55 Cancri e's occultation captured with CHEOPS

Author(s)
B. O. Demory, S. Sulis, E. Meier Valdés, L. Delrez, A. Brandeker, N. Billot, A. Fortier, S. Hoyer, S. G. Sousa, K. Heng, M. Lendl, A. Krenn, B. M. Morris, J. A. Patel, Y. Alibert, R. Alonso, G. Anglada, T. Bárczy, D. Barrado, S. C.C. Barros, W. Baumjohann, M. Beck, T. Beck, W. Benz, X. Bonfils, C. Broeg, M. Buder, J. Cabrera, S. Charnoz, A. Collier Cameron, H. Cottard, Sz Csizmadia, M. B. Davies, M. Deleuil, O. D.S. Demangeon, D. Ehrenreich, A. Erikson, L. Fossati, M. Fridlund, D. Gandolfi, M. Gillon, M. Güdel, K. G. Isaak, L. L. Kiss, J. Laskar, A. Lecavelier Des Etangs, C. Lovis, A. Luntzer, D. Magrin, L. Marafatto, P. F.L. Maxted, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, E. Pallé, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, F. Ratti, H. Rauer, I. Ribas, N. C. Santos, G. Scandariato, D. Ségransan, A. E. Simon, A. M.S. Smith, M. Steller, Gy M. Szabó, N. Thomas, S. Udry, V. Van Grootel, N. A. Walton
Abstract

Past occultation and phase-curve observations of the ultra-short period super-Earth 55 Cnc e obtained at visible and infrared wavelengths have been challenging to reconcile with a planetary reflection and emission model. In this study, we analyse a set of 41 occultations obtained over a two-year timespan with the CHEOPS satellite. We report the detection of 55 Cnc e's occultation with an average depth of 12 ± 3 ppm. We derive a corresponding 2Ïà  upper limit on the geometric albedo of Ag < 0.55 once decontaminated from the thermal emission measured by Spitzer at 4.5 μm. CHEOPSâà €à ™ s photometric performance enables, for the first time, the detection of individual occultations of this super-Earth in the visible and identifies short-timescale photometric corrugations likely induced by stellar granulation. We also find a clear 47.3-day sinusoidal pattern in the time-dependent occultation depths that we are unable to relate to stellar noise, nor instrumental systematics, but whose planetary origin could be tested with upcoming JWST occultation observations of this iconic super-Earth.

Organisation(s)
Department of Astrophysics
External organisation(s)
Universität Bern, Aix-Marseille Université, Université de Liège, Stockholm University, Université de Genève, Universidade do Porto, University of Warwick, Österreichische Akademie der Wissenschaften (ÖAW), Institute of Astrophysics of the Canary Islands, University of La Laguna, Spanish National Research Council (CSIC), Institute of Space Studies of Catalonia (IEEC), Admatis Ltd., European Space Astronomy Centre (ESA), University of Grenoble Alpes, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Université de Paris, University of St. Andrews, Almatech SA, Lund University, Leiden University, Chalmers University of Technology, Università degli Studi di Torino, Science and Operations Department - Science Division (SCI-SC), Eötvös Loránd Research Network, Eötvös Loránd University Budapest, Université de recherche Paris Sciences et Lettres, Université Paris VI - Pierre-et-Marie-Curie, Osservatorio Astronomico, Keele University, INAF-Osservatorio Astrofisico di Catania, University of Padova, Eidgenössische Technische Hochschule Zürich, University of Cambridge, Technische Universität Berlin, Freie Universität Berlin (FU)
Journal
Astronomy and Astrophysics
Volume
669
No. of pages
10
ISSN
0004-6361
DOI
https://doi.org/10.1051/0004-6361/202244894
Publication date
01-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics, 103038 Space exploration
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/8853d609-4e11-4f7d-b878-63bec1acb38a