It is the energy possessed by a body due to the interaction forces inside the body . This can be defined as the work done by external agent in assembling all the particles of a body in a definite shape and size or it is the work done in creating a body.
– gravitational self energy of a hollow sphere of mass M and radius R is given as
Uself = – GM²/2R
– gravitational self energy of the solid sphere of mass M and radius R is given as
Uself = – 3GM²/5R