On Space Launch Complex 2 the Delta II rocket stands ready for fueling in preparation for launch.

On Space Launch Complex 2, the Delta II rocket stands ready for fueling in preparation for launch. The CALIPSO and CloudSat satellites are set to launch at 6:02 a.m. EDT on April 23 from Vandenberg Air Force Base (VAFB) on missions to study clouds and aerosols, tiny particles in the air. CALIPSO and CloudSat are set to fly into orbit aboard a Boeing Delta II rocket. The Delta II is designed to boost medium-sized satellites and robotic explorers into space. NASA selected a model 7420-10C for this mission, which is a two-stage rocket equipped with four strap-on motors and a protective 10-foot payload fairing. Photo credit: NASA/Bill Ingalls