Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra
Attempts to probe the atmospheres of rocky planets around M dwarfs present both promise and peril. While their favorable planet-to-star radius ratios enable searches for even thin secondary atmospheres, their high activity levels and high-energy outputs threaten atmosphere survival. Here we present...
Saved in:
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/ada381 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1841542657049886720 |
|---|---|
| author | Michael Radica Caroline Piaulet-Ghorayeb Jake Taylor Louis-Philippe Coulombe Björn Benneke Loic Albert Étienne Artigau Nicolas B. Cowan René Doyon David Lafrenière Alexandrine L’Heureux Olivia Lim |
| author_facet | Michael Radica Caroline Piaulet-Ghorayeb Jake Taylor Louis-Philippe Coulombe Björn Benneke Loic Albert Étienne Artigau Nicolas B. Cowan René Doyon David Lafrenière Alexandrine L’Heureux Olivia Lim |
| author_sort | Michael Radica |
| collection | DOAJ |
| description | Attempts to probe the atmospheres of rocky planets around M dwarfs present both promise and peril. While their favorable planet-to-star radius ratios enable searches for even thin secondary atmospheres, their high activity levels and high-energy outputs threaten atmosphere survival. Here we present the 0.6–2.85 μ m transmission spectrum of the 1.1 R _⊕ , ∼ 340 K rocky planet TRAPPIST-1 c obtained over two JWST NIRISS/SOSS transit observations. Each of the two spectra displays 100–500 ppm signatures of stellar contamination. Despite being separated by 367 days, the retrieved spot and facula properties are consistent between the two visits, resulting in nearly identical transmission spectra. Jointly retrieving for stellar contamination and a planetary atmosphere reveals that our spectrum can rule out hydrogen-dominated, ≲300× solar metallicity atmospheres with effective surface pressures down to 10 mbar at the 3 σ level. For high mean molecular weight atmospheres, where O _2 or N _2 is the background gas, our spectrum disfavors partial pressures of more than ∼10 mbar for H _2 O, CO, NH _3 , and CH _4 at the 2 σ level. Similarly, under the assumption of a 100% H _2 O, NH _3 , CO, or CH _4 atmosphere, our spectrum disfavors thick, >1-bar atmospheres at the 2 σ level. These nondetections of spectral features are in line with predictions that even heavier, CO _2 -rich atmospheres would be efficiently lost on TRAPPIST-1 c given the cumulative high-energy irradiation experienced by the planet. Our results further stress the importance of robustly accounting for stellar contamination when analyzing JWST observations of exo-Earths around M dwarfs, as well as the need for high-fidelity stellar models to search for the potential signals of thin secondary atmospheres. |
| format | Article |
| id | doaj-art-469e1d15945d4cddbd4349dccf2408e7 |
| institution | Kabale University |
| issn | 2041-8205 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj-art-469e1d15945d4cddbd4349dccf2408e72025-01-13T17:12:34ZengIOP PublishingThe Astrophysical Journal Letters2041-82052025-01-019791L510.3847/2041-8213/ada381Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission SpectraMichael Radica0https://orcid.org/0000-0002-3328-1203Caroline Piaulet-Ghorayeb1https://orcid.org/0000-0002-2875-917XJake Taylor2https://orcid.org/0000-0003-4844-9838Louis-Philippe Coulombe3https://orcid.org/0000-0002-2195-735XBjörn Benneke4https://orcid.org/0000-0001-5578-1498Loic Albert5https://orcid.org/0000-0003-0475-9375Étienne Artigau6https://orcid.org/0000-0003-3506-5667Nicolas B. Cowan7https://orcid.org/0000-0001-6129-5699René Doyon8https://orcid.org/0000-0001-5485-4675David Lafrenière9https://orcid.org/0000-0002-6780-4252Alexandrine L’Heureux10https://orcid.org/0009-0005-6135-6769Olivia Lim11https://orcid.org/0000-0003-4676-0622Department of Astronomy & Astrophysics, University of Chicago , 5640 South Ellis Avenue, Chicago, IL 60637, USA ; radicamc@uchicago.edu; Institut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaDepartment of Astronomy & Astrophysics, University of Chicago , 5640 South Ellis Avenue, Chicago, IL 60637, USA ; radicamc@uchicago.edu; Institut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaDepartment of Physics, University of Oxford , Parks Rd., Oxford OX1 3PU, UKInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada; Observatoire du Mont-Mégantic, Université de Montréal , Montréal, QC H3C 3J7, CanadaDepartment of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada; Department