Some of the key players of the scientific revolution were Nicolaus Copernicus (1473–1543), Ptolemy (90–168 C.E., who was not of this period, but highly relevant to it), Galileo Galilei (1564–1642), Johannes Kepler (1571–1630), Francis Bacon (1561–1626), Robert Boyle (1627–1691), and Isaac Newton (1643–1727).