Cheops: An exoplanet follow-up mission
Cheops, the CHaracterising ExOPlanet Satellite, is ESA’s first mission dedicated to the study of extrasolar planets, or exoplanets. It will observe bright stars that are already known to host planets, measuring minuscule brightness changes due to the planet’s transit across the star’s disc.
Unlike previous exoplanet satellites, such as the CNES-led CoRoT (Convection, Rotation and planetary Transits) or NASA’s Kepler and Tess missions, Cheops is not a ‘discovery machine’ but rather a follow-up mission, focusing on individual stars that are already known to host one or more planets. The exquisite precision with which Cheops is able to measure planetary transits, together with the stability of the telescope, will enable astronomers to determine planet sizes both accurately and precisely.
