Ian Stewart&s up-to-the-minute guide to the cosmos moves from the formation of the Earth & its Moon to the planets & asteroids of the solar system & from there out into the galaxy & the universe He describes the architecture of space & time dark matter & dark energy how galaxies form why stars implode how everything began & how it will end He considers parallel universes what forms extra-terrestrial life might take & the likelihood of Earth being hit by an asteroid Mathematics Professor Stewart shows has been the driving force in astronomy & cosmology since the ancient Babylonians He describes how Kepler&s work on planetary orbits led Newton to formulate his theory of gravity & how two centuries later irregularities in the motion of Mars inspired Einstein&s theory of general relativity In crystal-clear terms he explains the fundamentals of gravity spacetime relativity & quantum theory & shows how they all relate to each other Eighty years ago the discovery that the universe is expanding led to the Big Bang theory of its origins This in turn led cosmologists to posit features such as dark matter & dark energy But does dark matter exist? Could another scientific revolution be on the way to challenge current scientific orthodoxy? These are among the questions Ian Stewart raises in his quest through the realms of astronomy & cosmology