Smoke rises from chimneys of coal-based power plants in the Sonbhadra District of Uttar Pradesh, India. The Washington Post/Getty Images hide caption

itoggle caption The Washington Post/Getty Images

Rajendra K. Pachauri speaks at the U.N. Climate Change Conference in Lima, Peru, on Dec. 11, 2014. He is stepping down as chairman of the Intergovernmental Panel on Climate Change. Juan Karita/AP hide caption

itoggle caption Juan Karita/AP

A Falcon 9 SpaceX rocket stands ready for a sunset launch from complex 40 at the Cape Canaveral Air Force Station in Cape Canaveral, Fla., on Sunday. It will be carrying aloft the DSCOVR satellite. John Raoux/AP hide caption

itoggle caption John Raoux/AP

NASA says this "blue marble" image is the most detailed true-color image of the entire Earth to date. NASA hide caption

itoggle caption NASA

Former Vice President Al Gore. Jon Kalish/NPR hide caption

itoggle caption Jon Kalish/NPR

Who will be Romney's VP? The naming of his running mate is likely going to come in mid-August, after his foreign trip and the conclusion of the Olympics. Ken Rudin collection hide caption

itoggle caption Ken Rudin collection