Newton's law of universal gravitation

Newton's law of universal gravitation describes gravity as a force by stating that every particle attracts every other particle in the universe with a force that is proportional to their masses and inversely proportional to the square of the distance between their centers of mass. Separated, spherically symmetrical objects attract and are attracted as if all their mass were concentrated at their centers.

Source: Wikipedia — Newton's law of universal gravitation (CC BY-SA 4.0)