The gravitational attraction between any two objects is given by the equation which symbolically summarizes Newton’s universal law of gravitation:
Fgravity = G M1 M2 / R2
where
Fgravity is the gravitational force between two objects,
M1 and M2 are the masses of the two objects, and
R is separation of their mass centers.
G is a constant number known as the universal gravitational constant.