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How Air Force Space Aggressors Protect Our Satellites—And Way Of Life

Twenty miles east of Colorado Springs, in the middle of sagebrush and ranchland, two small Air Force units train the U.S. military for the growing battle over space.


About an hour after the sun disappears behind the Front Range on a cold February evening, Lieutenant Colonel Anibal Rodriguez steps outside a two-story warehouse on Schriever Air Force Base, east of Colorado Springs. From where he stands, Rodriguez can see the city’s light pollution, an ethereal purple-pink glow, casting the Rockies in a different kind of purple mountain majesty. It’s a clear evening, and despite the far-off light, a million twinkling stars begin to emerge. Rodriguez cranes his neck and looks up at the sky.
If he stands here all night, he can watch those constellations born from Greek mythology—first Taurus, then Orion, and later Leo—move across the sky. But it’s the stars that don’t move and don’t twinkle that have captured Rodriguez’s interest this evening. Those stationary celestial bodies aren’t stars at all, but rather communication satellites parked thousands of miles above the Earth, rotating in lockstep with the planet. Some of them are transmitting episodes of Homeland. Others are providing a constant channel for communications between the men and women of America’s military. Tonight, those satellites have targets on their solar-paneled backs.
There’s a rich irony in the fact that the heart of modern American warfare sits in the middle of cow pastures, juniper trees, and sagebrush on Colorado’s plains. The directions to Schriever Air Force Base—home of the newly minted National Space Defense Center—come with instructions to keep an eye out for deer and antelope as you pass gravel roads with names like Paddock Road and Quail Drive.

Perched on a rise 20 empty miles from Colorado’s second-largest town, the base’s view is awe-inspiring: You can see Pikes Peak and the gneiss and granite fingers of the Sangre de Cristos stretching southward. Contrails crisscross the vast sky above Schriever—and yet this base of more than 9,000 airmen has no runways. Schriever’s domain is well above the clouds: This is the home of the 50th Space Wing, whose mission is to “evolve space and cyberspace warfighting superiority through integrated and innovative operations.” Part of that evolution falls to a group of less than 100 men and women who are known as Space Aggressors.

Although the Space Aggressors are located at Schriever, they technically belong to the 57th Adversary Tactics Group and the 926th Operations Group. Made up of one active-duty squadron (the 527th) and one reserve unit (the 26th), the Space Aggressors’ mission is to train American troops in the art of fighting without the aid of modern space-based tools such as the Global Positioning System (GPS) and satellite phones. They aren’t riding missile-equipped spaceships into our outer atmosphere like science fiction space cowboys. Instead, they’re helping the U.S. military detect and discern when things like GPS and satellite communication signals are being intentionally disrupted or corrupted—and teaching troops how to function without them. Their domain is approximately 73 trillion cubic miles of dynamic atmosphere—a playing field that extends from Earth to satellites sitting 40,000 miles above the planet.

Instead of tanks and machine guns, the Aggressors’ weapons cache includes modems, oversized antennas, and radio frequency equipment. It’s gear that can largely be purchased on Amazon (“There’s nothing Gucci about this stuff,” says Rodriguez, commander of the 527th) but which has a reach far greater than that of any bullet. After all, the signals that those tools, coupled with other technologies, can disrupt are the same ones troops tap to communicate with one another, to relay images and other data, and for early missile detection signals—and that DirecTV uses to bring you Game of Thrones. And while fighter jets, drones,
and smart bombs use GPS signals, in part, to navigate, the civilian world relies on them for everything from transportation to banking. There are, in fact, very few things in the military and civilian world that do not rely on information relayed through our satellite systems.
Which is why the Aggressors are such an integral part of the Air Force’s Space Operations—and the military at large. As the only units of their kind in the U.S. military, Schriever’s Space Aggressors play war with the Air Force and the likes of Navy SEALs, Army soldiers, and Marines. They’re the sparring partner for the entire Department of Defense—in effect, permanent bad guys. And for them, losing often means winning. “The job we do in terms of training is to ensure that our guys are able to get the job done right and come back safe,” Rodriguez says. “But if you step back even further, if we don’t get this right, what is at stake is the way of life we’ve all reaped the benefits of for the better part of the 21st century.”

