Examines key points in the development of astronomy, such as Greek astronomer Ptolemy's earth centered paradigm, Nicolas Copernicus' introduction of a sun centered solar system, and Isaac Newton's three laws of motion. Follows with the discovery of Neptune, Einstein's theories of Special and General Relativity, Hubble's expanding universe, plus discoveries of quasars, white dwarfs, neutron stars, pulsars, black holes, and astronomy's modern frontiers. Includes photographs, quiz, guide, and more.