I asked 'Pavement' fest founder Joel Peterson about the special relationship between Detroit and Sun Ra and the Arkestra and he had a great, thoughtful reply: "I think it can really be said that as much as the Arkestra ever had a mass audience, it can really be attributed to Detroit. Of course this is a very relative statement. But they certainly crossed over with the baby boomer generation more here than anywhere else. The multiple residencies, the association with John Sinclair and the MC5 — that stuff raised their profile with the rock generation not only regionally but nationally. When I presented the full Arkestra at Bohemian National Home, Danny Ray Thompson told me about their first show in Detroit. It was them, Howling Wolf, and James Brown! Could you imagine a bill like that?"
Ra was a really serious philosopher, theorist, and in his own way a very strong voice for black power. Too many people at the time dismissed him as a spacey freak who claimed to be from outer space (as if that were in any way a bad thing). I strongly recommend John Szwed's biography of Sun Ra for a taste of this.
In a discussion of Ra's discography and legacy at the great webzine Perfect Sound Forever, Kris Needs writes in a review of a set of live recordings from the early 1970s at the John Sinclair-prodiced Ann Arbor Blues Festival that "Sun Ra enjoyed a special relationship with Detroit after playing there with the MC5 in June, 1967 at the Community Arts Auditorium on Wayne State University. When they returned in May-June 1969 to play the Detroit Rock and Roll Revival with Chuck Berry, the MC5 and Stooges at the invitation of Five manager John Sinclair, they stayed next door to the large Victorian house occupied by the band and White Panther party members. The MC5 were major fans, having used Ra's "There" poem as launch-pad for their own "Starship" on Kick Out The Jams. In September 1972, the (Solar-Myth) Arkestra were invited back by Sinclair to play opening night of the Ann Arbor Blues and Jazz Festival in front of 12,000 punters, their biggest U.S. crowd yet. They turned the place out, flitting between space chants, squalling chaos and Ra's synth assaults. The date led to further dates around the world and return appearances at the next two Ann Arbor festivals. Sinclair licensed tapes of these performances to Alive/Total Energy, including 1972's Life Is Splendid, 1973's Outer Spaceways Employment Agency and 1974's It Is Forbidden, all three contributing to Art Yard's stupendous Wake Up Angels: Live At The Ann Arbor Blues & Jazz Festival 1972-73-74; which cataclysmically chronicles Ra's triumphs in the home of high-energy rock 'n' roll."
Sun Ra, a.k.a. Herman Poole "Sonny" Blount passed away in 1993 at the age of 79, but the music is still out there.