Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b
Hot Jupiters are among the best-studied exoplanets, but it is still poorly understood how their chemical composition and cloud properties vary with longitude. Theoretical models predict that clouds may condense on the nightside and that molecular abundances can be driven out of equilibrium by zonal...
Principais autores: | , , , , , , , , , , , , , , , , , , , , , , , , , |
---|---|
Formato: | Journal article |
Idioma: | English |
Publicado em: |
Nature Research
2024
|
_version_ | 1826313730275672064 |
---|---|
author | Bell, TJ Crouzet, N Cubillos, PE Kreidberg, L Piette, AAA Roman, MT Barstow, JK Blecic, J Carone, L Coulombe, L Ducrot, E Hammond, M Mendonça, JM Moses, JI Parmentier, V Stevenson, KB Teinturier, L Zhang, M Batalha, NM Bean, JL Benneke, B Charnay, B Chubb, KL Demory, B Tan, X Taylor, J |
author_facet | Bell, TJ Crouzet, N Cubillos, PE Kreidberg, L Piette, AAA Roman, MT Barstow, JK Blecic, J Carone, L Coulombe, L Ducrot, E Hammond, M Mendonça, JM Moses, JI Parmentier, V Stevenson, KB Teinturier, L Zhang, M Batalha, NM Bean, JL Benneke, B Charnay, B Chubb, KL Demory, B Tan, X Taylor, J |
author_sort | Bell, TJ |
collection | OXFORD |
description | Hot Jupiters are among the best-studied exoplanets, but it is still poorly understood how their chemical composition and cloud properties vary with longitude. Theoretical models predict that clouds may condense on the nightside and that molecular abundances can be driven out of equilibrium by zonal winds. Here we report a phase-resolved emission spectrum of the hot Jupiter WASP-43b measured from 5 μm to 12 μm with the JWST’s Mid-Infrared Instrument. The spectra reveal a large day–night temperature contrast (with average brightness temperatures of 1,524 ± 35 K and 863 ± 23 K, respectively) and evidence for water absorption at all orbital phases. Comparisons with three-dimensional atmospheric models show that both the phase-curve shape and emission spectra strongly suggest the presence of nightside clouds that become optically thick to thermal emission at pressures greater than ~100 mbar. The dayside is consistent with a cloudless atmosphere above the mid-infrared photosphere. Contrary to expectations from equilibrium chemistry but consistent with disequilibrium kinetics models, methane is not detected on the nightside (2σ upper limit of 1–6 ppm, depending on model assumptions). Our results provide strong evidence that the atmosphere of WASP-43b is shaped by disequilibrium processes and provide new insights into the properties of the planet’s nightside clouds. However, the remaining discrepancies between our observations and our predictive atmospheric models emphasize the importance of further exploring the effects of clouds and disequilibrium chemistry in numerical models. |
first_indexed | 2024-09-25T04:21:10Z |
format | Journal article |
id | oxford-uuid:d22a737d-fe11-41e7-908c-d10e9d5da8dc |
institution | University of Oxford |
language | English |
last_indexed | 2024-09-25T04:21:10Z |
publishDate | 2024 |
publisher | Nature Research |
record_format | dspace |
spelling | oxford-uuid:d22a737d-fe11-41e7-908c-d10e9d5da8dc2024-08-02T19:34:17ZNightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43bJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:d22a737d-fe11-41e7-908c-d10e9d5da8dcEnglishJisc Publications RouterNature Research2024Bell, TJCrouzet, NCubillos, PEKreidberg, LPiette, AAARoman, MTBarstow, JKBlecic, JCarone, LCoulombe, LDucrot, EHammond, MMendonça, JMMoses, JIParmentier, VStevenson, KBTeinturier, LZhang, MBatalha, NMBean, JLBenneke, BCharnay, BChubb, KLDemory, BTan, XTaylor, JHot Jupiters are among the best-studied exoplanets, but it is still poorly understood how their chemical composition and cloud properties vary with longitude. Theoretical models predict that clouds may condense on the nightside and that molecular abundances can be driven out of equilibrium by zonal winds. Here we report a phase-resolved emission spectrum of the hot Jupiter WASP-43b measured from 5 μm to 12 μm with the JWST’s Mid-Infrared Instrument. The spectra reveal a large day–night temperature contrast (with average brightness temperatures of 1,524 ± 35 K and 863 ± 23 K, respectively) and evidence for water absorption at all orbital phases. Comparisons with three-dimensional atmospheric models show that both the phase-curve shape and emission spectra strongly suggest the presence of nightside clouds that become optically thick to thermal emission at pressures greater than ~100 mbar. The dayside is consistent with a cloudless atmosphere above the mid-infrared photosphere. Contrary to expectations from equilibrium chemistry but consistent with disequilibrium kinetics models, methane is not detected on the nightside (2σ upper limit of 1–6 ppm, depending on model assumptions). Our results provide strong evidence that the atmosphere of WASP-43b is shaped by disequilibrium processes and provide new insights into the properties of the planet’s nightside clouds. However, the remaining discrepancies between our observations and our predictive atmospheric models emphasize the importance of further exploring the effects of clouds and disequilibrium chemistry in numerical models. |
spellingShingle | Bell, TJ Crouzet, N Cubillos, PE Kreidberg, L Piette, AAA Roman, MT Barstow, JK Blecic, J Carone, L Coulombe, L Ducrot, E Hammond, M Mendonça, JM Moses, JI Parmentier, V Stevenson, KB Teinturier, L Zhang, M Batalha, NM Bean, JL Benneke, B Charnay, B Chubb, KL Demory, B Tan, X Taylor, J Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b |
title | Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b |
title_full | Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b |
title_fullStr | Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b |
title_full_unstemmed | Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b |
title_short | Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b |
title_sort | nightside clouds and disequilibrium chemistry on the hot jupiter wasp 43b |
work_keys_str_mv | AT belltj nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT crouzetn nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT cubillospe nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT kreidbergl nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT pietteaaa nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT romanmt nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT barstowjk nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT blecicj nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT caronel nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT coulombel nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT ducrote nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT hammondm nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT mendoncajm nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT mosesji nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT parmentierv nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT stevensonkb nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT teinturierl nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT zhangm nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT batalhanm nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT beanjl nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT bennekeb nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT charnayb nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT chubbkl nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT demoryb nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT tanx nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b AT taylorj nightsidecloudsanddisequilibriumchemistryonthehotjupiterwasp43b |