Welcome to the new New Astronomy webpage! This is the second edition of a pedagogical work-through of Johannes Kepler’s great book, Astronomia Nova, a work of unexaggerably great importance for mankind. Kepler created modern science with this work, which breaks from the view that the complete perfection of the heavens have nothing to do with the physical causes that operate down here in the earthly domain. His book, subtitled Astronomy Based on Causes departs the mathematical world of previous astronomers, and creates the new field of astrophysics.

This page currently (Jan 2013) treats Part I of Kepler’s work, in which he demonstrates that the geometrical differences between the planetary hypotheses of Ptolemy (who says the Earth doesn’t move), Copernicus (who says that it does), and Tycho Brahe (the expert observation-maker) are all different ways of looking at the same thing. To come to a real answer of what happens in the heavens, Kepler will make a physical hypothesis about the role of the Sun causing the motion of the planets.

Although this site is still in progress, the old site, which covers the entire book, is available.


Next: Introduction