TY - JOUR
T1 - SO$_2$, silicate clouds, but no CH$_4$ detected in a warm Neptune
AU - Dyrek, Achrène
AU - Min, Michiel
AU - Decin, Leen
AU - Bouwman, Jeroen
AU - Crouzet, Nicolas
AU - Mollière, Paul
AU - Lagage, Pierre-Olivier
AU - Konings, Thomas
AU - Tremblin, Pascal
AU - Güdel, Manuel
AU - Pye, John
AU - Waters, Rens
AU - Henning, Thomas
AU - Vandenbussche, Bart
AU - Ardevol Martinez, Francisco
AU - Argyriou, Ioannis
AU - Ducrot, Elsa
AU - Heinke, Linus
AU - Van Looveren, Gwenael
AU - Absil, Olivier
AU - Barrado, David
AU - Baudoz, Pierre
AU - Boccaletti, Anthony
AU - Cossou, Christophe
AU - Coulais, Alain
AU - Edwards, Billy
AU - Gastaud, René
AU - Glasse, Alistair
AU - Glauser, Adrian
AU - Greene, Thomas P.
AU - Kendrew, Sarah
AU - Krause, Oliver
AU - Lahuis, Fred
AU - Mueller, Michael
AU - Olofsson, Goran
AU - Patapis, Polychronis
AU - Rouan, Daniel
AU - Royer, Pierre
AU - Scheithauer, Silvia
AU - Waldmann, Ingo
AU - Whiteford, Niall
AU - Colina, Luis
AU - van Dishoeck, Ewine F.
AU - Ostlin, Göran
AU - Ray, Tom P.
AU - Wright, Gillian
N1 - Publisher Copyright:
© 2023, The Author(s), under exclusive licence to Springer Nature Limited.
PY - 2024/1/1
Y1 - 2024/1/1
N2 - WASP-107b is a warm (approximately 740 K) transiting planet with a Neptune-like mass of roughly 30.5 M
⊕ and Jupiter-like radius of about 0.94 R
J (refs.
1,2), whose extended atmosphere is eroding
3. Previous observations showed evidence for water vapour and a thick, high-altitude condensate layer in the atmosphere of WASP-107b (refs.
4,5). Recently, photochemically produced sulfur dioxide (SO
2) was detected in the atmosphere of a hot (about 1,200 K) Saturn-mass planet from transmission spectroscopy near 4.05 μm (refs.
6,7), but for temperatures below about 1,000 K, sulfur is predicted to preferably form sulfur allotropes instead of SO
2 (refs.
8–10). Here we report the 9σ detection of two fundamental vibration bands of SO
2, at 7.35 μm and 8.69 μm, in the transmission spectrum of WASP-107b using the Mid-Infrared Instrument (MIRI) of JWST. This discovery establishes WASP-107b as the second irradiated exoplanet with confirmed photochemistry, extending the temperature range of exoplanets exhibiting detected photochemistry from about 1,200 K down to about 740 K. Furthermore, our spectral analysis reveals the presence of silicate clouds, which are strongly favoured (around 7σ) over simpler cloud set-ups. Furthermore, water is detected (around 12σ) but methane is not. These findings provide evidence of disequilibrium chemistry and indicate a dynamically active atmosphere with a super-solar metallicity.
AB - WASP-107b is a warm (approximately 740 K) transiting planet with a Neptune-like mass of roughly 30.5 M
⊕ and Jupiter-like radius of about 0.94 R
J (refs.
1,2), whose extended atmosphere is eroding
3. Previous observations showed evidence for water vapour and a thick, high-altitude condensate layer in the atmosphere of WASP-107b (refs.
4,5). Recently, photochemically produced sulfur dioxide (SO
2) was detected in the atmosphere of a hot (about 1,200 K) Saturn-mass planet from transmission spectroscopy near 4.05 μm (refs.
6,7), but for temperatures below about 1,000 K, sulfur is predicted to preferably form sulfur allotropes instead of SO
2 (refs.
8–10). Here we report the 9σ detection of two fundamental vibration bands of SO
2, at 7.35 μm and 8.69 μm, in the transmission spectrum of WASP-107b using the Mid-Infrared Instrument (MIRI) of JWST. This discovery establishes WASP-107b as the second irradiated exoplanet with confirmed photochemistry, extending the temperature range of exoplanets exhibiting detected photochemistry from about 1,200 K down to about 740 K. Furthermore, our spectral analysis reveals the presence of silicate clouds, which are strongly favoured (around 7σ) over simpler cloud set-ups. Furthermore, water is detected (around 12σ) but methane is not. These findings provide evidence of disequilibrium chemistry and indicate a dynamically active atmosphere with a super-solar metallicity.
KW - Astrophysics - Earth and Planetary Astrophysics
KW - Astrophysics - Instrumentation and Methods for Astrophysics
UR - http://www.scopus.com/inward/record.url?scp=85180250085&partnerID=8YFLogxK
U2 - 10.1038/s41586-023-06849-0
DO - 10.1038/s41586-023-06849-0
M3 - Article
SN - 0028-0836
VL - 625
SP - 51
EP - 54
JO - Nature
JF - Nature
IS - 7993
ER -