Star Surgeon ( 1960) interestingly posits an Earth which, while being the main medical centre of all the inhabited worlds, is still in the position of having to apply to join the Galactic Confederation. In Rocket to Limbo (October Satellite exp 1957), mankind's destiny is explained by aliens in the course of a quest for a long-lost Starship. The first of these, Trouble on Titan ( 1954), features rebellion and conflict within a Space-Opera solar system, as do others like Raiders from the Rings ( 1962), where conflict between an oppressive Earth regime and Libertarian Spacers is finally halted by the intervention of superior, peaceful Aliens. He began publishing sf with "High Threshold" for Astounding in March 1951, assembled with other material as The Universe Between (March, September 1951 Astounding fixup 1965), though his initial reputation was as a reliable creator of Young Adult novels. (1928-1992) US author and physician much of his nonfiction was in the field of popular Medicine – Intern ( 1965) as by "Doctor X" being a great success.