UBVRI Photometry of SN 1987A: The First 156 Days From Cerro Las Campanas

This paper reports on previously unpublished UBVRI photoelectric observations of Supernova 1987A, consisting of 74 nights spanning the first 156 days of the event. The first observations come just one day after core collapse. The nightly mean magnitudes and colors have a typical error of <= 0.01 mag after transformation to the Cousins UBVRI system. Differences with respect to previously published datasets are discussed.