The U.S. Air Force conducted an early-morning suborbital test of an unarmed Minuteman III intercontinental ballistic missile, or ICBM, on Wednesday (Sept. 7).
Air Force Global Strike Command launched the ICBM from Vandenberg Space Force Base in California at 1:13 a.m. PT (4:13 a.m. ET; 0913 GMT). The test was conducted to "validate and verify the safety, security, effectiveness and readiness of the weapon system," according to a Space Force statement (opens in new tab).
The Minuteman III ICBM carried three undisclosed test reentry vehicles, according to a Space Force video (opens in new tab) released following the test. A reentry vehicle is the payload of an ICBM that reenters the atmosphere following a launch, typically a nuclear warhead, although hypersonic glide vehicles will surely become common reentry vehicles as they continue to be developed. The missile traveled 4,200 miles (6,759 kilometers) at hypersonic speeds reaching 15,000 mph (24,140 kph), or about 4 miles (6.4 km) per second.
The missile fired in the test launch was chosen at random from a stockpile at F.E. Warren Air Force Base in Wyoming, disassembled and shipped to Vandenberg, where it was reassembled prior to launch. These tests are typically planned years in advance, and pre-launch notifications were sent to the Russian government in accordance with the New START arms control treaty.
Col. Bryan Titus, Space Launch Delta 30 vice commander, said in the statement that these launches "demonstrate the readiness of U.S. nuclear forces and provide confidence in the lethality and effectiveness of the nation's nuclear deterrent."
Space Launch Delta 30 oversees all launches from the U.S. west coast, including those that place satellites into polar orbits. "The Airmen and Guardians who perform this vital mission are some of the most skillfully trained and dedicated personnel in America's Air and Space Force," Titus added.(opens in new tab)
Netherlands-based satellite tracker Marco Langbroek shared images via Twitter (opens in new tab) of the navigational warnings issued prior to the launch that depict the ICBM's path from Vandenberg to the Ronald Reagan Ballistic Missile Defense Test Site in the Kwajalein Atoll in the Marshall Islands.
The Minuteman III, or LGM-30G, was first deployed in 1970 and is scheduled to be phased out by 2030 and replaced with the upcoming LGM-35A Sentinel ICBM (opens in new tab) currently under development.