| Abstract | Observations in the 21-cm line of neutral hydrogen have revealed the existence of a companion of the large Scd galaxy IC 342, about 94 arc min to the South-East. The difference in systemic velocity is 50 km/s. The hydrogen line data show an extended distribution and clear indications of rotation. In red light the system appears as a (possibly bar-shaped) nebulosity. From photographic photometry we tentatively determined a Holmberg size of 8 arc min. The object is probably Magellanic or irregular. At a distance of 3 Mpc its H I mass is 1.6 x 10 to the 9 solar masses. We estimate a total mass of 1.4 (+ or - 0.7) 10 to the 10 solar masses and a blue luminosity of 2(+ or - 1) 10 to the 9 solar luminosities. |
