The mutual attraction of all masses in the universe. Newton's Law of Universal Gravitation holds that every two bodies attract each other with a force that is directly proportional to the product of their masses, and inversely proportional to the square of the distance between them. This relation is given by the formula at right, where F is the force of attraction between the two objects, given G the Universal Constant of Gravitation, masses m1 and m2, and d distance. Also stated as Fg = gmm/r2 where Fg is the force of gravitational attraction, M the larger of the two masses, m the smaller mass, and r the radius of separation of the centres of the masses. See also weight.