Definitions list
  • Kepler's laws
    Three natural laws describing the motions of the planets in the Solar System, derived by the German astronomer Johannes Kepler between 1602 and 1618. The laws cover the shape and dimensions of orbits, and velocity of motions. They also apply to spacecraft.
  • keplerian orbit
    Orbit described by a celestial body about another under the sole action of mutual gravitational attraction. A real orbit is hardly ever Keplerian due to perturbations. Named after German astronomer Johannes Kepler, who established the 3 laws of planetary motion. Synonym: unperturbed orbit.
    What is an orbit?
  • Kuiper belt
    Vast region of the Solar System populated by asteroids and comets, extending in the ecliptic plane beyond the orbit of Neptune.