English: NASA Associate Administrator for the Science Mission Directorate Thomas Zurbuchen, left, and other NASA leadership listen as Julianna Scheiman, director for civil satellite missions at SpaceX, center, gives a tour of the hangar where the Falcon 9 rocket and DART spacecraft are being readied for launch, Monday, Nov. 22, 2021, at Vandenberg Space Force Base in California. DART is the world’s first full-scale planetary defense test, demonstrating one method of asteroid deflection technology. The mission was built and is managed by Johns Hopkins APL for NASA’s Planetary Defense Coordination Office. Photo Credit: (NASA/Bill Ingalls)