Character Catalog

Kepler's first published work, defending Copernicus's heliocentric system. Although his geometric model (Platonic solids) proved incorrect, the work reveals his lifelong quest for a universal mathematical order.

A landmark work stating the first two laws of planetary motion: orbits are elliptical, and planets sweep out equal areas in equal times. A decisive break with the long tradition of perfect circular orbits.

A treatise on optics in which Kepler provides a theoretical explanation of how lenses work and proposes a new telescope design using two convex lenses, known as the 'Keplerian astronomical telescope'.

A major work blending astronomy, geometry, and music, in which Kepler states his third law: the square of a planet's orbital period is proportional to the cube of the semi-major axis of its orbit.

A seven-volume astronomy textbook synthesizing all of Kepler's discoveries. This accessible educational work spread his laws among European scholars, though the Church placed it on the Index in 1619.

Tables of planetary positions based on Brahe's observational data and Kepler's laws. Dedicated to Emperor Rudolf II, they enabled predictions of planetary positions with unprecedented accuracy and remained in use for a century.

An imaginary voyage to the Moon, considered one of the earliest works of science fiction. Kepler describes Earth as seen from the Moon and uses fiction as a vehicle to spread his Copernican ideas.

I confess that when Tycho died, I took possession of his observations as an inheritance left for me, with the intention of interpreting them... The orbits of the planets are ellipses with the Sun at one of the foci.

The Earth is the measure of all planetary orbits. Circumscribe a dodecahedron around it; the sphere surrounding it will be that of Mars. Around Mars, circumscribe a tetrahedron; the sphere surrounding it will be that of Jupiter.

The square of the orbital periods of the planets is proportional to the cube of their mean distances from the Sun. I have gathered this treasury of astronomy from Pythagoras and Ptolemy, and purified it of errors.

I believe in Copernicus and not in those who laugh off this hypothesis. I must say that your telescope and your observations have removed all doubt from my mind about the motion of the Earth.

The Sun, source of light and heat, is the driving force of the planetary world. Its power spreads through space and diminishes with distance, carrying the planets along in their courses.

Kepler's birthplace, a small imperial city of the Holy Roman Empire. A statue and a museum there honor his memory today.

Tycho Brahe's observatory where the astronomical data that Kepler relied on throughout his life were collected. Although he never worked there himself, the place is inseparable from his work.

Capital of the Empire where Kepler lived from 1600 to 1612 as imperial mathematician at the court of Rudolf II. It was here that he wrote the Astronomia Nova and formulated his first two laws.

The city where Kepler resided from 1612 to 1626 as provincial mathematician. There he wrote the Harmonices Mundi and the Rudolphine Tables despite the upheavals of the Thirty Years' War.

The city where Kepler died in November 1630 while traveling to recover funds owed to him. His tomb, destroyed during the Thirty Years' War, was reconstructed in the 19th century.