Nova Ophiuchi of 1604 as a Supernova.

Nova Ophiuchi of 1604 is one of the earliest well-observed novae. Its position has recently been rede- termined by Schlier and Boehme from the original measures of FabriciUs and Kepler. The light-curve, derived in the present paper, shows that the star was a supernova of type I, which at maximum reached the apparent magnitude -2.2. A check of the Chinese version of the apparition against the light-curve shows that the Chinese reports about new stars were based on careful observations. A search for the remnant of the supernova led to the discovery of a small patch of emission nebulosity, which is undoubtedly a part of the masses ejected during the outburst. The investigation of this remnant meets with unusual difficulties because the supernova is behind heavy obscuration. The determination of the distance and the luminosity of the supernova must therefore be left to future observations