Abstract

Results are presented on the optical photometry of two supernovae, 1980N and 1981D, in the D-type galaxy NGC 1316 (Fornax A). These observations are combined with earlier data to construct definitive light curves of the two supernovae, and the light curves and the color evolution of both supernovae are compared with average curves constructed by previous investigators. It is found that the shapes of the UBV light curves of 1980N closely resembles those of the type Ia prototype SN 1981B. The optical spectrum of SN 1980N taken 30 days after the B maximum is virtually identical to a spectrum of SN 1981B obtained at the same point in its evolution. These findings support claims that the majority of the type Ia supernovae form a highly homogeneous class of objects.