Ah! What an evocative thread! For fans of 2001 (and I include myself in their number) the music of Richard and Johann Strauss springs to mind and there is a suggestion of the celestial clockwork in their respective compositions used in the film. Gustav Holst wrote the famous "Planets Suite" with compositions dedicated to the individual planets (or rather the Greek gods from whom they were named) which is also an evocative piece of music and well worthy of the mantle of "Astronomy music."
My personal favorites however come from the little known genre of "Space Rock" (I Kid you not) and is exemplified by such bands as Gong, Neu, Kraftwerk, Tangerine Dream (Don't start, KM.) and my personal favorites, Hawkwind.
The first record that I ever owned was an old 78 rpm The Purple People Eater by Sheb Wooley and the first record that I ever bought with my own money was a 45 rpm single The Martian Hop by the Randells, so I was always going to be trouble when it came to music.
