ULA launches Delta IV Heavy rocket carrying NROL-44 mission after months of delays

CAPE CANAVERAL, Fla. - At 10 minutes past 8 p.m. EST, a United Launch Alliance (ULA) Delta IV Heavy rocket broke through the sound barrier, traveling over 1,000 mph as it soared over Florida's Atlantic Coast. 

Seconds earlier it had lifted off from Launch Complex-37 at Cape Canaveral Space Force Station, carrying with it a security satellite for the National Reconnaissance Office (NRO). It was the 142nd mission for United Launch Alliance and the 30th for the NRO.

The eight-and-a-half-hour countdown started at 9:45 a.m. under the guidance of ULA Launch Conductor Scott Barney. Retraction of the Mobile Service Tower began at 10:32 a.m., final configuring of the pad then followed and was cleared of all personnel. The "go" for fueling was given by ULA Launch Director Lou Mangieri at 3:33 p.m. Tanking operations were successfully performed as 470,000 gallons of liquid hydrogen and liquid oxygen were placed into the rocket’s eight tanks.

The clear to launch was given at 8:03 p.m. by NRO Mission Director Col. Chad Davis, who serves as the director of the NRO's Office of Space Launch.

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The launch has been reportedly been delayed several times since June. 

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