The two volumes of Heliocentric Worlds (not the third volume which is only session recordings) were the recordings which established Sun Ra as a force to be reckoned with within free jazz. Volume One is a very loud album, the brass is quite atonal at times and the drums often join in the cacophony (some passages remind me of Hermann Nitsch at his most aggressive). I really enjoy the few moments where the electric piano is being stabbed to death on Other Worlds or Cosmos for example. The latter is a great number: starting off with weird string arrangements, the drums, horns and electric piano then take turns playing the lead role in the (controlled) mayhem which ensues. Absolutely stunning! Nebulae furthers Ra's constant obsession with space; it is an offbeat number for solo electric piano (it sounds like the theme song to M. Roger's Neighborhood on acid). Classic all the way.