Topic: Key Figures Unit: Sci. Rev.

Sci. Rev. Key Figures Copernicus: Polish Wrote On the Revolution of the Celestial Spheres Studied Ptolemy but disagreed with his theory that the universe was geocentric, meaning Earth at the center of the universe. Developed his own theory: the universe was heliocentric, meaning the Sun at the center of the universe. Did not publish his book until right before his death for fear of persecution. His theories became known as the Copernican system.

Sci. Rev. Key Figures Johannes Kepler: German astronomer Attempted to map the orbit of the planets but Mars did not move in circles like it was suppose thought to. Planets orbit the sun in elliptical (oval), not circular, orbits. Was the first to speak out in support of the Copernicus.

Sci. Rev. Key Figures Galileo Galilei: Famous for improving the telescope and using it to study the universe. With the telescope, he observed the craters and mountains of the moon. He also saw that many moons orbit Jupiter. He not only observed things in nature, he designed experiments to test them. Known as the Father of Experimental Science because he was the 1st to regularly use experiments. Major contributions to the study of mechanics: the study of objects and motion.

Sci. Rev. Key Figures Sir Isaac Newton: English Scientist Wrote, Principia Mathematica in 1687. Newton’s Law: one law of gravity and three laws of motion. Newton’s Laws became the foundation of nearly all scientific study. Created calculus. Proved that light is made up of all colors of the rainbow.

Sci. Rev. Key Figures Francis Bacon: English Scientist Scientist should observe the world & gather information about it. Conduct experiments to gather information. Develop theories to explain information & then test those theories with experiments. Science should be pursued in a systematic way; consistently and logically. Rene Descartes: French Philosopher Doubt everything until it can be proven with reason. World can trick people’s senses; people must use clear reason to establish proof. “I think therefore I am”