The relationship between orbits and gravity is the force that governs and sustains orbital motion. In Newtonian physics, an orbit arises when the gravitational attraction between a central massive body and a less massive object provides the centripetal force necessary to continuously curve the object's path into a closed trajectory rather than allowing it to move in a straight line or fall directly inward.
An object in orbit possesses sufficient tangential velocity such that, as it falls toward the central body under gravity, its forward motion carries it around the curve of the central body's gravitational field, perpetually missing the surface and tracing a repeating path. For circular orbits, the gravitational force equals the required centripetal forces, leading to the orbital speed, where the gravitational constant, is the central mass, the orbiting mass, and is the orbital radius. This balance explains phenomena like satellites around Earth or planets around the Sun.
Kepler's laws of planetary motion describe the motion and behavior of planets and other celestial bodies in the solar system. Kepler's laws have played a crucial role in shaping our knowledge of celestial mechanics and continue to be relevant in modern astronomical research and space exploration. It describe the orbits, planets move in ellipses with the Sun at one focus.
