A crane lifts from its transporter beside the mobile service tower at Space Launch Complex 2 at Vandenberg Air Force Base.

A 20-ton crane lifts NASA's Orbiting Carbon Observatory-2, or OCO-2, from its transporter beside the mobile service tower at Space Launch Complex 2 at Vandenberg Air Force Base in California.

The spacecraft will be mated with the United Launch Alliance Delta II rocket inside the tower. Launch is scheduled for July 1. OCO-2 will collect precise global measurements of carbon dioxide in the Earth's atmosphere and provide scientists with a better idea of the chemical compound's impacts on climate change. Scientists will analyze this data to improve our understanding of the natural processes and human activities that regulate the abundance and distribution of this important atmospheric gas. To learn more about OCO-2, visit http://oco.jpl.nasa.gov. Photo credit: NASA/Randy Beaudoin