Galileo offered first-hand telescopic demonstrations to influential colleagues and supporters across Venice and Tuscany. In early 1611, Galileo visited Rome, invited by Clavius and the Jesuits. Jesuit astronomers of the Rome College (Collegio Romano) looked through Galileo’s telescopes and confirmed his discoveries, certifying their validity to Cardinal Robert Bellarmine. Clavius indicated that astronomical views needed revision. Ptolemy’s system was dead, so far as mathematical astronomers were concerned. The Jesuits feasted and honored Galileo, offering him speeches and gifts as the leading light of Tuscany.