The Southern Sky and the Renovation of the Ptolemaic Tradition in Sixteenth-Century Italian Astrologers

This article examines the use of astronomical observations of the austral sky in treatises written by Italian astrologers during the sixteenth century. The references made to navigators’ accounts and diagrams of southern stars in the works of Agostino Nifo, Girolamo Cardano, Francesco Giuntini and Francesco Pifferi show their attempts to include previously unknown stars in Ptolemaic framing. Although this approach implies the defence of traditional astrology by recognising the need to broaden its contents, none of the authors studied here put forward an astrological interpretation of the new information available.