U.S. Strengthening Space Domain Awareness

By Yasmin Tadjdeh
Illustration of the Space Fence radar as seen from space.

Space Force illustration

As outer space becomes more congested due to the proliferation of satellites and orbital debris, the Space Force is investing in powerful radars and sensors for better situational awareness.

“Space is a very dynamic domain right now, there’s a lot happening,” said Chief of Space Operations Gen. John Raymond. Just a couple of years ago, the military was tracking 22,000 objects. That number has now risen to 30,000.

“Of those objects, only about 1,500 were actually satellites and everything else was debris,” he said in June during a Council on Foreign Relations event. “If you look now, there are significantly more satellites that are on orbit. In fact, one commercial company has well over 1,600 satellites.”

Additionally, barriers to launch have been reduced and increasingly more and more countries, companies and even students are sending items into space, he noted.

Meanwhile, threats are increasing as well, said Lt. Gen. Nina Armagno, staff director at Space Force headquarters. She cited China’s Shijian 17 — an experimental satellite with a robotic arm that Beijing says will be used to repair spacecraft — as a major concern.

“If you’re going to repair something it needs to be repairable. If it’s going to be refueled it needs to have a fuel port,” she said during a July event hosted by the Mitchell Institute for Aerospace Studies. “This is not the case with their satellites.”

The Space Force views the Shijian 17 as a weapon, she said. Such a system could collide or tamper with a U.S. satellite.

Meanwhile, Russia is also a concern with its Nudol ground-based missile anti-satellite system, she said. There are also worries about a new platform that many are likening to a Russian nesting doll. It’s “a satellite within a satellite within a satellite,” Armagno explained.

The Space Force — which will soon celebrate its second birthday — has and is developing a number of domain awareness tools to increase its visibility into space.

The service is currently pursuing a deep-space advanced radar concept program, also known as DARC. According to the service, the platform is a ground-based radar system designed to detect, track and maintain custody of deep space objects 24/7. It will primarily track objects at geosynchronous-Earth orbit, though it could also track objects in low-Earth orbit, according to officials.

President Joe Biden’s fiscal year 2022 budget request included $123 million for research, development, testing and evaluation for the program.

That’s an increase of about $90 million in funding, said Maj. Gen. James Peccia, deputy assistant secretary of the Air Force for budget, during a briefing with reporters in May.

DARC will augment the military’s space surveillance network as an additional sensor with increased capacity and capability to monitor deep space objects and provide full global coverage, according to budget documents.

The Space Force is pursuing the development of the radar through a middle-tier acquisition process to develop, test and deliver one DARC site. It is projected to be completed in 2025. Additionally, the acquisition approach will provide the foundation for up to two more sites located strategically around the world, according to budget documents.

The Space Force is working with the National Security Technology Accelerator’s Space Enterprise Consortium for DARC. A request for prototype proposals was slated to be released to industry in June but was pushed back to July, according to officials. As of press time, the solicitation had not been released.

The Space Force has hosted four industry days in support of the program over the past several months, said Lt. Col. Kelly Greiner, materiel leader at the Space and Missile Systems Center’s space domain awareness radars division. Since then, the service has been sharing documents and regularly updating companies while also collecting input from industry.

“It’s really a concerted effort on industry’s part, as well as the government, to make sure we get this right and put out a request for prototype proposals that makes sense,” he said during an interview.

There will likely be a “handful” of firms with a mix of primes and nontraditional companies bidding, Greiner said.

“That’s kind of the beauty of going through the Space Enterprise Consortium” where a large number of members are nontraditional firms, he said. That “allows us to get a greater reach into some of those nontraditional companies that we otherwise wouldn’t be able to reach.”

Proposals will be due 45 days after the solicitation is released, likely sometime in the mid-August timeframe, Greiner noted. The Space Force is targeting a contract award by the end of the calendar year. Prototypes will be due in March 2025.

“It’s an ambitious schedule, but it’s doable,” he said. “We’ve had several years to look at this problem set, and we have built out what we call the DARC technology demonstration out at White Sands Missile Range” in New Mexico.

The demonstration facility was constructed over the past two years by Johns Hopkins University’s Applied Physics Laboratory, Greiner said.

Final demonstrations were slated to be completed by the end of July or early August.

“With that coming to a conclusion, we have high confidence in the technology as a whole,” he said. “Now it’s really on the shoulders of industry to go out and build out this first [DARC] site.”

As the effort moves forward, the Space Force is still mulling over where it wants all three of the sites to be located.


