The skies have inspired reflection on the vastness of space, the wonder of creation, and humankind's role in the universe. In just over 100 years, science has moved from almost total ignorance about the actual distances to the stars and earth's place in the galaxy to contemporary knowledge about the enormous size, mass and the age of the universe. We are reaching the limits of observation, and therefore the limits of human understanding. Beyond lies only imagination, seeded by the theories of physics. Here, science writers David and Matthew Clark tell the stories of both well-known and the unsung heroes who played key roles in these discoveries. These true accounts reveal ambitions, conflicts, failures, as well as successes, as the scale and age of the universe were finally established. Few areas of scientific research have witnessed such drama in the form of geo clashes, priority claims, or failed (or even falsified) theories as that resulting from attempts to measure the universe.