Lessons from Iraq
The war in Iraq underscored the enormous importance of space systems to the success of U.S. military operations, and the lesson was clear to friend and foe alike. Military space officials are convinced that future adversaries are bent on developing ways and means to neutralize the U.S. space advantage, either by disrupting satellite communications links or by attacking the satellites themselves, electronically or otherwise.

Iraq’s air defense forces have already tried. Throughout Operation Iraqi Freedom, they attempted to jam the signals of U.S. Navstar GPS satellites guiding bombs and missiles to ground targets. The Air Force, having anticipated and war-gamed the jamming attempts, was able to foil them by locating and taking out the jammers with GPS-guided bombs. But Iraq’s use of electronic countermeasures against signals from space was an ominous portent of possibly higher-powered jamming by better-equipped, more adept adversaries in conflicts to come.

As a result, the Air Force is making GPS signals stronger and much harder to jam in other ways as well. GPS antijamming upgrades are among a number of Air Force Space Command programs aimed at ensuring that U.S. forces will be able to operate under the protective umbrella of space superiority.

The Air Force first identified space control, or space superiority, as one of its prime missions and requirements at least 20 years ago, and has been trying to advance the cause, with fluctuating fervor, ever since. But the campaign went largely unheeded until the wars of recent years, dating back to the Persian Gulf War of 1991. That conflict demonstrated both the military value of U.S. space systems and the growing need to protect them.

Congress called for the establishment of a U.S. space control program in 1999. Two years later, the U.S. Space Commission, direly warning of a possible “Pearl Harbor in space,” followed suit. The commission report, which put a premium on space superiority, gave rise to, and is the basis of, Air Force Space Command’s numerous space control programs, officials note.

Expanding situational awareness
Sweeping, all-around situational awareness in space is seen as the foundation of space control. As of now, it is lacking.

The Air Force currently cannot locate and keep track of the all-too-numerous objects in space, and thus is limited in its knowledge of what is going on there. The service has therefore set its sights on identifying and determining the positions of all operative and inoperative satellites, as well as all orbiting debris, and on knowing who is operating which satellites and why.

“Our near-term focus on space control is to greatly improve our space situational awareness,” explains Peter B. Teets, undersecretary of the Air Force and director of the National Reconnaissance Office. “We don’t have as much knowledge of what is happening in space as we would like to have. It might be hard for us to know if we were under attack by an adversary.” Thus the first order of business is “knowing whether we are” under attack, the undersecretary asserts.

Every now and then, U.S. satellites encounter electromagnetic interference in space that makes their on-board computers malfunction. Teets says such incidents are most likely caused by natural phenomena, but acknowledges that this is uncertain. “So we just scratch our heads and reboot the computers,” he says.

To dispel doubts about the sources of such interference, the Air Force has embarked on several surveillance-enhancement projects overseen by Air Force Space Command’s directorate of space control requirements. In a starring role among them is the Space Based Space Surveillance System (SBSS) program conducted by the Air Force Space and Missile Systems Center at Los Angeles AFB, Calif.

	The Space Based Space Surveillance System is expected to become the cornerstone of the space surveillance network.

SBSS, a constellation of satellites using electrooptical sensors, is expected to become the cornerstone of the space surveillance network, augmenting and greatly improving on the network’s long-standing ground-based space surveillance systems.

The first SBSS satellite contract was scheduled to be awarded late this year. The SBSS constellation could consist of four to eight satellites, with the final number to be determined on the basis of additional analysis, officials say. The Air Force intends to upgrade successive SBSS satellites as required by changing circumstances, and as warranted by emerging technologies.

The Air Force planned to put the constellation’s first spacecraft—the SBSS Operational Pathfinder satellite—under contract late last year. That satellite had been penciled in for launch in 2008, but the Air Force decided to expedite its production and have it ready to fly in 2006 instead.

The big picture
Dickman explains that the service wants to attain the same high level of situational awareness in space that the airborne warning and control system (AWACS) provides in the air. Just as the broad-area radar on an AWACS aircraft shows the big picture in the air, the sensors on SBSS satellites will do the same in space, he says.

