Cosmology is the study of how the universe has evolved and will continue to evolve over the years. The most widely accepted theory for how the universe began is the Big Bang Theory. The Big Bang Theory is widely accepted today based on the current evidence. One of the most important pieces of evidence to provide support for the Big Bang came in the early 1930’s when a scientist by the name of Edwin Hubble proved that the galaxies where redshifting. A second piece of evidence came in 1964 when two scientists discovered cosmic background radiation. Scientists theorize that this radiation was energy leftover from the explosion 13.7 billion years ago.