First astrometric observations of space debris with the MéO telescope Original Research Article

The MéO (for Métrologie Optique) telescope is the Satellite and Lunar Laser Ranging (SLR) dedicated telescope of Observatoire de la Côte d’Azur (France) located at plateau de Calern. The telescope uses an altazimuth mount. The motorization of the mount has a capability of 6 deg/s allowing the follow up of Low Earth Orbits (LEO) satellites, as well as Medium Earth Orbits (MEO) and geostationary (GEO) satellites, and the Moon. The telescope has a primary mirror of 1.54 m. It uses a Nasmyth focus equipped with an EMCCD camera. The telescope field of view, defined by the equivalent focal length and the size of the camera, is currently 3.4 arcmin × 3.4 arcmin.Space debris observation with an optical telescope ideally requires a large field of view, accurate pointing, a fast slew rate, a high sensitivity, accurate astrometric positions, and a precise method for orbit propagation. The challenge is to obtain accurate orbits for all debris without compromising the field of view. The MéO telescope has a larger diameter than the ones habitually used for space debris tracking. It should improve the current accuracy of observations in the GEO region. For LEO, such sensitivity should allow observations of small pieces of debris at low altitudes.