As the sun began to light up Eastern China on January 12, 2007, the Chinese weather satellite known as Feng Yun 1C, or “wind cloud,” was cruising along its orbit 500 miles above the nation. Although still emitting an electronic signal, the satellite was eight years old and ready for retirement. It got its send-off later that day, courtesy of a Chinese anti-satellite missile that collided with Feng Yun 1C and obliterated it into thousands of pieces of debris—fragments that now have to be tracked along with the 23,000 other pieces of space junk floating around our planet. Even something as small as a paint chip, when traveling at 17,000 miles per hour, can wreck a satellite or other important space objects like, for example, the International Space Station. That’s why both NASA and the Air Force track everything, from astronaut gloves to broken satellite wings, that is whirling around our world.

The 2007 intentional satellite smashing was the first time the Chinese had demonstrated an ability to threaten U.S. space assets—and it rattled the American military. Up until that point, it had been fixated largely on the potential capabilities of our longtime space rival: Russia. “The number of countries seeking to develop capabilities to compete militarily with the United States in the space domain on a peer-to-peer level,” Rodriguez says, “has gone from one to…more than one.”

Several countries, Russia and China among them, are reported to have the ability to launch anti-satellite missiles. And despite Hollywood’s suggestion that moving satellites is as easy as resetting your sprinklers, it’s not a quick and painless process. Depending on its type, a satellite might not be in constant communication with the ground. Beyond that, it takes fuel to maneuver in space—fuel that’s supposed to be used to carry out the satellite’s mission. If you burn all of the fuel, you’ve almost done an adversary’s job for them. China has continued to test deep space weapons, reportedly firing a missile to a distance that would be capable of hitting some of the United States’ farthest flung—and most valuable—satellites in 2013. (China denies testing such a weapon and says it is developing tools for only peaceful uses in space.) North Korea, Iran, and Russia, among others, have also demonstrated potential satellite-killing technology.
But attempting to blast satellites out of the sky falls into the cutting-off-your-nose-to-spite-your-face category. Smashing satellites with missiles would create a debris field so massive and dangerous it would essentially render space exploration and satellite function impossible for everyone for decades to come—so nobody would be able to use space. Like nuclear war, it’s a lose-lose situation.
So more insidious technologies have been born. Russia has recently launched satellites with the ability to cozy up next to, listen to, observe, and (some have suggested) even grab on to other satellites. China and Russia both have been developing lasers that have the ability to “blind” satellites by damaging their imaging sensors. (The United States, for its part, has acknowledged the development of similar technologies but hasn’t divulged just what, exactly, it’s got up in the great beyond.) Perhaps the most
concerning technique—one Russia has allegedly already put to use in the Baltics—is GPS “spoofing,” or the ability to mimic or modify a GPS signal to confuse or misdirect an enemy.

For GPS to determine a precise location, the receiver on the ground must receive signals from at least four different GPS satellites. An enemy spoofing a fake signal, though, can throw off the calculation and, thus, the receiver’s ability to gauge an accurate location. It’s not that difficult to do: Because GPS has largely evolved with commerce—not covert ops—in mind, its frequencies are readily available to anyone with a keyboard and decent ability to use Google. For example, in June 2017, a commercial ship in the Black Sea, near a Russian port, reported a GPS location that couldn’t possibly be right: The ship’s own GPS pegged it as sitting at an airport about 25 miles from its actual location. More than 20 other nearby ships all confirmed that their GPS, too, registered them as sitting aground at the airport. (Russia denied allegations of misdirection.) While the error might not have caused any issues for the ships in that instance, imagine a smart bomb or drone being nearly 25 miles off the mark.
The incident came a month after director of national intelligence Daniel R. Coats noted, in a May 2017 report for the Senate Select Committee on Intelligence, that the global threat of electronic warfare against space systems will only expand in the coming years. In his report, Coats cites specific concerns about foes jamming military satellite communications, imaging satellites, and Global Navigation Satellite Systems (GNSS) like GPS. To that end, the nonprofit Resilient Navigation and Timing Foundation’s 2016 white paper about threats to GPS identified terrorist and military jamming as among the most significant. It’s a problem complicated by the fact that the same tools China, Russia, and others might develop for peaceful purposes could also be used for sinister ones. That’s where the Space Aggressors come in.

