| Abstract | Radio emission from neutral hydrogen in the Sbc galaxy NGC 7320 has been detected with the radio telescope at Nan &y, France. An analysis of the observed proffle gives estimates of the hydrogen mass M1 (proportional to the square of the distance) and of the total mass MT (proportional to the distance). A comparison of the ratios MH and MT/LM with other Sbc galaxies whose distances are better known leads to the conclusion that NGC 7320 is most probably a dwarf system at a distance of about 10 Mpc. It is therefore wilikely that NGC 7320 is physically associated with the other four members of Stephan's Quintet (distance about 67 Mpc). The method of distance estimation used in this paper may be helpful in establishing membership of galaxies in other nearby multiple systems. Key words: galaxy cluster stabffity - galaxy distance estimates |
