The first half of the United Launch Alliance (ULA) Delta II rocket payload fairing is transported to the Vertical Integration Facility at Space Launch Complex 2 at Vandenberg Air Force Base in California, on June 4, 2018. NASA's Ice, Cloud and land Elevation Satellite-2 (ICESat-2) will launch later this year on the final Delta II rocket. ICESat-2 will measure the height of a changing Earth, one laser pulse at a time, 10,000 laser pulses a second. The satellite will carry a single instrument, the Advanced Topographic Laser Altimeter System. ICESat-2 will help scientists investigate why, and how much our planet's frozen and icy areas, called the cryosphere, is changing in a warming climate.