Fifteen hundred years from now, a man will be selected to go back in time to prevent a catastrophic event which turned his world into a dystopia. Sent back in time, he was enveloped in empyrean fire, the strands of energy that make up time itself.
Crash-landing near Astro City in late 1985, he learned how to master and channel the empyrean forces that had suffused his body -- finally learning to control his powers in time to prevent the destruction of the Space Shuttle Challenger, the event he had been sent to avert. He described himself to journalists as nothing more than "a Good Samaritan", and has continued to help his fellow man in Astro City ever since.
John JG Roshell has also been struggling with the empyrean challenge of fitting all of Kurt Busiek's Astro City dialogue into balloons with the regular Samaritan font, so he created the Samaritan Tall font to help his fellow comic book letterers! It's kinda the same thing really.