Rodriguez’s stargazing platform is also part of the Space Aggressors’ home, a two-story warehouse dubbed “the Barn.” It gets its name from the fact that the systems the Aggressors use to simulate enemy attacks on satellite signals once were given animal names, and since you keep animals in a barn—well, you get the connection.

Most airmen who join the Space Aggressors squadron have some previous experience in space operations. Few people—enlisted or officers—come straight out of their initial military training. For example, Lieutenant Colonel Laura Kohake, commander of the 26th reserve unit, joined the Space Aggressors after an inaugural stint with the 7th Space Operations Squadron, the Schriever group responsible for operating an infrared imaging satellite. “I showed up there and I didn’t even know what the parts of a satellite were,” she says. “I learned as much as I possibly could as fast as humanly possible because I was supposed to be the technical expert.” Once airmen join the Space Aggressors, they go through several weeks of training before they’re ready to take part in missions. Today, Kohake can detail not only the many complicated parts of a satellite, but also explain the orbits in which they live and why. She’s the rare kind of technician who can break down the science for the uninitiated.

Kohake isn’t at the Barn tonight, but many of her experienced reservists are. A handful of them are gathered around the Barn’s bar, perhaps one of the last informal bars on Schriever Air Force Base. Some scoop popcorn out of the movie-theater-style machine behind it. There’s no booze this evening, though; the Aggressors gathered in the Barn are taking part in a large-scale Air Force mock battle known as Red Flag.

Throughout the year, the Air Force carries out several weekslong Red Flag exercises. The series of simulated battles largely take place at the Nevada Test and Training Range at Nellis Air Force Base. Often the United States invites its most trusted allies to take part in what it calls its Super Bowl. Because air—and land and sea—combatants rely heavily on space-based assets, the Space Aggressors play an important role in the event. Tonight, the Aggressors in the Barn will work to jam, disrupt, and distort satellite
communications—using tactics U.S. intelligence analysts have determined our adversaries are likely to try—to confuse the American forces, their “training audience,” 820 miles away in Nevada. “Hopefully we lose tonight,” Rodriguez says. “When we lose, America wins.”
When he’s not answering to “Lieutenant Colonel Rodriguez” or “Sir,” Anibal Rodriguez also goes by “Slowpoke,” a nickname he earned during his advanced weapons training. It’s a funny moniker for someone who, as a young man growing up in Florida, wanted only to be a test pilot flying faster than the speed of sound. “I knew I needed a technical degree to do that and that Embry-Riddle [Aeronautical University] had one of the largest Air Force ROTC detachments outside of the Air Force Academy,” Rodriguez says. So he enrolled in the university’s aerospace engineering program, where he admits he struggled initially. Little wonder. Embry-Riddle has one of the most challenging aerospace curricula in the country and one of the highest tuitions, a cost Rodriguez was footing himself. As a noncitizen—he’d moved to Florida from Bogotá, Colombia, when he was a teen—he wasn’t eligible for ROTC scholarship money.

By his junior year at Embry-Riddle, Rodriguez had earned his citizenship and was close to completing the degree that would help him take the first steps toward the cockpit. Then, in his final months as a student, his nearly 20/20 vision deteriorated—and with it, his dreams of becoming a pilot. He searched for a new career path, and the Air Force gave him a choice: intelligence or space and missiles. “I had no idea the Air Force even did anything in space, but I thought, At least it’s operationally relevant,” Rodriguez says. About a year after graduation, he was sent to Montana where he spent four-and-a-half years in an underground silo, watching over intercontinental ballistic missiles. At the end of his tour, he moved above ground into space operations in Colorado. “I’d joined the military to see the world,” Rodriguez says, “and I’d just spent about five years stuck underground.”


Shipping Lanes in Space: Many satellites follow either a low medium, or geostationary Earth orbit. GPS satellites can be found in MERO, while many communication satellites exist in GEO. Infographic by Sean Parsons.

