Low mass velocity-aberration correcting retroreflector geodetic satellite

A spacecraft for geodetic applications adapted to travel along a trajectory within an orbital plane about a planet, said spacecraft comprising:

• at least one cube corner retroreflector adapted to face, at least temporarily, said planet, said at least one cube corner retroreflector having an apex, a retroreflector normal axis, and three reflecting planar faces substantially orthogonal to one another and converging into three dihegral angles forming substantially equal angles with respect to said retroreflector normal axis;
• said at least one cube corner retroreflector further having an effective diameter of at least 3 centimeters;
• means for locating said apex of said at least one cube corner retroreflector at a predetermined distance relative to the center of mass of said spacecraft;
• and
• means for maintaining a projection of said predetermined distance on a line connecting the center of mass of said spacecraft to the center of mass of said planet at a length which remains when said at least one retroreflector faces said planet at less than .+-.5 centimeters from a predetermined value.