The hot dayside and asymmetric transit of WASP-189 b seen by CHEOPS
Artikel i vetenskaplig tidskrift, 2020
The CHEOPS space mission dedicated to exoplanet follow-up was launched in December 2019, equipped with the capacity to perform photometric measurements at the 20 ppm level. As CHEOPS carries out its observations in a broad optical passband, it can provide insights into the reflected light from exoplanets and constrain the short-wavelength thermal emission for the hottest of planets by observing occultations and phase curves. Here, we report the first CHEOPS observation of an occultation, namely, that of the hot Jupiter WASP-189 b, a MP ≈ 2MJ planet orbiting an A-type star. We detected the occultation of WASP-189 b at high significance in individual measurements and derived an occultation depth of dF = 87.9 ± 4.3 ppm based on four occultations. We compared these measurements to model predictions and we find that they are consistent with an unreflective atmosphere heated to a temperature of 3435 ± 27 K, when assuming inefficient heat redistribution. Furthermore, we present two transits of WASP-189 b observed by CHEOPS. These transits have an asymmetric shape that we attribute to gravity darkening of the host star caused by its high rotation rate. We used these measurements to refine the planetary parameters, finding a ~25% deeper transit compared to the discovery paper and updating the radius of WASP-189 b to 1.619 ± 0.021RJ. We further measured the projected orbital obliquity to be λ = 86.4-4.4+2.9°, a value that is in good agreement with a previous measurement from spectroscopic observations, and derived a true obliquity of ψ = 85.4 ± 4.3°. Finally, we provide reference values for the photometric precision attained by the CHEOPS satellite: for the V = 6.6 mag star, and using a 1-h binning, we obtain a residual RMS between 10 and 17 ppm on the individual light curves, and 5.7 ppm when combining the four visits.
Planets and satellites: individual: WASP-189 b
Techniques: photometric
Planets and satellites: atmospheres
Författare
M. Lendl
Université de Genève
Szilard Csizmadia
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
A. Deline
Université de Genève
L. Fossati
Institut fur Weltraumforschung
D. Kitzmann
Universität Bern
Kevin Heng
Universität Bern
S. Hoyer
Laboratoire d'Astrophysique de Marseille
S. Salmon
Université de Genève
W. Benz
Universität Bern
C. Broeg
Universität Bern
D. Ehrenreich
Université de Genève
A. Fortier
Universität Bern
D. Queloz
Université de Genève
A. Bonfanti
Institut fur Weltraumforschung
A. Brandeker
Stockholms universitet
A. Collier Cameron
University of St Andrews
L. Delrez
Université de Genève
A. Garcia Munoz
Technische Universität Berlin
M.J. Hooton
Universität Bern
P. Maxted
Keele University
Brett M. Morris
Universität Bern
V. Van Grootel
Universite de Liège
T.G. Wilson
University of St Andrews
Y. Alibert
Universität Bern
R. Alonso
Instituto de Astrofísica de Canarias
J. Asquier
European Space Research and Technology Centre (ESA ESTEC)
T. Bandy
Universität Bern
T. Bárczy
Admatis
D. Barrado
Centro de Astrobiologia (CAB)
S.C.C. Barros
Universidade do Porto
W. Baumjohann
Institut fur Weltraumforschung
M. Beck
Université de Genève
T. Beck
Universität Bern
A. Bekkelien
Université de Genève
M. Bergomi
Istituto nazionale di astrofisica (INAF)
N. Billot
Université de Genève
F. Biondi
Istituto nazionale di astrofisica (INAF)
X. Bonfils
Université Grenoble Alpes
V. Bourrier
Université de Genève
M.-D. Busch
Universität Bern
J. Cabrera
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
V. Cessa
Universität Bern
S. Charnoz
Institut de Physique du Globe de Paris
B. Chazelas
Université de Genève
C. Corral Van Damme
European Space Research and Technology Centre (ESA ESTEC)
Melvyn B. Davies
Lunds universitet
M. Deleuil
Laboratoire d'Astrophysique de Marseille
O. Demangeon
Laboratoire d'Astrophysique de Marseille
B.O. Demory
Universität Bern
Anders Erikson
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
J. Farinato
Istituto nazionale di astrofisica (INAF)
Malcolm Fridlund
Universiteit Leiden
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
D. Futyan
Université de Genève
D. Gandolfi
Istituto nazionale di astrofisica (INAF)
Michaël Gillon
Universite de Liège
P. Guterman
Laboratoire d'Astrophysique de Marseille
J. Hasiba
Institut fur Weltraumforschung
E. Hernandez
Universität Bern
K. Isaak
European Space Research and Technology Centre (ESA ESTEC)
L.L. Kiss
Magyar Tudomanyos Akademia
T. Kuntzer
Université de Genève
A. L. des Etangs
Institut d 'Astrophysique de Paris
T. Lüftinger
Universität Wien
J. Laskar
Observatoire de Paris
C. Lovis
Université de Genève
D. Magrin
Istituto nazionale di astrofisica (INAF)
L. Malvasio
Universität Bern
L. Marafatto
Istituto nazionale di astrofisica (INAF)
H. Michaelis
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
M. Munari
Istituto nazionale di astrofisica (INAF)
Valerio Nascimbeni
Istituto nazionale di astrofisica (INAF)
G. Olofsson
Stockholms universitet
H. Ottacher
Institut fur Weltraumforschung
R. Ottensamer
Universität Wien
I. Pagano
Istituto nazionale di astrofisica (INAF)
E. Palle
Instituto de Astrofísica de Canarias
G. Peter
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
D. Piazza
Universität Bern
Giampaolo P. Piotto
Istituto nazionale di astrofisica (INAF)
Don L. Pollacco
The University of Warwick
F. Ratti
European Space Research and Technology Centre (ESA ESTEC)
H. Rauer
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
Roberto Ragazzoni
Istituto nazionale di astrofisica (INAF)
N. Rando
European Space Research and Technology Centre (ESA ESTEC)
I. Ribas
Institut de Ciències de l'Espai (ICE) - CSIC
M. Rieder
Universität Bern
R. Rohlfs
Université de Genève
F. Safa
European Space Research and Technology Centre (ESA ESTEC)
N. C. Santos
Universidade do Porto
Gaetano Scandariato
Istituto nazionale di astrofisica (INAF)
D. Segransan
Université de Genève
A.E. Simon
Universität Bern
V. Singh
Istituto nazionale di astrofisica (INAF)
Alexis M. S. Smith
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
M. Sordet
Université de Genève
S.G. Sousa
Universidade do Porto
Manfred B. Steller
Institut fur Weltraumforschung
G.M. Szabó
Eötvös Loránd University (ELTE)
Nicolas Thomas
Universität Bern
M. Tschentscher
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
S. Udry
Université de Genève
V. Viotto
Istituto nazionale di astrofisica (INAF)
I. Walter
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
N. A. Walton
University of Cambridge
F. Wildi
Université de Genève
D. Wolter
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 643 202038677Ämneskategorier
Astronomi, astrofysik och kosmologi
Atom- och molekylfysik och optik
Annan fysik
Fundament
Grundläggande vetenskaper
DOI
10.1051/0004-6361/202038677