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Jam-Resistant US Military Communications Satellite Lifts Off in Midnight-Hour Launch

An advanced U.S. military communications satellite soared into space in the midnight hour Wednesday (Oct. 17), lighting up the sky over Florida as it launched into orbit.

A United Launch Alliance (ULA) Atlas V rocket launched the satellite, known as Advanced Extremely High Frequency 4 (AEHF-4), at 12:15 a.m. EDT (0415 GMT) from a pad at Cape Canaveral Air Force Station. AEHF-4 is an advanced jam-resistant and nuclear-hardened satellite designed "to provide survivable, global, secure, protected and jam-resistant communications for high-priority military forces," according to a U.S. Air force mission description.

After a smooth liftoff, the Atlas V carrying AEHF-4 shed five strap-on boosters and placed the satellite in an initial orbit with its Centaur upper stage. The Centaur deployed AEHF-4 in its final geostationary orbit about 22,300 miles (35,888 kilometers) above Earth about 3.5 hours after liftoff. [The Most Dangerous Space Weapons Ever]

A United Launch Alliance Atlas V rocket launches the AEHF-4 satellite for the U.S. Air Force from Cape Canaveral Air Force Station in Florida in the early-morning hours of Oct. 17, 2018. (Image credit: ULA)

"The mission of AEHF is to provide survivable protected communications for the military's high-priority assets on the ground, at sea and in the air," Maj. Matthew Getts of the Air Force's Space and Missile Center in Los Angeles said during commentary after the AEHF-4 launch. "It also enables the president of the United States and combatant commanders to control their tactical and strategic forces through all levels of war and all phases of conflict."

Built by Lockheed Martin, AEHF-4 is a $1.8 billion communications satellite designed to help replace the U.S. military's aging Milstar constellation. As its name suggests, AEHF-4 is the fourth satellite in the series, which will feature six spacecraft in all when complete. The first AEHF satellite launched in 2010.

"AEHF-4 that we just launched off the ground will complete the fully operational constellation for AEHF," Getts said. AEHF-5 is currently scheduled to launch in July of 2019, he added.

The Advanced Extremely High Frequency 4 communications satellite for the U.S. military is the fourth in a six-satellite constellation. (Image credit: Lockheed Martin)

The U.S. Defense Department has several partners in the AEHF program. They include the military forces of the United Kingdom, the Netherlands and Canada. U.S. officials are also in negotiations with Australia's defense department for a potential partnership, Getts added.

Today's AEH-4 launch marked the 131st launch for ULA and its 50th launch for the Air Force. ULA's next mission will be the launch of the classified NROL-71 spy satellite for the U.S. National Reconnaissance Office.

That mission will launch from California's Vandenberg Air Force Base later this year, ULA representatives said.

Editor's Note: This story was updated at 10:15 a.m. EDT with the news of successful satellite deployment.

Email Tariq Malik at or follow him @tariqjmalik. Follow us @Spacedotcom and on Facebook. Original article on

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Tariq is the Editor-in-Chief of and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. To see his latest project, you can follow Tariq on Twitter.