| |
ScienceDaily: Astronomy (Site not responding. Last check: 2007-10-25) |
 | | Later, with the work of astronomers Kepler and Newton, whose work led to the development of celestial mechanics, the mathematical prediction of the motions of celestial bodies interacting gravitationally became the focus of astronomy. |
 | | Kepler was the first to devise a system that described correctly the details of the motion of the planets with the Sun at the center. |
 | | However, Kepler did not succeed in formulating a theory behind the laws he wrote down, and parts of his discoveries are no longer considered significant, e.g., the spacing of planetary orbits to allow insertion of regular solids between adjacent planets' spheres. |
| www.sciencedaily.com /encyclopedia/astronomy (3214 words) |