Galileo Galilei’s TrattatoDella Sfera Ovvero Cosmografia and some cosmographies and treatises on the sphere of the 16th century

Abstract

This paper analyses a work composed by Galileo for his students, probably written during the period when he taught in Padua and published posthumously. The Trattato della sfera ovvero cosmografia presents and argues for the geocentric astronomy. It was mainly inspired by Johannes de Sacrobosco’s De sphæra. Comparing Galileo’s work to contemporary commentaries to Sacrobosco’s treatise, this paper examines the sources he used, his knowledge of the geocentric heritage, and discusses whether he pointed out flaws of this tradition and attempted to correct them