Discovery and exploration of the Solar System that moved through the sky. Although the Greek philosopher Aristarchus of Samos had speculated on a heliocentric reordering of the cosmos, Nicolaus Copernicus in the 16th century developed a mathematically predictive heliocentric system. His 17th-century successors, Galileo Galilei, Johannes Kepler, and Isaac Newton, developed a modern understanding of physics that led to the gradual acceptance of the idea that Earth moves around the Sun and that the planets are governed by the same physical laws that govern Earth. In more recent times, this led to the investigation of geological phenomena such as mountains and craters and seasonal meteorological phenomena such
Christianity in the 16th century the Reformed church in Geneva, which became an "unofficial capital" of Reformed Christianity in the second half of the 16th century. He exerted a remarkable amount of authority in the city and over the city council, such that he has (rather ignominiously) been called a "Protestant pope." Calvin established an eldership together with a consistory, where pastors and the elders established matters of religious discipline for the Genevan population. Calvin's theology is best known for his doctrine of (double) predestination, which held that God had, from all eternity, providentially foreordained who would be saved (the elect) and likewise who would