Joe Johnstone wrote science fiction until he grew too old to hold a pen. He never did make it to space. He had to die to do that. In 2092, the line has blurred between the living and the dead. Between organic intelligence and manufactured. Humanity’s first interstellar ships soar into the cosmos for exploration and colonization, leaving a tired and battered Earth behind. They are crewed by artificial intelligences and ghosts like Joe. Will the mission of one such ship, the Excelsior, succeed?