Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b
Artikel i vetenskaplig tidskrift, 2024

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.

Författare

Taylor Bell

NASA Ames Research Center

N. Crouzet

Universiteit Leiden

P. E. Cubillos

Institut fur Weltraumforschung

Istituto nazionale di astrofisica (INAF)

L. Kreidberg

Max-Planck-Gesellschaft

Anjali A.A. Piette

Carnegie Institution of Washington

Michael T. Roman

Universidad Adolfo Ibanez

University Of Leicester

J. Barstow

Open University

Jasmina Blecic

New York University Abu Dhabi

L. Carone

Institut fur Weltraumforschung

Louis Philippe Coulombe

Université de Montréal

E. Ducrot

Université Paris-Saclay

Mark Hammond

University of Oxford

João M. Mendonça

Danmarks Tekniske Universitet (DTU)

Julianne I. Moses

Space Science Institute

Vivien Parmentier

Observatoire de la Cote d'Azur

Kevin B. Stevenson

The Johns Hopkins University Applied Physics Laboratory

Lucas Teinturier

Observatoire de Paris

Université Pierre et Marie Curie (UPMC)

Michael Zhang

University of Chicago

Natalie Batalha

University of California

Jacob L. Bean

University of Chicago

B. Benneke

Université de Montréal

Bejamin Charnay

Observatoire de Paris

Katy L. Chubb

University of St Andrews

B.O. Demory

Physics Institute

Universität Bern

Peter Gao

Carnegie Institution of Washington

Elspeth K.H. Lee

Universität Bern

Mercedes López-Morales

Harvard-Smithsonian Center for Astrophysics

Giuseppe Morello

Istituto nazionale di astrofisica (INAF)

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Instituto de Astrofísica de Canarias

Emily Rauscher

University of Michigan

David K. Sing

Johns Hopkins University

Xianyu Tan

Shanghai Jiao Tong University

University of Oxford

Olivia Venot

Université Paris-Est Créteil Val de Marne

Hannah R. Wakeford

University of Bristol

Keshav Aggarwal

Indian Institute of Technology

Eva Maria Ahrer

The University of Warwick

Munazza K. Alam

Carnegie Institution of Washington

Robin Baeyens

Anton Pannekoek Institute for Astronomy

D. Barrado

European Space Astronomy Centre (ESAC)

Claudio Caceres

Universidad Andrés Bello

Núcleo Milenio de Formación Planetaria (NPF)

Centro de Astrofísica y Tecnologías Afines (CATA),

Aarynn L. Carter

University of California

Sarah Casewell

University Of Leicester

Ryan C. Challener

University of Michigan

I. J.M. Crossfield

University of Kansas

L. Decin

KU Leuven

J. M. Desert

Anton Pannekoek Institute for Astronomy

Ian Dobbs-Dixon

New York University Abu Dhabi

A. Dyrek

Université Paris-Saclay

Néstor Espinoza

Space Telescope Science Institute (STScI)

Johns Hopkins University

A. D. Feinstein

University of Colorado at Boulder

University of Chicago

Neale P. Gibson

Trinity College Dublin

Joseph Harrington

University of Central Florida

Ch. Helling

Institut fur Weltraumforschung

Renyu Hu

California Institute of Technology (Caltech)

Nicolas Iro

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Eliza M.R. Kempton

University of Maryland

S. Kendrew

Europeiska rymdorganisationen (ESA)

Thaddeus D. Komacek

University of Maryland

Jessica Krick

California Institute of Technology (Caltech)

P. O. Lagage

Université Paris-Saclay

J. Leconte

Laboratoire d'Astrophysique de Bordeaux

M. Lendl

Université de Genève

Neil T. Lewis

University of Exeter

Joshua D. Lothringer

Utah Valley University

Isaac Malsky

University of Michigan

Luigi Mancini

Universita degli Studi di Roma Tor Vergata

Max-Planck-Gesellschaft

Istituto nazionale di astrofisica (INAF)

Megan Mansfield

University of Arizona

Nathan J. Mayne

University of Exeter

Thomas M. Evans-Soma

Max-Planck-Gesellschaft

University of Newcastle

K. Molaverdikhani

Ludwig-Maximilians-Universität München (LMU)

Nikolay K. Nikolov

Space Telescope Science Institute (STScI)

M. C. Nixon

University of Maryland

Enric Palle

Instituto de Astrofísica de Canarias

Dominique J.M. Petit dit de la Roche

Université de Genève

Caroline Piaulet

Université de Montréal

Diana Powell

Harvard-Smithsonian Center for Astrophysics

Benjamin V. Rackham

Massachusetts Institute of Technology (MIT)

Aaron D. Schneider

KU Leuven

Niels Bohr Institute

Maria E. Steinrueck

Max-Planck-Gesellschaft

Jake Taylor

University of Oxford

Université de Montréal

Luis Welbanks

Arizona State University

Sergey N. Yurchenko

University College London (UCL)

Xi Zhang

University of California

Sebastian Zieba

Max-Planck-Gesellschaft

Universiteit Leiden

Nature Astronomy

23973366 (eISSN)

Vol. In Press

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.1038/s41550-024-02230-x

Mer information

Senast uppdaterat

2024-05-29