This is the second edition of the first book published by astronomer Johannes Kepler when he was 25 years old, in which he insisted that he clarify the secrets of the solar system. Kepler accepted heliocentrism by Copernicus; and stated that the relative size of planetary orbit was determined by inscribing and circumscribing five regular polyhedrons. Copperplate prints produced by etching represent a model of the trajectory that Kepler envisioned. As a result of sending his publications to astronomers around the country, Kepler was assigned as an assistant under Tycho Brahe. Kepler took over Tycho's vast and accurate observational data, and he established the three laws of planetary motion.