In January 2008, he landed at Schriever, which—together with nearby Peterson Air Force Base—plays an important role in the Air Force’s space operations. As the headquarters of Air Force Space Command, Peterson is home not only to the units that track deep space objects, but also those tasked with providing detection and warnings about ballistic missiles as well as electromagnetic interference. Thirteen miles up the road, Schriever’s units are responsible for operating and protecting many of the United States’ deep space communication satellites and the constellation of around 30 satellites that provide GPS to the entire country—including to your smartphone. It was at Schriever that Rodriguez first realized how fragile and vulnerable GPS, the underpinning of much of modern American infrastructure, was.

“It’s not just about the military,” he says. “In some ways, with GPS, what’s at stake is a national treasure.”

The U.S. military launched its first GPS satellite in 1978. The third generation of GPS satellites are set to begin launching later this year and will improve GPS accuracy from about 20 feet to about two. The Air Force opened the network fully to the public for free in 2000, and today, American society leans heavily upon GPS, which does a lot more than just get you from Wash Park to LoHi. Everything from the stock market to banking to the power grid is dependent, in some way, upon GPS because of its precise timing capabilities. In fact, despite the “positioning” part of the moniker, GPS’ timing function is arguably the system’s more essential use. Understanding why requires a rudimentary comprehension of how GPS—and satellite orbits in general—work.

The satellites that make up America’s GPS orbit roughly 12,000 miles above the Earth, lapping the planet once every 12 hours in what’s called a medium Earth orbit, or MEO. This distance gives the satellites the ability to view a larger swath of the planet than the lower Earth orbit (LEO, between about 100 and 1,200 miles above the ground). There’s also geostationary Earth orbit (GEO), around 20,000 to 40,000 miles above the Earth, and the highly elliptical polar orbit known as Molniya, in which satellites essentially slingshot around the poles, going slower over the North Pole before whipping around the southern one. These different orbits are like shipping lanes in space, where satellites with different purposes travel. After all, there are more than 3,000 satellites orbiting Earth right now, the majority of which are operated by private groups, not nations. Weather and other imagery satellites typically hang out in LEO, where they go around the Earth every 90 to 130 minutes; GNSS’ domain is usually in MEO; and way out in GEO, you’ll find mostly communication satellites, including those for military users and also commercial units for companies like Sirius XM and DirecTV. The reason for this is that satellites in GEO move at the same rate as the Earth, so those satellites are always looking at the same place on the ground. That ensures DirecTV has the ability to broadcast to the same audience, and it also allows the U.S. military to have a reliable channel over which to communicate and share data.

Think of GPS satellites in MEO like buoys in space, constantly sending out signals that include the devices’ times and positions. Thousands of miles below, receivers, like your smartphone, pick up the signals and determine precise locations by using the information—and differences in the time that information comes in—from each satellite. To ensure this exactness, each GPS satellite is equipped with super-precise atomic clocks. The United States Naval Observatory uses those timing systems to provide Coordinated Universal Time (UTC), the standard America uses for everything from stock market transactions to electrical power grid management to transmitting police and other emergency services communications. Why is a timing standard so important? Because those complex systems pass data across networks that all have to be synchronized. “Those networks don’t send long messages to each other,” says Dana A. Goward, president of the Resilient Navigation and Timing Foundation and a member of President Donald Trump’s National
Space-Based Position, Navigation, and Timing Advisory Board. “They send strings of data, and they have to all know exactly what time it is so they can time-stamp the little packages of data and make sense of them.”

Should GPS go offline for a period of time, those systems—cell towers, ATMs, electrical grids—become dependent upon their own built-in backup clocks, some of which are good, some of which are not so good, and some of which are nonexistent. The longer GPS is off the mark in terms of timing, the less synchronized these complex systems become, a phenomenon known as “clock drift.” Essentially, the traffic cops for our digital world could lose the ability to talk to one another. Should that happen, all modes of transportation could slow down, Goward cautions, noting that everything from traffic signals to airplanes to shipping ports relies on the timing function of GPS. There could be power outages. ATMs could become inaccessible. Cell service could become spotty. It doesn’t take a lot of imagination to see the dark path down which the loss of that technology and human nature could take us. In fact, a couple of years ago, we got an early glimpse.

