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

Follow the key events of the Falcon 9 rocket’s ascent to orbit 60 satellites for SpaceX’s Starlink broadband network.

A team of United Launch Alliance and NASA engineers worked through Delta 2 launch day fueling procedures during a simulated countdown Wednesday for what should be the second-to-last time before the venerable rocket’s final liftoff next month from California’s Central Coast.

United Launch Alliance’s final Delta 2 rocket is now on display at the Kennedy Space Center Visitor Complex in Florida, a monument to an industry workhorse that helped build the GPS navigation satellite fleet and enabled a new era of Mars exploration.