Details

Autor(en) / Beteiligte

• Beatty, Thomas G.
• Welbanks, Luis
• Schlawin, Everett
• Bell, Taylor J.
• Line, Michael R.
• Murphy, Matthew
• Edelman, Isaac
• Greene, Thomas P.
• Fortney, Jonathan J.
• Henry, Gregory W.
• Mukherjee, Sagnick
• Ohno, Kazumasa
• Parmentier, Vivien
• Rauscher, Emily
• Wiser, Lindsey S.
• Arnold, Kenneth E.

Titel

Sulfur Dioxide and Other Molecular Species in the Atmosphere of the Sub-Neptune GJ 3470 b

Ist Teil von

• Astrophysical journal. Letters, 2024-07, Vol.970 (1), p.L10

Ort / Verlag

Austin: The American Astronomical Society

Erscheinungsjahr

2024

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Abstract We report observations of the atmospheric transmission spectrum of the sub-Neptune exoplanet GJ 3470 b taken using the Near-Infrared Camera on JWST. Combined with two archival Hubble Space Telescope/Wide-Field Camera 3 transit observations and 15 archival Spitzer transit observations, we detect water, methane, sulfur dioxide, and carbon dioxide in the atmosphere of GJ 3470 b, each with a significance of >3 σ . GJ 3470 b is the lowest-mass—and coldest—exoplanet known to show a substantial sulfur dioxide feature in its spectrum, at M p = 11.2 M ⊕ and T eq = 600 K. This indicates that disequilibrium photochemistry drives sulfur dioxide production in exoplanet atmospheres over a wider range of masses and temperatures than has been reported or expected. The water, carbon dioxide, and sulfur dioxide abundances we measure indicate an atmospheric metallicity of approximately 100× solar. We see further evidence for disequilibrium chemistry in our inferred methane abundance, which is significantly lower than expected from equilibrium models consistent with our measured water and carbon dioxide abundances.