Newton's Principia

It was Isaac Newton's Principia that founded the law of universal gravitation on 5th July 1687. It is the same principia that inspired Albert Einstein into formulating the Einstein field equations (the general relativity theory). It is still the same principia, I believe, will lead us to the quantum theory of gravity (Quantum gravity) According to Newton's Principia, the force of gravity governs the movement of bodies in the solar system. It is this simple mathematical law which determines the motion of bodies. The force of gravity accurately predicts the planetary orbits, it was used to put the first man on the moon, it predicts the return of comets, the rotation of galaxies, the solar eclipses, artificial satellites, satellite communications and television, the GPS and interplanetary probes. I almost forgot, it is why NASA was established in the first place.