The Centre de recherches en géodynamique et astrométrie (CERGA) was a scientific department of the Observatoire de la Côte d'Azur (OCA). It included 28 researchers and as many engineers and technicians located on the Observatory sites of Nice, Grasse and Calern (Caussols). The scientific activities covered fields as diverse as fundamental astronomy, celestial mechanics, and space geodesy. CERGA was in charge of several observing facilities of the Lunar Laser Ranging experiment, for example, the lunar-laser ranging telescope and the two satellite laser stations.