Two virtually identical passive satellites of the French Centre National d’Études Spatial (CNES) to assist geodetic (see geodesy) and geophysical studies. Each satellite is covered with sixty laser retroreflectors. The satellites were launched on 26 September 1993, from Kourou, French Guiana, Starlette into a near-circular orbit at an altitude of 812 km, and Stella into a polar orbit at a mean altitude of 800 km.