of Earth and Planetary Sciences, McGill University , 3600 rue University, Montréal, QC H3A 2T8, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada; Observatoire du Mont-Mégantic, Université de Montréal , Montréal, QC H3C 3J7, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaInstitut Trottier de Recherche sur les Exoplanètes and Département de Physique, Université de Montréal , 1375 Avenue Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, CanadaAttempts to probe the atmospheres of rocky planets around M dwarfs present both promise and peril. While their favorable planet-to-star radius ratios enable searches for even thin secondary atmospheres, their high activity levels and high-energy outputs threaten atmosphere survival. Here we present the 0.6–2.85 μ m transmission spectrum of the 1.1 R _⊕ , ∼ 340 K rocky planet TRAPPIST-1 c obtained over two JWST NIRISS/SOSS transit observations. Each of the two spectra displays 100–500 ppm signatures of stellar contamination. Despite being separated by 367 days, the retrieved spot and facula properties are consistent between the two visits, resulting in nearly identical transmission spectra. Jointly retrieving for stellar contamination and a planetary atmosphere reveals that our spectrum can rule out hydrogen-dominated, ≲300× solar metallicity atmospheres with effective surface pressures down to 10 mbar at the 3 σ level. For high mean molecular weight atmospheres, where O _2 or N _2 is the background gas, our spectrum disfavors partial pressures of more than ∼10 mbar for H _2 O, CO, NH _3 , and CH _4 at the 2 σ level. Similarly, under the assumption of a 100% H _2 O, NH _3 , CO, or CH _4 atmosphere, our spectrum disfavors thick, >1-bar atmospheres at the 2 σ level. These nondetections of spectral features are in line with predictions that even heavier, CO _2 -rich atmospheres would be efficiently lost on TRAPPIST-1 c given the cumulative high-energy irradiation experienced by the planet. Our results further stress the importance of robustly accounting for stellar contamination when analyzing JWST observations of exo-Earths around M dwarfs, as well as the need for high-fidelity stellar models to search for the potential signals of thin secondary atmospheres.https://doi.org/10.3847/2041-8213/ada381Low mass starsExoplanet atmospheresExtrasolar rocky planetsPlanetary atmospheresExoplanets |
| spellingShingle | Michael Radica Caroline Piaulet-Ghorayeb Jake Taylor Louis-Philippe Coulombe Björn Benneke Loic Albert Étienne Artigau Nicolas B. Cowan René Doyon David Lafrenière Alexandrine L’Heureux Olivia Lim Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra The Astrophysical Journal Letters Low mass stars Exoplanet atmospheres Extrasolar rocky planets Planetary atmospheres Exoplanets |
| title | Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra |
| title_full | Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra |
| title_fullStr | Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra |
| title_full_unstemmed | Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra |
| title_short | Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1 c from JWST NIRISS Transmission Spectra |
| title_sort | promise and peril stellar contamination and strict limits on the atmosphere composition of trappist 1 c from jwst niriss transmission spectra |
| topic | Low mass stars Exoplanet atmospheres Extrasolar rocky planets Planetary atmospheres Exoplanets |
| url | https://doi.org/10.3847/2041-8213/ada381 |
| work_keys_str_mv | AT michaelradica promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT carolinepiauletghorayeb promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT jaketaylor promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT louisphilippecoulombe promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT bjornbenneke promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT loicalbert promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT etienneartigau promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT nicolasbcowan promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT renedoyon promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT davidlafreniere promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT alexandrinelheureux promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra AT olivialim promiseandperilstellarcontaminationandstrictlimitsontheatmospherecompositionoftrappist1cfromjwstnirisstransmissionspectra |