Graphic illustrating the evolution of satellites designed to measure the Cosmic Microwave Background (CMB), radiation left over from the big bang. Each panel shows a 10-square-degree patch of all-sky map created by the satellite above. As technology advanced from the Cosmic Background Explorer (COBE), launched in 1989, to the Wilkinson Microwave Ansiotropy Probe (WMAP), 2001, and finally to Planck, 2009, more and more variations (called ansiotropies) become visible. This is significant because these variations reveal important information about the state of the universe: its origins, makeup, and future.