You can often find "borrowable" or public domain versions of Donahue’s translation here.
Kepler used the precise observational data of Tycho Brahe to formulate the first two of his three famous laws of planetary motion within this text: "Kepler: 'Astronomia Nova' ('New Astronomy')" - eCommons astronomia nova pdf
also offers a "Selections" volume focusing on the core physical arguments. Internet Archive Key Scientific Breakthroughs You can often find "borrowable" or public domain
Kepler proved planets move in elliptical orbits with the Sun at one focus, not in circles . not in circles .