The moon, a disc to the naked eye, was revealed to have a mountainous surface, covered with craters, basins, and peaks, much like the earth itself. This discovery came as a shock, both to conventional science and to the Church. And then, in January 1610, Galileo's telescope revealed four of the nine moons of Jupiter; these moons "move... around another very great star (Venus)," he wrote, in the same way as Mercury and Venus, and peradventure the other known planets, move around the sun." At the time, most scientists believed that the Moon was a smooth sphere, but Galileo discovered that the Moon has mountains, pits, and other features, just like the Earth.When Galileo pointed his telescope at Jupiter, the largest planet in our solar system, he made a startling discovery. The planet had four "stars" surrounding it. Within days, Galileo figured out that these "stars" were actually moons in orbit of Jupiter. Galileo's telescope revealed four of the nine moons of Jupiter; these moons "move... around another very great star in the same way as Mercury and Venus, and peradventure the other known planets, move around the sun. This was concrete evidence for Copernicus's system, which had long been confined to the realm of mathematical models. If Jupiter had…