Greatest Discoveries with Bill Nye

Nye covers Einstein's theory of general relativity, demonstrates how Hubble determined that the universe is expanding, and discusses the 20th-century advancements that help us understand gamma ray bursts, black holes, pulsars, and quasars. Highlights include Edmond Halley, whose discovery of comets orbiting the sun proved that gravity works in space, and Alexander and Caroline Herschel, whose map of the sky brought new understanding of the universe.