<span>Johannes Kepler, an apprentice of Brahe, believed in the heliocentric universe but rejected past astronomers' belief in "Circular Orbit Path." The circular orbit path refers to the path the planets in the solar system is following. It is believed before that it follows a circular path rather than an elliptical one.</span>
Gravity is a force in which everything in the universe is trying to pull everyother thing towards themsef. Here, the sun's gravity keeps the planet in orbit.