Live coverage of the countdown and launch of a United Launch Alliance Atlas 5 rocket from pad 41 at Cape Canaveral Space Force Station in Florida. The mission, known as USSF 8, will launch two U.S. Space Force satellites for the Geosynchronous Space Situational Awareness Program. Text updates will appear automatically below. Follow us on Twitter.

United Launch Alliance’s first mission of the year will debut a new configuration of the company’s workhorse Atlas 5 rocket when it lifts off at 2 p.m. EST (1900 GMT) Friday from Cape Canaveral Space Force Station, Florida.

The rocket, featuring a wide fairing and a single solid rocket booster, will carry two U.S. military tracking and inspection satellites into geosynchronous orbit during a nearly seven-hour flight sequence.

The 196-foot-tall (59.7-meter) Atlas 5 rocket is set to take off from pad 41 at Cape Canaveral. Its RD-180 main engine and single strap-on booster will generate about 1.2 million pounds of thrust at liftoff, powering the Atlas 5 due east over the Atlantic Ocean.

You can watch our live launch coverage on this page beginning at 11:30 a.m. EST (1630 GMT).

The payloads on-board the rocket are the fifth and sixth satellites for the U.S. Space Force’s Geosynchronous Space Situational Awareness Program.

The GSSAP satellites are designed to help the military track and observe objects in geosynchronous orbit more than 22,000 miles (nearly 36,000 kilometers) over the equator. The first four GSSAP satellites launched in pairs on Delta 4 rockets in 2014 and 2016.

In 2017, the military confirmed it ordered two additional GSSAP satellites from Orbital ATK, now part of Northrop Grumman. Those satellites, each the size of a compact car, are mounted side by side inside the Atlas 5 rocket’s payload fairing for launch Friday.

ULA will use a unique configuration of its workhorse Atlas 5 launcher for the mission, which the Space Force has designated USSF 8.

The Atlas 5 will be fitted with one strap-on solid rocket booster supplied by Northrop Grumman, a 5.4-meter (17.7-foot) diameter payload fairing provided by RUAG Space, and a single RL10 engine from Aerojet Rocketdyne on the rocket’s Centaur upper stage.

This version of the Atlas 5 is known as the “511” configuration, with the first number denoting the size of the payload fairing, the second number representing the number of solid rocket booster, and the third digit the number of engines on the Centaur stage.

The placement of just one strap-on booster on the side of the Atlas 5’s first stage will give the rocket asymmetrical thrust as it climbs off the pad. Atlas 5 missions have flown with a single solid rocket booster before, but those flights used the smaller 4-meter-wide payload fairing option.

The Atlas 5 comes in 11 different configurations, each optimized to haul satellites of a certain size.

Tory Bruno, ULA’s CEO, calls the “511” version of the Atlas 5 the “Big Slider.” Its launch Friday will likely be the only flight of the Atlas 5-511 configuration.

“We call it the ‘Big Slider’ because if you watch the launch, you’re going to see it kind of power slide off the pad because of this asymmetric torque,” Bruno said in a video posted on YouTube by ULA. “A lot of you wonder how do you fly that. That nozzle (of the solid rocket booster) is canted to pass through the average center of gravity, and the RD-180 has tremendous control authority with its thrust vector system, and it can overcome that and compensate for it, and this is just the right amount of energy to carry these two payloads to their very cool mission of space surveillance.”

Read our mission preview story for details.

ROCKET: Atlas 5 (AV-084)

MISSION: USSF 8

PAYLOAD: GSSAP 5 and GSSAP 6 space surveillance satellites

LAUNCH SITE: SLC-41, Cape Canaveral Space Force Station, Florida

LAUNCH DATE: Jan. 21, 2022

LAUNCH TIME: 2 p.m. EST (1900)

WEATHER FORECAST: 80% chance of acceptable weather

BOOSTER RECOVERY: None

LAUNCH AZIMUTH: East

TARGET ORBIT: Approximately 22,440 miles, 0.0 degrees inclination

LAUNCH TIMELINE:

T-00:00:02.7: RD-180 ignition T+00:00:01.0: Liftoff T+00:00:06.9: Begin pitch/yaw maneuver T+00:00:57.8: Mach 1 T+00:01:07.4: Maximum aerodynamic pressure (Max-Q) T+00:02:00.5: Solid rocket booster jettison T+00:03:30.0: Payload fairing jettison T+00:04:21.2: Atlas booster engine cutoff (BECO) T+00:04:27.2: Atlas/Centaur stage separation T+00:04:37.1: Centaur first main engine start (MES-1) T+00:13:07.8: Centaur first main engine cutoff (MECO-1) T+01:09:30.4: Centaur second main engine start (MES-2) T+01:13:37.0: Centaur second main engine cutoff (MECO-2) T+06:31:12.0: Centaur third main engine start (MES-3) T+06:32:59.3: Centaur third main engine cutoff (MECO-3) T+06:35:48.3: GSSAP 5 spacecraft separation T+06:45:20.3: GSSAP 6 spacecraft separation

MISSION STATS:

673rd launch for Atlas program since 1957 374th Atlas launch from Cape Canaveral 262nd mission of a Centaur upper stage 239th use of Centaur by an Atlas rocket 508th production RL10 engine to be launched 38th RL10C-1 engine launched 97th flight of an RD-180 main engine 91st launch of an Atlas 5 since 2002 35th U.S. Air Force/Space Force use of an Atlas 5 9th GEM-63 solid rocket boosters flown 75th launch of an Atlas 5 from Cape Canaveral 1st Atlas 5 launch of 2022 133rd Evolved Expendable Launch Vehicle flight 148th United Launch Alliance flight overall 83rd Atlas 5 under United Launch Alliance 106th United Launch Alliance flight from Cape Canaveral 33rd 500-series flight of the Atlas 5 1st Atlas 5 to fly in the 511 configuration 102nd launch from Complex 41 75th Atlas 5 to use Complex 41 4th orbital launch overall from Cape Canaveral in 2022