Attendees of the Institute of Navigation’s Precise Time and Time Interval annual meeting in 2016 were just finishing up their first day of discussions in Monterey, California, on January 25 when the Boulder contingent’s cell phones started going off. These representatives from the National Institute of Standard and Time (NIST) were connected to a national alarm system set to send near-constant text alerts when UTC had run amok. Beginning at 5:10 p.m. Pacific Standard Time, the NIST staff members’ cell phones squawked, beeped, hooted, and buzzed every 10 minutes with alarm messages. Something was wrong.

Things had started to go askew hours before at Schriever Air Force Base, where, at 4 p.m., the 2nd Space Operations Squadron (2SOPS) team—the small group in charge of operating the country’s GPS constellation—had taken one of its oldest satellites out of service. It was a planned decommissioning: Space Vehicle 23 had been launched in 1990, the first in a group of 19 just like it. But when the 2SOPS team pulled the satellite’s proverbial plug, a system glitch resulted in a timing error of 13.7 millionths of a second—about the time it takes for a hummingbird to beat its wings once—in roughly half of the United States’ GPS satellites.

The timing malfunction lasted just a few hours before it was recognized and addressed, but it took more than a day in some places to restore the systems affected by the 13.7-microsecond hiccup. Cell phone companies experienced service interruptions; first responder networks across the nation reported faults; and in Puerto Rico, the Arecibo Observatory—one of the world’s largest radio telescopes, which, among other things, tracks asteroids on potential collision courses with Earth—shut down for at least part of a day. None of these disruptions qualified as critical failures, though, and in some ways, that was comforting. The short-term glitch had jarred some U.S. infrastructure, but the world hadn’t ended. Then again, the NIST team had recognized the error and the Air Force had corrected it within hours. What happens if GPS fails for longer than that?

“We’re not really sure, because the systems that rely on it are so complex,” Goward says. Although the National Security Telecommunications Advisory Committee has suggested that the United States has enough backup systems in place to mitigate the effects of clock drift from prolonged GPS outages for approximately 30 days, other agencies aren’t so confident. The Department of Homeland Security itself has called GPS “a single point of failure for critical infrastructure.” And that’s precisely why some U.S. adversaries have targeted it.

When the Trump administration revealed its 2019 budget request for the Department of Defense, the Air Force’s proposed unclassified space budget got a lot fatter: around eight percent bigger, or about $8 billion more. That’s because, in part, as Air Force budget director Major General John Pletcher noted to reporters at a February Pentagon briefing, “We are in a more dangerous security environment than we have seen in generations. Global trends are eroding our advantage in air and space.”

In the case of space, at least, it seems fair to interpret “global trends” as largely Russia and China, both of which have built up their space capabilities in recent years. Like the United States, Russia has its own GNSS constellation, GLONASS. China’s system (BeiDou)—as well as Europe’s (Galileo)—are already functioning regionally and should be fully operational by 2020. But many of our adversaries are less concerned than we are about having to operate without GNSS because they have backup systems: Russia has a terrestrial position, navigation, and timing system called Chayka, Russian for “sea gull,” that will allow the country to maintain precise timing and positioning in the event of a GNSS disruption. China and Iran have similar systems. So do South Korea and Saudi Arabia. We don’t.

The United States recognized its GPS vulnerability in the early 2000s, and President George W. Bush issued a security directive calling for the development of a backup system. An executive committee, co-chaired by the secretary of transportation and the secretary of defense, was assigned to find a plausible solution for our reliance on GPS’ clock. It did—in a World War II–era radio broadcast system known as LORAN (long-range navigation). Without getting too technical, the LORAN and, later, LORAN-C systems, which were in use until 2010, broadcast low-frequency radio signals—at the opposite end of the spectrum that satellites use—across a network of towers. Those signals can be used for both navigation and timing. The proposed enhanced LORAN system (eLORAN) would offer a signal that is terrestrially based and much stronger than GPS—and much more difficult to jam, too.

