- brahe: years worth of obervation of the sky on an island
- copernicus: heliocentric theory; polish
- galileo: italian astronomer; used telescope to observe rotation of the sun; promoted copernican system; prosecuted at the Inquisition
- geocentric theory: earth is center of universe
- heliocentric theory: sun is the center of the universe
- idea of astronomy during sci rev: rarional explanations of the universe; proof that humans were not the center of all things; planetary motion
- kepler: took brahe's work and came up with info againsst ptolemy; laws of planetary motion
- previous views of astronomy before the scientific revolution: ptolemy and aristotle; ancient, medieval science; earth at the center of the universe; god held the world together