Celestial mechanics Celestial mechanics Celestial mechanics is the branch of astronomy that deals with the motions of objects in outer space. Historically, celestial mechanics applies principles of physics (classical mechanics) to astronomical objects, such as stars and planets, to produce ephemeris data. As an astronomical field of study, celestial mechanics includes the sub-fields of orbital mechanics, which deals with the launching and orbits artificial satellites, and lunar theory, a specialty which deals with the complications of the orbit of the Moon. Modern celestial mechanics tends to divide between five broad fields of study: All of the above fields overlap, but are sometimes
Dynamics of the celestial spheres associating an angel with each of the spheres. Moreover, Aquinas rejected the idea that celestial bodies are moved by an internal nature, similar to the heaviness and lightness that moves terrestrial bodies. Attributing souls to the spheres was theologically controversial, as that could make them animals. After the Condemnations of 1277, most philosophers came to reject the idea that the celestial spheres had souls. Robert Kilwardby (c. 1215–1279) discussed three alternative explanations of the motions of the celestial spheres, rejecting the views that celestial bodies are animated and are moved by their own spirits or souls, or that the celestial