COROT mission is managed by CNES (French National Space Agency) in association with three major French laboratories (LAM, LESIA, IAS) and several European countries, contributing to the payload and the ground segment.
This astronomy mission objectives are astero-seismology as well as planet finding.
The COROT spacecraft is based on a PROTEUS low Earth orbit recurrent platform, developed by CNES and Alcatel Alenia Space. It was injected on 27th December 2006 at a 898 km polar and circular orbit by a Soyuz launcher and is being operated from CNES-Toulouse.
This paper focuses on the thermal control design and first in-orbit performances of the payload which mainly consists in an afocal telescope, a wide field camera with cooled CCDs, and an equipment bay.
Largely using standard and well-proven technologies, this paper also points out some thermal control specificities and techniques used.
Quite different temperatures levels lead to optimise insulation between thermal enclosures further described in the paper.
Main difficulty solved was to respect main scientific performances translated into engineering thermal requirements such as:
-
high orbital and “150 days” telescope stability (typically few tenths of a °C, and 1°C)
-
cold and highly stable focal plane in quite disadvantageous orbital conditions such as 3-axes inertial pointing in LEO (typically −40°C with 30 m K stability)
-
high orbital electronics stability (typically 0.3°C).