An '''orbit''' is an object's rotation around another. Orbits are caused by the [[gravity]] of a large mass attracting a smaller mass. The smaller mass is prevented from falling into the large mass by a large [[velocity]] perpendicular to the object it is orbiting around. The concept of orbiting in the solar system has changed drastically over time. [[Scientists]] assumed that the orbits of [[planet]]s observable in [[Kepler]]'s times were circular. Kepler was the first to propose that the planets' orbits were elliptical, thus improving the accuracy and prediction-value of the heliocentric view of the solar system. [[Comet]]s, on the other hand, have highly [[eccentric]] orbits with only one [[focal point]] inside the [[Sun]]. | An '''orbit''' is an object's rotation around another. Orbits are caused by the [[gravity]] of a large mass attracting a smaller mass. The smaller mass is prevented from falling into the large mass by a large [[velocity]] perpendicular to the object it is orbiting around. The concept of orbiting in the solar system has changed drastically over time. [[Scientists]] assumed that the orbits of [[planet]]s observable in [[Kepler]]'s times were circular. Kepler was the first to propose that the planets' orbits were elliptical, thus improving the accuracy and prediction-value of the heliocentric view of the solar system. [[Comet]]s, on the other hand, have highly [[eccentric]] orbits with only one [[focal point]] inside the [[Sun]]. |