Kepler's Music of the Spheres Exhibit Wiki Home Page
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This is the wiki for the Music of the Spheres project.
What is a museum exhibit? It's more than just a static repository for the wisdom of past ages ... it is that and more - it engages the viewer and shows the synthesis of new knowledge and experience by illustrating old concepts and displaying them in a new way. How did our ancestors come upon their insights? How have great ideas been discovered?- Imagine that you are sitting on the sun. Planets do not orbit you
circularly; they do so elliptically. Their distance to you (the sun) is
not constant - there is a closest point (perihelion) and a farthest
(aphelion). As each planet moves towards and away from the perihelion
in its orbit, velocity increases and is represented, in the imagination
of Kepler, by changes in tone and pitch.
These observations made by Johannes Kepler (1571-1630) are pivotal to
our present-day understanding of the solar system. Kepler dreamed that
the planets' movements were of a divine order and that they
collectively formed the music of the spheres. He wrote, "the movements
of the heavens are nothing except a certain everlasting polyphony." As
you listen from the sun, focus on the warbling pitch of the
planets--the higher the pitch is, the faster is the planet's angular
velocity.
Kepler's greatest achievement was the formulation of the Laws of
Planetary Motion which made a fundamental break with astronomical
tradition in describing the orbits of the planets as elliptical rather
than circular and in recognising that a planet's speed is not uniform
but varies at different stages of its orbit. The first two Laws were
announced in 1609 in Astronomia Nova ('the new astronomy'). It took a
further nine years to formulate the Third Law which established a
relationship between a planet's distance from the Sun and the time it
takes to complete an orbit. This was announced in Harmonice Mundi
('harmony of the world'), published 1618. Collectively Kepler's Laws
superseded the ancient Ptolemaic concept of a spherical universe with
epicyclic motion. They provided the foundation upon which Isaac Newton
was to build his epoch-making theory of universal gravitation towards
the end of the 17th century.
- It was not possible until recently to accurately and easily reproduce the sounds specified by the orbits of the planets. Now Kepler's insights are more available to us all. On April 17, 2003, mathematicians and visual musicians Ralph Abraham and Pablo Viotti presented Kepler's music at the San Francisco Art Institute. Their performance is reproduced here in a way that allows you not only to hear the music of the spheres from the sun, which is not really the best place in the solar system for humans to listen, but from *any* planet. We think Jupiter is the best seat in the house, but what do we know. Take the two minute tour and be treated to the music of the spheres as heard from around the solar system, comparing those sounds to the speakers placed in the room around you.
- http://www.visual-kepler.org/ http://www.viotti.com/kepler.html
