In
classical mechanics, the
gravitational potential at a location is equal to the
work (
energy transferred) per unit mass that would be done by the force of
gravity if an object were moved from its location in space to a fixed reference location. It is
analogous to the
electric potential with
mass playing the role of
charge. The reference location, where the potential is zero, is by convention
infinitely far away from any mass, resulting in a negative potential at any distance.