In the summer and autumn of 2006 I read several interviews with Brian May in which he mentioned his desire to complete the PhD that he had abandoned in 1974. I looked up the papers he had published while a PhD student, which were on spectroscopic studies of the motion of the dust responsible for the zodiacal light, and felt that there was a basis for a thesis. Since he had been a student at Imperial, I knew, as Head of the Astrophysics Group at Imperial,...