## Newtonian mechanics

According to classical mechanics, between two or more masses (or other forms of energy–momentum) a gravitational potential energy exists. Conservation of energy requires that this gravitational field energy is always negative.^{[2]}

Particularly, between any two point masses and (this works for the spherical bodies also), there always exists a gravitational force of where r is the distance between their centers. Increasing the distance from to reduces the force, but, since forces in Newton mechanics indicate how much potential energy is lost over space, , this separation requires of energy. Performing positive work equal to E units of energy, we can recede objects from *r*_{0} to *r*_{1} special units apart. By performing positive work equal to , the second term vanishes and objects are infinitely separated (). Because gravitational force stops pulling objects together at that distance, is known as gravitational binding energy, which is infinite at since the gravitational force is infinite there^{[citation needed]}.