Rocket repurposed from intercontinental ballistic missile launches secret US spy satellites to orbit from California

For the first time in nearly a decade and a half, a Minotaur has streaked through Californian skies.

A Minotaur IV rocket lifted off from the Golden State’s Vandenberg Space Force Base today (April 16) at 3:33 p.m. EDT (1633 GMT; 12:33 p.m. local California time), kicking off the NROL-174 mission for the U.S. National Reconnaissance Office (NRO).

It was the first launch of a Minotaur from the site since 2011, the NRO said via X.

The Minotaur rocket family, built by aerospace giant Northrop Grumman, consists of repurposed intercontinental ballistic missiles. The Minotaur IV is a four-stage vehicle that stands 78 feet (24 meters) tall.

A Minotaur IV hadn’t flown since a July 2020 mission that launched from Virginia. But today, the rocket got back to work and did its job as planned.

“The NROL-174 Minotaur IV rocket was once a Peacekeeper ICBM that sat watch 24/7 in support of our nation’s nuclear deterrent,” NROL-174 Mission Director Laura Robinson, deputy director of the NRO Office of Space Launch, said in a post-launch statement.

“Now modified for space launch, it completed its final mission of placing a national security payload on orbit, a credit to the decades-long dedication of those who were part of the missile’s early development, maintenance and operations, and innovative conversion into the Minotaur IV rocket,” Robinson added. “It was truly a team effort.”

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The NRO builds and operates the nation’s fleet of spy satellites. The agency reveals few details about these craft and their capabilities, so it’s no surprise that NROL-174 is shrouded in secrecy.

The NRO’s press kit offers a vague explanation, saying the mission consists “of multiple national security payloads designed, built and operated by the NRO.”

NROL-174 flew via the U.S. Space Force‘s Rocket Systems Launch Program (RSLP). According to the press kit, the RLSP “primarily launches more risk-tolerant experimental, research and development, responsive space and operational missions.”