Watch ULA’s most powerful rocket launch a classified spy satellite

Just before midnight on Tuesday, the United Launch Alliance is set to launch its most powerful rocket from Cape Canaveral, Florida, lofting a classified spy satellite for the National Reconnaissance Office. The mission is finally ready to fly a full month after the rocket’s first launch attempt, which was aborted just three seconds before liftoff.
The rocket going up on ULA’s mission is the Delta IV Heavy, a giant vehicle that consists of three rocket cores strapped together to provi