On the Revolutions of the Heavenly Spheres

About this book

Why should the earth move at all? How can we know the order and the distances of the planets? Why do Mars, Jupiter and Saturn sometimes seem to go backwards? Copernicus answers step by step, with his own observations from Frauenburg and the observations of Ptolemy, Hipparchus and al-Battani — and in the famous diagram of Book One the sun sits at the center, "as if seated on a royal throne".

Rendered into modern English by BlusaBooks with the help of AI tools, working from images of the pages of the 1543 Nuremberg first edition. Every sentence, not a selection or a summary: all six books, Osiander's anonymous preface, Cardinal Schönberg's letter and the dedication to Pope Paul III. The ideas of the age (orbs, eccentrics, epicycles) are kept as Copernicus wrote them; the notes explain them.

What is inside

• the title page of 1543 and the famous diagram of the sun at the center of the world
• Book One: the new system of the world and the trigonometry behind it, with the table of chords
• Book Two: the sphere, sunrise and sunset, and the star catalogue of more than 1,000 stars (transcribed and translated)
• Book Three: the precession of the equinoxes and the solar year · Book Four: the moon and eclipses
• Books Five and Six: the five planets in longitude and latitude
• all 145 original diagrams and 68 original table pages from the 1543 edition, each table with a translated title
• 329 short footnotes on the same page: who each person was, what the old terms mean, what we know today
• the 1543 errata page as an appendix
• colour illustrations: Copernicus in Frauenburg, the manuscript at the printing house, the first printed copy (illustrations created with AI tools)
• a foreword on Copernicus, Rheticus, the hidden preface and the ban of 1616; commentary at the end for each book: in plain words, what Copernicus shows, what we know today

Who it is for

Readers of the history of science and astronomy, students and teachers, lovers of classic and banned books, anyone curious about how we learned that the earth moves. A thoughtful gift for a lover of science and old books.

A historical source: Copernicus still used circles, eccentrics and epicycles; Kepler later showed that the orbits are ellipses. The notes and commentary explain what we know today.