| Abstract | A comparison of the southern galaxies NGC 1512 and NGC 1510, suggesting a physically interacting pair, is presented. Photographs of the two galaxies show that the central ring of the NGC 1512 is distorted into an ovoid and that the spiral arms, extending up to 8.5 deg of arc, are also distorted. It is found that the mass-to-luminosity ratio (31 + or - 11 M/L) of the NGC 1512 is high and abnormally rich in hydrogen, relative to its luminosity and optical area. Due to a lack of optical features of an extended gas distribution, it is suggested that the star formation at the outskirts of this galaxy was suppressed by some unknown mechanism. Methods of determining this mechanism are suggested, including high resolution observations of neutral hydrogen, and spectroscopy. It is concluded that the emission line spectrum and unusually blue colors of the NGC 1510 can best be explained by star formations in material recently accreted from its neighbor. |
