A United Launch Alliance (ULA) Delta IV Heavy rocket carrying the NROL-91 mission for the National Reconnaissance Office (NRO) lifted off on Sept. 24 at 3:25 p.m. PDT from Space Launch Complex-6 at Vandenberg Space Force Base. To date ULA has launched 153 times with 100 percent mission success.
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The Delta IV Heavy rocket launches the NROL-91 mission. Photo by United Launch Alliance