Astrophysics with HESSI
  In the summer of the year 2000, a NASA Small Explorer satellite, the High Energy Solar Spectroscopic Imager (HESSI), will be launched. It will consist of nine large, coaxial germanium detectors viewing the Sun through a set of Rotation Modulation Collimators and will accomplish high-resolution imaging and spectroscopy of solar flares in the x-ray and gamma-ray bands. Here we describe some of the astrophysical observations HESSI will also perform in addition to its solar mission. 
D. M. Smith, R. P. Lin, J. McTiernan and A. S. Slassi-Sennou (Space   Sciences Laboratory, University of California, Berkeley)