Galileo got a teaching position at the University of Padua and there he taught geometry and astronomy. In 1600, he met the woman who would be the mother of his kids, a Venetian woman named Marina Gamba. Albeit they did not get married to each other, they had two daughters, named Virginia and Livia, and a son of a named Vincenzo. Four years after meeting Marina, Galileo developed the universal law of acceleration after polishing his theories on motion and falling objects.
In July of 1609, Galileo has heard of an invention that could magnify objects three times made by a Dutch eyeglass maker, Hans Lippershey, and he made one of his own better version. During the autumn season of the same year, Galileo decided to turn his telescope up toward the heavens. A year after, he published a small booklet entitled “The Starry Messenger” that was about his discoveries that was found with his telescope. The booklet included his discoveries on the moon’s spherical shape and rough texture, and Venus’s phases that supported Copernicus’ theory of a sun-centered solar system. Furthermore, it also revealed Galileo’s discovery of Jupiter’s moons and how they revolve