Watch Atlas V Rocket Do Live 'Power-Slide' Launch in U.S. Military Mission

Private U.S. space company United Launch Alliance (ULA) is due to launch a pair of military satellites into orbit today on an unusually-configured Atlas V rocket—and liftoff will be broadcast live.

The mission, called USSF-8, will launch from the Cape Canaveral Space Force Station in Florida at 2 p.m. ET on Friday. Live coverage, hosted by ULA, is set to begin at around 1:40 p.m. ET via the ULA YouTube channel.

The purpose of USSF-8 is to launch two identical space surveillance satellites on behalf of the U.S. Space Force. They'll be put into orbit around 22,300 miles above the equator and provide what the ULA calls "neighborhood watch services" to improve spaceflight safety in their particular orbit.

The rocket that will launch them there, the Atlas V, is the ULA's go-to workhorse launch vehicle, which has been operating for nearly 20 years. Its inaugural launch took place in 2002, and since then has been behind dozens of space missions from commercial and military satellite launches to probes destined for other planets.

Although the rocket is far from new, today's launch will be the first time that the Atlas V will be used in its so-called "Big Slider" configuration.

The unusual thing about today's launch is that in addition to the rocket's main RD-180 engine system, lift-off will be assisted by a single solid rocket booster attached to the side of the vehicle.

This means the vehicle will essentially be unbalanced at launch and, as ULA CEO Tory Bruno said in a Twitter video this week, will "power-slide" off the launch pad due to its asymmetrical torque. However, trajectory will be corrected by the RD-180 engine which is capable of redirecting its own thrust to compensate.

The entire mission is set to last just under 8 hours, with the two satellites being released around 6.5 hours in.

Unlike the newer Falcon 9 rocket operated by competing private space firm SpaceX, the Atlas V is expendable.

The days of the Atlas V are due to come to a close soon as ULA transitions to its newer rocket, Vulcan, which is due to make a debut launch later this year.

Speaking to The Verge in 2021, ULA CEO Tory Bruno said all of the company's Atlas V rockets had been sold, meaning only a limited number of launches remain. The U.S. curbed its reliance on the Atlas V in part due to the fact that its RD-180 engines were Russian-made, and the U.S. had placed sanctions on Russia following its annexation of Crimea in 2014.

Atlas V
An Atlas V rocket seen in December, 2019 at Cape Canaveral Air Force Station in Florida with a Boeing Starliner capsule on top. The ULA rocket has been in use for nearly 20 years. Joel Kowsky/NASA/Getty