The United Launch Alliance (ULA) Delta program, which lasted 60 years, ended Tuesday with the successful launch of the final Delta IV Heavy rocket at 11:53 a.m. from Space Launch Complex-37 at Cape Canaveral Space Force Station, Florida. The rocket was carrying the NROL-70 mission for the National Reconnaissance Office (NRO).

ULA said that although this marks the end of the Delta era, it initiates the future of heavy lift on ULA's next-generation Vulcan rocket.

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"Thank you to our teammates past and present for their dedication to these critical national security missions," said Gary Wentz, ULA vice president of Government and Commercial Programs. "The Delta IV Heavy rocket was a workhorse for the NRO, launching 12 missions delivering critical national security payloads. The NROL-70 mission marked our 35th successful launch with the NRO, and we look forward to continuing our partnership in launching future national security space missions."

ULA did not disclose the payload's nature due to national security concerns—only that it is for the NRO, which develops and operates the world's most capable reconnaissance satellite systems to collect intelligence for U.S. national security and support disaster relief and humanitarian efforts.

"The Delta rocket played a pivotal role in the evolution of space flight since the 1960s," said Tory Bruno, ULA's president and CEO. "This final Delta mission signals ULA's evolution to the new Vulcan rocket, providing even higher performance than our three-core Delta IV Heavy rocket in a single-core rocket to launch heavy-class missions for the nation. We will continue to deliver our superior reliability and unprecedented orbital precision for all our customers across the national security, civil, and commercial markets."

U.S. Rep. Dale Strong (R-Monrovia) congratulated ULA on the launch.

ULA's next launch is the crew flight test mission for Boeing's CST-100 Starliner spacecraft as part of NASA's Commercial Crew program. It is planned for no earlier than May 6.

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