Benjamin Taysum Fabian Wunderlich N. Eugene Engelbrecht Juandre Light Katlego D. Moloto Jan-Vincent Harre Heike Rauer Franz Schreier |
| author_sort | Konstantin Herbst |
| collection | DOAJ |
| description | Ongoing observing projects like the James Webb Space Telescope and future missions offer the chance to characterize Earth-like exoplanetary atmospheres. Thereby, M dwarfs are preferred targets for transit observations, for example, due to their favorable planet–star contrast ratio. However, the radiation and particle environment of these cool stars could be far more extreme than what we know from the Sun. Thus, knowing the stellar radiation and particle environment and its possible influence on detectable biosignatures—in particular, signs of life like ozone and methane—is crucial to understanding upcoming transit spectra. In this study, with the help of our unique model suite INCREASE, we investigate the impact of a strong stellar energetic particle event on the atmospheric ionization, neutral and ion chemistry, and atmospheric biosignatures of TRAPPIST-1e. Therefore, transit spectra for six scenarios are simulated. We find that a Carrington-like event drastically increases atmospheric ionization and induces substantial changes in ion chemistry and spectral transmission features: all scenarios show high event-induced amounts of nitrogen dioxide (i.e., at 6.2 μ m), a reduction of the atmospheric transit depth in all water bands (i.e., at 5.5–7.0 μ m), a decrease of the methane bands (i.e., at 3.0–3.5 μ m), and depletion of ozone (i.e., at ∼9.6 μ m). Therefore, it is essential to include high-energy particle effects to correctly assign biosignature signals from, e.g., ozone and methane. We further show that the nitric acid feature at 11.0–12.0 μ m, discussed as a proxy for stellar particle contamination, is absent in wet-dead atmospheres. |
| first_indexed | 2024-03-08T12:02:31Z |
| format | Article |
| id | doaj.art-506b299b0d18462aa480161010beb2e9 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-08T12:02:31Z |
| publishDate | 2024-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-506b299b0d18462aa480161010beb2e92024-01-23T18:23:57ZengIOP PublishingThe Astrophysical Journal1538-43572024-01-01961216410.3847/1538-4357/ad0895Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1eKonstantin Herbst0https://orcid.org/0000-0001-5622-4829Andreas Bartenschlager1https://orcid.org/0000-0002-8631-7572John Lee Grenfell2https://orcid.org/0000-0003-3646-5339Nicolas Iro3https://orcid.org/0000-0003-2329-418XMiriam Sinnhuber4https://orcid.org/0000-0002-3527-9051Benjamin Taysum5https://orcid.org/0000-0002-0856-4340Fabian Wunderlich6https://orcid.org/0000-0002-2238-5269N. Eugene Engelbrecht7https://orcid.org/0000-0003-3659-7956Juandre Light8https://orcid.org/0000-0002-9788-5540Katlego D. Moloto9https://orcid.org/0000-0002-4840-6355Jan-Vincent Harre10https://orcid.org/0000-0001-8935-2472Heike Rauer11https://orcid.org/0000-0002-6510-1828Franz Schreier12https://orcid.org/0000-0001-7196-6599Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , D-24118 Kiel, Germany ; herbst@physik.uni-kiel.deInstitut für Meteorologie und Klimaforschung, Karlsruher Institut für Technologie , D-76344 Eggenstein-Leopoldshafen, GermanyInstitut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-12489 Berlin, GermanyInstitut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-12489 Berlin, GermanyInstitut für Meteorologie und Klimaforschung, Karlsruher Institut für Technologie , D-76344 Eggenstein-Leopoldshafen, GermanyInstitut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-12489 Berlin, GermanyInstitut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-12489 Berlin, GermanyCentre for Space Research, North-West University , 2520, Potchefstroom, South AfricaCentre for Space Research, North-West University , 2520, Potchefstroom, South Africa; South African National Space Agency , Hermanus, South AfricaCentre for Space Research, North-West University , 2520, Potchefstroom, South AfricaInstitut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-12489 Berlin, GermanyInstitut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-12489 Berlin, Germany; Institut für Geologische Wissenschaften, Freie Universität Berlin , D-12249 Berlin, GermanyInstitut für Methodik der Fernerkundung, Deutsches Zentrum für Luft- und Raumfahrt (DLR) , D-82234 Oberpfaffenhofen, GermanyOngoing observing projects like the James Webb Space Telescope and future missions offer the chance to characterize Earth-like exoplanetary atmospheres. Thereby, M dwarfs are preferred targets for transit observations, for example, due to their favorable planet–star contrast ratio. However, the radiation and particle environment of these cool stars could be far more extreme than what we know from the Sun. Thus, knowing the stellar radiation and particle environment and its possible influence on detectable biosignatures—in particular, signs of life like ozone and methane—is crucial to understanding upcoming transit spectra. In this study, with the help of our unique model suite INCREASE, we investigate the impact of a strong stellar energetic particle event on the atmospheric ionization, neutral and ion chemistry, and atmospheric biosignatures of TRAPPIST-1e. Therefore, transit spectra for six scenarios are simulated. We find that a Carrington-like event drastically increases atmospheric ionization and induces substantial changes in ion chemistry and spectral transmission features: all scenarios show high event-induced amounts of nitrogen dioxide (i.e., at 6.2 μ m), a reduction of the atmospheric transit depth in all water bands (i.e., at 5.5–7.0 μ m), a decrease of the methane bands (i.e., at 3.0–3.5 μ m), and depletion of ozone (i.e., at ∼9.6 μ m). Therefore, it is essential to include high-energy particle effects to correctly assign biosignature signals from, e.g., ozone and methane. We further show that the nitric acid feature at 11.0–12.0 μ m, discussed as a proxy for stellar particle contamination, is absent in wet-dead atmospheres.https://doi.org/10.3847/1538-4357/ad0895BiosignaturesExoplanet atmospheric compositionExtrasolar rocky planetsCosmic rays |
| spellingShingle | Konstantin Herbst Andreas Bartenschlager John Lee Grenfell Nicolas Iro Miriam Sinnhuber Benjamin Taysum Fabian Wunderlich N. Eugene Engelbrecht Juandre Light Katlego D. Moloto Jan-Vincent Harre Heike Rauer Franz Schreier Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e The Astrophysical Journal Biosignatures Exoplanet atmospheric composition Extrasolar rocky planets Cosmic rays |
| title | Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e |
| title_full | Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e |
| title_fullStr | Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e |
| title_full_unstemmed | Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e |
| title_short | Impact of Cosmic Rays on Atmospheric Ion Chemistry and Spectral Transmission Features of TRAPPIST-1e |
| title_sort | impact of cosmic rays on atmospheric ion chemistry and spectral transmission features of trappist 1e |
| topic | Biosignatures Exoplanet atmospheric composition Extrasolar rocky planets Cosmic rays |
| url | https://doi.org/10.3847/1538-4357/ad0895 |
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