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.
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.