Harmonices

His works Astronomia nova and Harmonices Mundi were further codified by later astronomers.

Quotation from Caspar, Kepler, pp. 265–266, translated from Harmonices Mundi In Harmony, he attempted to explain the proportions of the natural world—particularly the astronomical and astrological aspects—in terms of music.

The result, published in 1619, was Harmonices Mundi ("Harmony of the World").