Galileo and the History of the Telescope

The invention of the telescope in the early 17th century marked a critical point in our understanding of our place in the Universe. In observing the Moon, the Sun, Jupiter, and Venus, Galileo was able to disprove the Aristotelian and Ptolemaic model that saw the heavens as an unchanging, perfect realm, and where all orbits centered on the Earth. Instead, Galileo found a solar system much more accurately described by the heliocentric model, in which Earth and the other planets revolved around the Sun, and where the "heavenly" bodies were no more perfect than was the Earth. However, the heliocentric worldview was firmly opposed by the Catholic Church, which placed Galileo on trial for his support of this model and the publication of his book "Dialog on the Two Chief World Systems," which clearly favored the heliocentric view. Galileo remained in house arrest for the rest of his life, and not until 1992 did the Catholic Church admit that the trial of Galileo had been a mistake, and that the Church had been "incapable of dissociating faith from an age-old cosmology." A wonderful resource on the history of the telescope, Galileo, and Galileo's observations can be found here.