https://doi.org/10.1051/epjconf/20134703005
CHEOPS: A transit photometry mission for ESA's small mission programme
1 Center for Space and Habitability, University of Bern
2 Space Research and Planetary Science Division, Physikalisches Institut, Universität Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
3 Observatory of the University of Geneva
4 Space Research Institute, Austrian Academy of Sciences, Graz, Austria
5 Aix Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, 13388 Marseille, France
6 Université de Liége, Allée du 6 août 17, Sart Tilman, Liége 1, Belgium
7 Swiss Space Center, école Polytechnique Fédéral de Lausanne, Lausanne, Switzerland
8 Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden
9 Institute of Astronomy ETH Zürich
10 Department of Astronomy, Stockholm University, 106 91 Stockholm, Sweden
11 INAF Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy
12 Dipartimento di Fisica e Astronomia “Galileo Galilei”, Universita‘ di Padova, v.co dell'Osservatorio 3, 35122 Padova, Italy
13 Astrophysics Research Centre, School of Mathematics & Physics, Queen's University, University Road, Belfast BT7 1NN, UK
14 Osservatorio Astronomico di Padova, INAF, vicolo dell'Osservatorio 5, 35122 Padova, Italy
15 Centre Spatial de Liége
a e-mail: broeg@space.unibe.ch
Ground based radial velocity (RV) searches continue to discover exoplanets below Neptune mass down to Earth mass. Furthermore, ground based transit searches now reach milli-mag photometric precision and can discover Neptune size planets around bright stars. These searches will find exoplanets around bright stars anywhere on the sky, their discoveries representing prime science targets for further study due to the proximity and brightness of their host stars. A mission for transit follow-up measurements of these prime targets is currently lacking. The first ESA S-class mission CHEOPS (CHaracterizing ExoPlanet Satellite) will fill this gap. It will perform ultra-high precision photometric monitoring of selected bright target stars almost anywhere on the sky with sufficient precision to detect Earth sized transits. It will be able to detect transits of RV-planets by photometric monitoring if the geometric configuration results in a transit. For Hot Neptunes discovered from the ground, CHEOPS will be able to improve the transit light curve so that the radius can be determined precisely. Because of the host stars' brightness, high precision RV measurements will be possible for all targets. All planets observed in transit by CHEOPS will be validated and their masses will be known. This will provide valuable data for constraining the mass-radius relation of exoplanets, especially in the Neptune-mass regime. During the planned 3.5 year mission, about 500 targets will be observed. There will be 20% of open time available for the community to develop new science programmes.
© Owned by the authors, published by EDP Sciences, 2013
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
