Nature World: NASA is making final preparations for next month's launch of a spacecraft that will provide scientists with a better understanding of what's driving Earth's changing climate, specifically looking at carbon dioxide (CO2). The agency's Orbiting Carbon Observatory-2 (OCO-2) satellite is gearing up for its July 1 liftoff from Vandenberg Air Force Base in California. The mission - one of five new NASA Earth science missions set to launch in 2014 - is designed to give a comprehensive look at atmospheric...