United Launch Alliance’s Delta IV Heavy rocket will try again next week to launch the mysterious NROL-71 mission for the National Reconnaissance Office following two scrubs. Friday’s initial attempt was scrubbed after ULA noted an issue with the hold-fire circuitry – specifically a redundant communication link between the control center and the launch site – required further work. Following a 24 hour recycle, all was proceeding to plan until T-7 seconds when an abort was triggered. It is not yet known when the next attempt will take place.Like most activities conducted by the United States National Reconnaissance Office (NRO), specifics of the NRO Launch 71 (NROL-71) mission are classified. The NRO is the organization that operates America’s fleet of reconnaissance and intelligence-gathering satellites, using a variety of spacecraft types and surveillance techniques to support national defense and security.