“We’re looking at three geographically dispersed sites around the globe, approximately 120 degrees separated for global coverage,” Greiner said. “We are in talks with some partner nations.”

There will be locations within the continental United States, European Command and Indo-Pacific Command regions, he added. Additionally, it would be preferred if they were near the equator, but that is not a requirement.

Meanwhile, Lockheed Martin last year delivered its Space Fence radar to the military. The system — which is based on the Kwajalein Atoll in the Marshall Islands — detects, tracks and measures space objects, primarily in LEO, though it also has visibility into medium-Earth orbit and GEO.

Space Force Maj. Bryan Sanchez, director of operations, cyber and exercises at Space Delta 2 for space domain awareness, said the system has been performing well.

“Due to Space Fence’s sensitivity, we’ve identified over 5,000 new objects for potential inclusion into the space catalog,” he said in an email to National Defense.

Space Fence makes about 130,000 observations per day and can track items as small as 1 to 2 centimeters depending on its orbital regime, Sanchez said.

Later this year, the system’s program office will deliver a “coherent integration upgrade” to the platform, which will enable greater positional accuracy at geostationary orbit, he said.

Sanchez noted that the radar isn’t just tracking space junk.

“While the vast amount of small objects that Space Fence can see is orbital debris, the real value Space Fence is bringing to the Space Force is an enhanced awareness and characterization of the space domain,” he said. “The more objects we can characterize and identify, the greater our freedom of movement through space can be.”

He added: “From ensuring launch providers have a clear picture of the regime they are launching into, to ensuring manned spaceflight safety, … Space Fence helps achieve a more effective and comprehensive space domain awareness.”

According to a Lockheed Martin spokesperson, the ground-based system uses an advanced solid-state S-band phased array radar technology.

“The radar system’s capabilities are a major improvement in the quantity and quality of orbital information to support our national security interests in space,” the spokesperson said. “Beyond cataloging objects, Space Fence will detect closely spaced objects, breakups, maneuvers and launches.”

Meanwhile, as the space domain becomes more contested, the service is moving beyond just seeing what is in space and is actively working to better understand what objects are doing and why, Armagno noted.

However, that requires “a heck of a lot more data,” she said. Previously, information from radars and optical telescopes around the world was coalesced at the Cheyenne Mountain Complex near Colorado Springs, Colorado, where officials cataloged and tracked satellites.

“A lot of the data … was left on the cutting room floor,” she said. “Now we’re putting it into basically a data lake in Colorado Springs, and ... we’re adding information from academia [and] industry. We’re adding data from other countries — because our allies also have space situational awareness capabilities — and trying to create a repository of information.”

Chris Stone, senior fellow for space studies at the Mitchell Institute’s Spacepower Advantage Research Center, said while the deployment of both new and legacy systems has greatly improved the United States’ ability to mitigate gaps in coverage in both LEO and GEO, more work must be done.

“There are still areas that need more coverage such as in the Southern Hemisphere as well as eventually out to cislunar as those requirements emerge,” he said. Cislunar is the region between geosynchronous orbit and the Moon.

Additionally, much of the nation’s legacy radars were designed in the Cold War to counter the Soviet Union, he noted.

“As we progress more into an ever more crowded and contested environment in space, having 24/7 coverage of all orbital regimes is vital to protect and defend our critical space infrastructure and negate surprise on the part of the adversary,” Stone said. “Even with those future systems there are gaps.”

Dean Cheng, a senior research fellow at the Heritage Foundation, noted that visibility into cislunar space will become an area of greater interest soon.

The cislunar domain “is going to become a more intense area of competition,” he said. There are areas there where the Earth and the sun’s gravitational fields cancel each other out, allowing satellites to stay there with minimal amounts of fuel, he added.

“We are putting the James Webb telescope out there, but the Chinese are putting things like data-relaying communication … satellites out there,” he said. “Very different — we’re thinking science. They are thinking practical applications.”

It’s clear that Beijing is pondering what it can do in the vast amount of space that lies beyond GEO. China could have nefarious motives, Cheng said.

For instance, aging satellites that are being retired are sometimes moved into orbits beyond GEO and could one day be used as weapons, he suggested.

“You could imagine, for example, that somebody might put something into a graveyard orbit that isn’t dead, that maybe they could bring it back — either wartime reserve, or even as an ASAT,” he said. “We’re mostly focused on things heading out. What if you had something coming in?”

Topics: Space

Comments (1)

Re: U.S. Strengthening Space Domain Awareness

Very interesting article, it hints that China may have nefarious intents with cis-Lunar space. Tracking things out beyond Geo is very tough!

Charles Phillips at 12:25 AM
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