Vern Thorp, United Launch Alliance program manager, NASA missions, discusses the launch of NASA’s Orbiting Carbon Observatory-2 (OCO-2) onboard a ULA Delta II rocket, during a press briefing, Sunday, June 29, 2014, at the Vandenberg Air Force Base, Calif. OCO-2 will measure the global distribution of carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 is set to launch on July 1, 2014 at 2:59 a.m. PDT. Photo Credit: (NASA/Bill Ingalls)