Overview: Thirteen crucial benchmarks in the history of what may be the oldest science: Ancient awareness that the planets move, Copernican cosmology, Johannes Kepler's laws of planetary motion, Galileo's discovery of Jupiter's moons, Edmund Halley's comet prediction, William and Carolyn Herschel's galactic mapping, Einstein's General Theory of Relativity, Edwin Hubble's proof that the universe is expanding, Karl Jansky's discovery of galactic radio waves, Arno Penzias and Robert Wilson's detection of the cosmic microwave background, observations of gamma ray bursts, the discovery of extrasolar planets, and the "big rip" theory.