This book is the first complete account of the scientific life and work of Edwin Hubble, whose discoveries form the basis of all theories of the evolution of the universe. One of the outstanding astronomers of the twentieth century, Hubble studied the velocities or redshifts of galaxies and discovered that the universe is expanding. He convincingly proved that our galaxy is only one of countless galaxies and thus paved the way for the exploration of an immense world beyond the limits of our knowledge. The exploding universe proposed by Hubble, now termed the Big Bang, is used to explain the...