Changes

* Kepler presented his first two laws of planetary motion in 1609 by using the notes of his predecessor ''TYCHO BRAHE'' and third law in 1619.

* Kepler presented his first two laws of planetary motion in 1609 by using the notes of his predecessor ''TYCHO BRAHE'' and third law in 1619.

* Kepler developed his laws empirically from observation, as opposed to deriving them from some fundamental theoretical principles. About 30 years after Kepler died, Isaac Newton was able to derive Kepler's Laws from basic laws of gravity.

* Kepler developed his laws empirically from observation, as opposed to deriving them from some fundamental theoretical principles. About 30 years after Kepler died, ''Isaac Newton'' was able to derive ''Kepler's Laws'' from ''basic laws of gravity''.

* Newton presented his law of universal gravitation as a case study of his laws of motion. All matter exerts a force, which he called gravity, that pulls all other matter towards its center. The strength of the force depends on the mass of the object: the Sun has more gravity than Earth, which in turn has more gravity than an apple. Also, the force weakens with distance. Objects far from the Sun won’t be influenced by its gravity.

* Newton presented his law of universal gravitation as a case study of his laws of motion. All matter exerts a force, which he called gravity, that pulls all other matter towards its center. The strength of the force depends on the mass of the object: the Sun has more gravity than Earth, which in turn has more gravity than an apple. Also, the force weakens with distance. Objects far from the Sun won’t be influenced by its gravity.