γ-Ray astronomy is a valuable source of information on solar activity, supernovae and nucleosynthesis. Cosmic y-ray lines were first observed from solar flares and more recently from the galactic centre and a transient event. The latter may give an important insight into nuclear reactions taking Place near neutron stars and black holes and a measure of the gravitational redshifts of such objects.
- R. Ramaty
- R. E. Lingenfelter
