How far can the profession of bioethics take you? Possibly into outer space, it seems. NASA has recently engaged its first chief bioethicist, Paul Root Wolpe, of the University of Pennsylvania, to help it think through knotty ethical issues about space flight. Currently he is working on policies for long flights to Mars and the moon, which could begin by 2020. He deals with such problems as how to deal with a psychotic crew member who attacks his comrades or the amount of radiation to which astronauts can be safely exposed.