space motion

"Space motion" refers to the movement of celestial bodies through space. This includes the motion of Earth and other solar system members as they travel with the Sun. It also encompasses the movement of stars, which can be described by their proper motion (across the line of sight) and radial velocity (along the line of sight).123

Kepler's laws of planetary motion describe how planets orbit the Sun in elliptical paths, sweeping out equal areas in equal times, and relating their orbital periods to their distances from the Sun. These laws were foundational for Isaac Newton's theory of gravitation. Celestial mechanics is the broader field that applies classical mechanics to the motion of celestial bodies, primarily considering gravitational forces but also other influences like radiation pressure and electromagnetic forces.456