F = G (m1*m2)/r²

Where:

F is the attractive gravitational force between two bodies.

m1 and m2 represent the masses of the two bodies.

r is the separation between the centers of mass of the two bodies.

G is Newton's gravitational constant, where G = 6.67x10^-11 (N*m²)/kg² (Newtons)*(meters squared) over (kilograms squared).