Giovanni Domenico Cassini was born in Perinaldo. An Italian astronomer, he also worked for a long period in France. Cassini discovered four of Saturn’s moons along with the principal division within Saturn’s rings, the Cassini Division, named after him. He also created a meridian line along the nave flooring in the Basilica of St. Petronius in Bologna, replacing the one that the Dominican Egnazio Danti had established a century earlier. Cassini’s meridian, due to its ingenuity and size, served as a point of reference for all succeeding planar meridians, among them that of St. Mary Major in Rome, commissioned by Pope Clement XI in order to verify the corrected dates introduced by the Gregorian calendar. Cassini also has an interplanetary robotic spacecraft named after him, the Cassini-Huygens, which entered Saturn’s orbit on July 1, 2004.