The CoRoT satellite in flight: description and performance^*

¹ Observatoire de Paris, UMR 8109, 5 place J. Janssen, 92195 Meudon, France
² Centre National d'Études Spatiales, 18 avenue E. Belin, Toulouse, France
³ Laboratoire d'Astrophysique de Marseille, Traverse du Siphon, 13376 Marseille Cedex 12, France
⁴ Centre Spatial de Liége, ULG Science Park, Av. du Pré-Aly 4031 Angleur-Liége, Belgium
⁵ Institute of Planetary Research, DLR, Rutherfordstr. 2, 12489 Berlin, Germany
⁶ Space Research Institute, Austrian Academy of Science, Schmiedlstrasse 6, 8042 Graz, Austria
⁷ Institut d'Astrophysique Spatiale, Université Paris XI, 91405 Orsay, France
⁸ European Space Agency, ESTEC, SCI-A, PO Box 299, 2200AG, Noordwijk, The Netherlands
⁹ Observatoire Midi-Pyrénées, 14 Av. E. Belin, Toulouse, France
¹⁰ Instituut voor Sterrenkunde, Departement Natuurkunde en Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, Office 03.31, 3001 Leuven, Belgium 

¹¹ CLIPhIT, Arnfriedstrasse 17, 12683 Berlin, Germany
¹² Technologiepark 1, 15236 Frankfurt/Oder, Germany

Received: 26 August 2008
Accepted: 13 January 2009

Abstract

Context. CoRoT is a space telescope dedicated to stellar seismology and the search for extrasolar planets. The mission is led by the CNES in association with French laboratories and has a large international participation. The European Space Agency (ESA), Austria, Belgium, and Germany contribute to the payload, and Spain and Brazil contribute to the ground segment. Development of the spacecraft, which is based on a PROTEUS low earth orbit (LEO) recurrent platform, commenced in October 2000, and the satellite was launched on December 27, 2006.

Aims. The instrument and platform characteristics prior to launch have been described in ESA publication (SP-1306). In the present paper we explain the behaviour in flight, based on raw and corrected data.

Methods. Five runs have been completed since January 2007. The data used here are essentially those acquired during the commissioning phase and from a long run that lasted 146 days. These enable us to give a complete overview of the instrument and platform behaviour for all environmental conditions. The ground based data processing is not described in detail because the most important method has been published elsewhere.

Results. We show that the performance specifications are easily satisfied when the environmental conditions are favourable. Most of the perturbations, hence data corrections, are related to LEO perturbations: high energy particles inside the South Atlantic Anomaly (SAA), eclipses and temperature variations, and line of sight fluctuations due to the attitude control system. Straylight due to the reflected light from the earth, which is controlled by the telescope and baffle design, appears to be negligible.