CAPE CANAVERAL, Fla. A United Launch Alliance (ULA) Atlas V rocket took to the skies Thursday afternoon (March 26), delivering a highly advanced communications satellite to orbit for the U.S. Space Force.

The rocket, outfitted with five strap-on solid rocket boosters, leapt off the pad from Space Launch Complex 41 at Cape Canaveral Air Force Station here at 4:18 p.m. EDT (2018 GMT), near the middle of a planned two-hour window.

Perched atop the rocket was the sixth Advanced Extremely High Frequency (AEHF-6) satellite. AEHF-6 is the final satellite in the AEHF constellation, and it will provide jam-proof communications including real-time video between U.S. national leadership and deployed military forces.

Related: Blastoff! US Space Force's 1st launch is the AEHF-6 satellite (video)

The AEHF constellation is built by Lockheed Martin and consists of six secure military communications satellites that will replace the military's aging Milstar constellation. Working in tandem, the satellites will provide coverage from geostationary Earth orbit, about 22,200 miles (35,700 kilometers) above the planet. This orbit allows spacecraft to drift along in sync with Earth's rotation, providing constant coverage over the same part of the planet.

Today's launch marks the 83rd flight of an Atlas V and the 11th overall in the 551 configuration. The most powerful version of the Atlas V, the 551 comes with five solid rocket boosters, a 16.5-foot-wide (5 meters) payload fairing and a single engine Centaur upper stage.

The 13,600-lb. (6,168 kilograms) AEHF-6 is the first National Security Space payload to launch under the recently established U.S. Space Force, which was signed into existence by President Donald Trump in December 2019. Just like the Marine Corps is part of the Department of the Navy, the Space Force will operate under the Department of the Air Force.

Rather than deploying soldiers in space, the new military branch will focus on national security and preserving the satellites and vehicles that are dedicated to international communications and observation, U.S. officials have said.

Originally scheduled to fly on March 13, Thursday's launch was pushed back after an off-nominal valve reading occurred during prelaunch processing. Crews removed the suspect hardware and rescheduled the launch.

The launch was the second to occur from Florida's Space Coast in the past eight days, despite the coronavirus pandemic. On March 18, a SpaceX Falcon 9 rocket ferried another batch of the company's Starlink satellites into orbit, bringing the total up to more than 350.

Related: Atlas V rocket launches US milsat and experimental spacecraft

Meanwhile, most of NASA's Kennedy Space Center is working from home after an employee at the center tested positive for the new coronavirus, SARS-CoV-2, which causes the disease COVID-19.

The virus has wreaked havoc across the globe, overwhelming hospitals and grinding much business activity to a halt. But for now, it's business as usual for the 45th Space Wing and the Eastern Range, which oversees all launch activity at the Cape.

Speaking to reporters on Tuesday (March 24), Brig. Gen. Doug Schiess, commander of the 45th Space Wing, said that the Eastern Range remains ready to support all upcoming launches.

"We're going to continue to do what we do best, which is provide assured access to space, while also taking care of our airmen and their families," he said. "We obviously can't telework launches, so we'll be here working those."

Schiess told reporters that the Pentagon has directed military commanders to continue critical missions, like AEHF-6 and the upcoming launch of a GPS satellite, scheduled for April, while ensuring the health and safety of their teams during the coronavirus pandemic.

"The Department of Defense's priority is to continue the mission, so we'll continue the mission," Schiess said. "I can't see it happening where they would say, 'Stop doing that.' We may do more testing, more temperature testing, or something like that, but I think we have to have a significant population within the operations folks to be sick to have a situation where it would impact our launches."

Related: Coronavirus pandemic: Full space industry coverage

So far, there have been no confirmed cases of the coronavirus at either Patrick Air Force base or Cape Canaveral Air Force Station. Scheiss did say that the base has tests on hand and has administered some of them, but so far all have come back negative.

Scheiss also said that launch teams are taking extra precautions right now. They have reduced staff to essential personnel only and have spread work stations farther apart. Staff are also being monitored for symptoms and encouraged to self-quarantine if they feel sick. Anyone who can telework is encouraged to do so.

According to Scheiss, several hundred people are needed to support a launch, and some missions, like AEHF-6, require more range support than others.

For instance, the launch of a SpaceX Falcon 9 rocket requires around 200 people versus well over 300 people who are needed to support an Atlas V or Delta IV rocket liftoff. These numbers include operators, weather personnel, safety operators and more.

The reason why SpaceX launch teams are a bit leaner is because the Falcon 9 relies on an automated flight termination system, which triggers a self-destruct automatically versus relying on a human to do so.

Public viewing areas near the Air Force Station's entrance are closed during the pandemic, which further cuts back on the number of team members required to support the launch.

Scheiss said that national security payloads will be given priority over other launches, but he doesn't foresee any delays on the horizon beyond the indefinite hold on SpaceX's SAOCOM 1B mission. Slated to launch this month, the mission is on hold due to travel restrictions implemented by Argentina in the wake of the coronavirus outbreak. (Argentina's space agency is the satellite's operator and would need to have representatives on site for the launch.)

According to Scheiss, there is a planned maintenance period scheduled for the beginning of April, where there will be no launches. Following that, launches will resume with a Falcon 9 set to loft another batch of Starlink satellites, and a second will launch an upgraded GPS satellite for the U.S. military. Those two launches are slated for April.

But first, SpaceX (as well as NASA and the military) is looking into an engine anomaly that occurred during the company's launch on March 18. During ascent, one of the Falcon's nine Merlin 1D engines cut out, which led to the booster missing its drone ship landing. This was the fifth flight for this particular Falcon 9 rocket, but SpaceX is being overly cautious and will not launch another rocket until it investigates the anomaly, company founder and CEO Elon Musk has said.

Follow Amy Thompson on Twitter @astrogingersnap. Follow us on Twitter @Spacedotcom or Facebook.

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