SPACE RESOURCES and SPACE SETTLEMENTS Technical papers derived from the 1977 Summer Study at NASA Ames Research Center, Moffett Field, California Study Director Gerard K. O'Neill Princeton University, Princeton, New Jersey Editors John Billingham and William Gilbreath NASA Ames Research Center, Moffett Field, California Brian O'Leary Princeton University, Princeton, New Jersey Manuscript Editor Beulah Gossett Los Altos, California NI\S/\ National Aeronautics and Space Administration Scientific and Technical Information Branch Washington, D.C. 1979 NASA SP-428