Imagine observing the universe in its early stages, about 380,000 years after birth. Using NASA's Cosmic Background Explorer (COBE) satellite, launched in 1989, John C. Mather and George F. Smoot did just that, and eventually helped cement the Big Bang theory of the universe and launched a broader understanding of the origin of giant clusters of galaxies. For their work they shared the 2006 Nobel Prize for Physics. Find related documents and resources with additional information on both Mather and Smooth at the OSTI DOE R&D Accomplishments website. DOE R&D Accomplishments is a central forum for information about significant outcomes of past DOE R&D widely recognized as remarkable advancements in science.