| Acknowledgements This document was written by the GRAPWG committee members in consultation with many colleagues in the astronomy and physics communities. Significant assistance in production and editing was provided by D. Macomb (GSFC). Valuable input was given by R. Harnden, L. Kaluzienski (NASA HQ), and R. Ramaty (GSFC). Editing and graphics assistance by K. Pollock, C. Shrader, T. Randall, M. Kiely and C. Ladd (GSFC) was gratefully received. |