The Space Studies Institute is a nonprofit research group founded by Gerard K. O'Neill, among the interests of which have been mass-drivers, lunar mining processes and simulants, composites from lunar materials, and solar power satellites. Its presidency was taken over by Freeman Dyson after O'Neill's death in 1992. SSI publishes a bimonthly newsletter, SSI Update, describing work-in-progress, and runs the biennial Princeton Conference on Space Manufacturing. Princeton, New Jersey.