1. PERSONNEL During the reporting year the research staff consisted of Neta Bahcall, Renyue Cen, Bruce

During the reporting year the research staff consisted of Neta Bahcall, Renyue Cen, Bruce Draine, Edward Fitzpatrick, Jeremy Goodman, J. Richard Gott, James Gunn, Edward Jenkins, Gillian Knapp, Russell Kulsrud, Jeremiah Ostriker, Bohdan Paczyński, David Spergel, Michael Strauss, Scott Tremaine and Edwin Turner, as well as postdoctoral fellows Greg Bryan, Alex Lazarian, Željko Ivezić, Todd Tripp, Michael Vogeley, and Yun Wang. Christophe Alard (Cambridge) and Janusz Kaluzny (Warsaw University Observatory) held visiting research appointments during summer and fall 1997. Edward Fitzpatrick left in summer 1997 to take up a faculty position at Villanova University, and Michael Richmond left in summer 1997 to begin a faculty position at the Rochester Institute of Technology. Tatsushi Suginohara returned to the University of Tokyo in March 1998. Turner was on research leave during the fall term, and Goodman and Paczyński were on leave during the spring.