A Minotaur II+ rocket exploded just after launching on a test mission from California's Vandenberg Space Force Base early Thursday morning (July 7).
The explosion occurred about 11 seconds after liftoff, which took place at 2:01 a.m. EDT (0601 GMT; 11:01 p.m. local California time on July 6), according to a short press release issued by Vandenberg officials.
No injuries were reported, and "the debris was contained to the immediate vicinity of the launch pad," the release stated, adding that an investigative review board will determine the cause.
"We always have emergency response teams on standby prior to every launch," Col. Kris Barcomb, Space Launch Delta 30 vice commander and the decision authority for this launch, added in the statement. "Safety is our priority at all times."
Related: What is the U.S. Space Force?
The Minotaur II+ launch was intended to support the development of a re-entry vehicle for the U.S. Air Force known as Mk21A, which will eventually ride on an LGM-35A Sentinel intercontinental ballistic missile (ICBM) that is also in the works, according to CBS News.
"The test launch was intended to demonstrate preliminary design concepts and relevant technologies in operationally realistic environments, according to Air Force Nuclear Weapons Center officials," CBS reported.
The Sentinel program is intended to replace the "aging" Minuteman III ICBM, according to the center, which is helming the project.
"Although certain components and subsystems have been upgraded since the Minuteman III ICBM system first became operational in the early 1970s, most of the system's fundamental infrastructure still uses the original equipment," Nuclear Weapons Center officials wrote in a description of the Sentinel ICBM program.
Once ready, the new Sentinel ICBMs will take the place of 400 Minuteman III ICBMs stationed at Air Force bases in Wyoming, Montana and North Dakota, Air Force officials said.
The plan is to upgrade launch facilities, missile alert and communication systems, and other infrastructure and technology to "support the new Sentinel weapon system," the description added. "The Minuteman III ICBMs will be decommissioned, which requires demilitarization and disposal activities."
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Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. She was contributing writer for Space.com for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, "Why Am I Taller?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015; her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon: https://qoto.org/@howellspace