Abstract: A spacecraft for geodetic applications designed to travel along a trajectory in an orbital plane around a planet, embodying at least one cube corner retroreflector designed to face the planet at least temporarily and having an apex, a normal, and three faces which are substantially orthogonal with respect to one another, to within an arcminute, forming three dihedral angles at substantially equal angular distances from this normal, the effective diameter of this cube corner being at least 3 centimeters, the apex being located, relative to the center of mass of the spacecraft, at a distance whose projection on an imaginary line joining the center of mass to the center of the planet remains at all times at a known value to within variations of less than 5 centimeters.