Inside the high bay of the Astrotech Space Operations facility at Vandenberg Air Force Base in California, a technician prepares NASA's Ice, Cloud and land Elevation Satellite-2 (ICESat-2) to be attached to the payload adapter, on Aug. 20, 2018. The satellite is being prepared for its scheduled launch from Space Launch Complex 2 at Vandenberg on the final United Launch Alliance 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 the Advanced Topographic Laser Altimeter System (ATLAS). ICESat-2 will help scientists investigate why, and how much our planet's frozen and icy areas, called the cryosphere, are changing in a warming climate.