So why, 14 years later, don’t we have this system? The short answer: funding and bureaucracy. The small amount of money allocated to put the eLORAN system into play was nixed in a succession of budget cuts that began with the administration of President Barack Obama. “The policy never changed,” Goward says, noting that Obama also supported the development of the eLORAN system. “The solution everyone had agreed upon was defunded.” That could be changing. The National Defense Authorization Act passed in 2017 mandated that the federal government create a small-scale eLORAN demonstration project as an initial step toward a full-scale system, which Goward estimates could cost about $500 million. An additional challenge, as Goward sees it, is that no one federal agency is responsible for GPS. “The Air Force is responsible for broadcasting the signal, yes,” Goward says, “but its responsibility ends when the signal leaves the satellite.”

The Air Force also has more than just GPS fish to fry. While the 2019 budget adds $452 million for additional GPS satellites, another big bump—$643 million—comes in spending on research and design for our missile-warning system and other space systems. That reflects changing threats. It’s not just about disrupting signals, Rodriguez says. It’s about real threats actually in the space domain. In fact, there have even been recent suggestions to establish a new armed forces branch: the Space Corps. “Our adversaries are developing capabilities to hold assets at risk in a physical sense,” Rodriguez says. “We’re talking about things like directed energy—lasers. Or simply getting a little too close to another satellite in GEO.”

Think about the geostationary Earth orbit—in many ways, the most coveted orbit, because it allows satellites to stay in line with specific locations—like a big line of parking spaces. The International Telecommunication Union, a U.N. agency, works to assign every satellite a particular parking spot. If a satellite gets too close to another’s assigned parking space—intentionally or not—it can prevent the satellite assigned to that area from operating, just like if another car is too close, you can’t open your door.
Other than those assigned parking slots, when it comes to space, there is no agreed-upon rulebook in terms of how to behave, unlike on air and land and sea. “In all other domains we have years of experience in terms of policy, international law that dictates the rules and sets of actions that can and cannot be taken—what is considered hostile and what is not,” Rodriguez says. “In space, we don’t have those data points to inform our actions, to characterize whether something is of a hostile nature.” Currently, the only binding agreement about the use of space is a 1960s-era U.N. document on the peaceful uses of outer space. But scholars at McGill University’s Centre for Research in Air and Space Law and a team of subject-matter experts are working to develop a manual for how international law applies to military uses of outer space. “We’re writing the book on space as we speak,” Rodriguez jokes.

Not having a rulebook certainly doesn’t make the Space Aggressors’ jobs any easier. Neither does the demand for their services: In the past few years, the Space Aggressors have seen a significant increase in requests for their training. “Right now, the need for what the squadron is doing is growing at a pace that our resources cannot keep up with,” Rodriguez says.

Perhaps fittingly, the night of the Aggressors’ Red Flag mission coincides with February’s brief government shutdown. And yet, the Space Aggressors are still gathered in the Barn, many of them reservists like Lieutenant Colonel Jaska Cason, a former C-130 cargo plane pilot. Around 8 p.m. he leads a walk-through of the evening’s mission. The airmen practice adjusting radio frequencies, demonstrating just how they can disrupt the signals, and citing patterns called “hoppers” and “sweepers” that look like colorful Etch A Sketch drawings on the display. Rodriguez stands on the periphery. He’d flown in from Nellis in Nevada earlier in the day and has only had a few hours of sleep. He drinks coffee and listens to a senior airman explain that they want to challenge their training audience, but they don’t want to dominate them tonight. They could if they wanted to, but they won’t. “That would defeat the point of the training,” Cason says. “It’d be like you boxing with Muhammad Ali. What are you really going to learn?”

Rodriguez smiles. He looks a little tired, but happy. This is one of his last Red Flag exercises as commander of the 527th Space Aggressors. In June, he’ll hand over command of the squadron to someone else and move into a new job at Peterson. He’s sad to leave, he says, but that’s the way of the military: always moving, always changing. The same is true for the Space Aggressors. They’ll keep learning, keep growing, keep training as the threats around the world move and change, carrying out a mission almost as infinite as the stars that light up the sky over Schriever each night.


Kasey Cordell is 5280's features editor.

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