Video: Tower rollback prior to launch of Mars Pathfinder atop a Delta 2

A Delta 2 rocket has lifted off from California’s Central Coast on Saturday with a NASA environmental satellite designed to improve flood and drought forecasts, map moisture in Earth’s soils, and track the planet’s water cycle.

The step-by-step stacking of United Launch Alliance’s final Delta 2 rocket was completed in June at Vandenberg Air Force Base in California for liftoff Sept. 15 with an Earth science satellite for NASA.

The next Delta 4-Heavy rocket was raised vertical Friday at Cape Canaveral, signaling the start of a comprehensive series of pre-flight tests before liftoff next year with a top secret U.S. government spy satellite.