science · 15 May 1618 · 406 years ago
In 1618, Johannes Kepler discovered his harmonics law published in his five-volume work Harmonices Mundi (Harmony of the Worlds, 1619). He attempted to explain proportions and geometry in planetary motions by relating them to musical scales and intervals (an extension of what Pythagoras had described as the “harmony of the spheres”.) Kepler said each planet produces musical tones during its revolution about the sun, and the pitch of the tones varies with the angular velocities of those planets as measured from the sun. The Earth sings Mi, Fa, Mi. At very rare intervals all planets would sing in perfect concord. Kepler proposed that this may have happened only once in history, perhaps at the time of creation.
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