Update: I just read your consideration of asteroids. Brings to mind, which objects are appropriate due to their size? About your question concerning moons: Yes, they do not orbit the Sun per se, but piggy back with their host planets. Thus, would it be appropriate to include their tones as an amplitude modulation of their host planet's frequency? E.g., Our Moon's period superimposed on Earth's 265 day period? Alternate Music marylandgreenpower 2009-10-15 14:46:29 2009-10-15 14:40:25 5 This piece is incredibly interesting... To use the orbits of the planets and convert that into pitches for use in music... Very cool. I am very glad the author has decided to include the frequencies (Hz) of each planet. I have entered these frequencies into my tunesmithing software (Scala) and have been improvising over this ambient work. It's something a lot more people should try - I'm thinking about composing some music with this planetary tuning myself. (Though I omitted Pluto). You SHOULD listen to this if you want to hear something very different. :) New harmonies Sevish 2010-07-08 13:54:58 2010-07-08 13:54:58 4 2 4.50