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Physics News Update
Number 112 (Story #1), January 28, 1993 by Phillip F. Schewe and Ben Stein

THE FLUX OF COSMIC RAYS FROM THE SMALL MAGELLANIC CLOUD is smaller than one would expect if cosmic rays were extragalactic in origin. Measurements by the Gamma Ray Observatory of gamma rays (with energies greater than 100 MeV) resulting from the collision of cosmic-ray nucleons and electrons with interstellar matter recorded a flux of 0.5 x 10**-7 photons/sec-cm**2, one fifth the expected flux (P. Sreekumar et al., 11 Jan. 1993 Physical Review Letters). The GRO scientists conclude that cosmic rays are almost certainly galactic in origin; determining the nature of their source is another matter. (Nature, 21 Jan. 1993.)