Imperial Earth is the fascinating odyssey of Duncan Makenzie, traveling from Titan, a moon of Saturn, to Earth, as a diplomatic guest of the United States for the celebration of its Quincentennial in the year 2276. Titan, an independent republic, was originally colonized from Earth three generations earlier. Duncan's initial challenge is to prepare, physically and intellectually, for the 500-million-mile trip to Earth. Once there, he is caught up in a sweep of new experiences,…