Andromeda is a wideeld, imaging, hard X-ray/soft gamma-ray instrument capable of detecting gamma-ray bursts (GRBs) a factor 20 times fainter than GRO/BATSE. During 1-year of a two-year mission, it could determine whether GRBs are Galactic or cosmological in origin by searching for an excess of bursts towards the nearby Andromeda galaxy (M31). As a pointed, imaging instrument with sensitivity in...