| Abstract | The distribution and velocity field of neutral hydrogen (H I) associated with the irregular galaxy IC 10 was studied using observations made with the 100-meter radio-telescope at Effelsberg. An enormous envelope extending to a diameter of about 10 minutes at a surface density of 3.6 times 10 to the 18th atoms per cubic centimeter was found. Assuming a distance of 1 Mpc, and low optical depth, the total H I mass of IC 10 is calculated to be 270 million solar masses. The global parameters such as total mass to luminosity, H I mass to luminosity, and relative H I content are within normal limits for late-type galaxies (Roberts, 1975). The velocity field gradient is differently oriented at small and large scale, and large line widths in the outer areas of the H I distribution are more pronounced than in the central area. |