The whole idea of SBSS is to keep a much closer watch on space from space itself. Space-based sensors should be able to see what is in space, and what is going on there, much more clearly than earthbound sensors can. The Air Force especially wants to get a clearer view of objects in deep space orbit, and the first SBSS satellite should provide this, officials say. That satellite should be capable of covering objects in LEO as well. The full constellation will have everything covered, planners claim.

Spacecraft that change orbits are high on the Air Force’s “must-see” list.

“We want to know where everything in space is, where it’s going, what it’s doing, and whether it’s doing anything different from what it was doing before,” Dickman explains. “We especially want to know if it can maneuver. If it can, it’s an operational spacecraft. And the reason it’s maneuvering is to change its mission—it wants to look at something at a different time, or listen to something or send a signal at a different time.

“We’ve got to have the surveillance to know if something is coming to attack us, so we can defend. Or if the time comes when we’re going to attack somebody else in space, from the ground or anywhere else, we’ve got to know exactly where they are,” says Dickman.

Upgrading the network
The existing USAF space surveillance network (SSN) cannot provide the comprehensive space coverage that has become essential. Operated by Air Force Space Command, SSN consists almost exclusively of Cold War-vintage mechanical-tracker radars, phased-array radars, and electrooptical sensors at 25 sites in the U.S. and elsewhere. Many were originally designed to detect ballistic missiles headed for North America.

SSN’s land-based electrooptical sensors are hindered by cloud cover, and its radars are limited by their geographic locations.

A key element of SSN is the ground-based, electrooptical deep space surveillance system (GEODSS), a network of three telescopes linked to video cameras trained on, and looking for movement in, star fields. In place since the early 1970s, GEODSS is undergoing an upgrade that will add charge-coupled devices to its sensors. This will make the system more flexible in its tracking as well as more sensitive in its observations, officials say.

SSN also contains the naval space surveillance system, known as the “Navy fence,” a network of continuous-wave radars positioned across the southern U.S. Deployed more than 40 years ago to keep the fleet informed of the whereabouts and approaches of Soviet spy satellites, the Navy fence consists of three transmitter sites, six receiver sites, and a computational center.

Ownership of the naval surveillance system was recently transferred to the Air Force, which will shortly decide whether to upgrade it, replace it, or keep it as is. One possibility, officials say, is to change its frequency from UHF to the higher S-band, thereby enabling it to identify, keep track of, and record many more thousands of much smaller objects in space.

	Only one sensor remains functional on the MSX spacecraft.

SSN is currently capable of detecting, tracking, and cataloguing man-made objects such as active and inactive satellites, spent rocket bodies, and space debris (including, at one time, the discarded glove of a Gemini astronaut). Some of these objects are as small as 10 cm in diameter, or the size of a baseball. Upgrading the Navy fence would enable the surveillance network to spot objects one-fifth this size, and thus to “meet a lot of our needs and NASA’s needs,” notes an Air Force official.

In monitoring space, SSN employs a so-called “predictive” technique, spot-checking objects as they enter and reenter certain sectors, rather than tracking them continuously in orbit. The SBSS constellation should broaden the scope and expand the sweep of SSN. Even though the ground-based surveillance systems cannot provide enough information to enable the Air Force to see and comprehend what adversaries or potential adversaries are up to in space, they are considered invaluable, and will remain in service after the SBSS constellation is up and running.

“There is always going to be a place for the ground-based systems, because they are cost effective,” notes Col. Susan Helms, Air Force Space Command’s division chief for space control requirements. “But space control has to be space-centric. We need to go to space in order to be vigilant there and fully understand what is happening there. We’re zeroing in on the types of capabilities we need for that. We need to get the sensors away from the constraints of the atmosphere.”

	GEODSS is a key element of the space serveillance network.

SSN includes only one spaceborne sensor, which it acquired quite by chance. Called the space-based visible (SBV) sensor, it was carried into orbit aboard the midcourse space experiment (MSX) satellite that the Ballistic Missile Defense Organization launched in 1996. Of the several visible, ultraviolet, infrared, and spectrographic sensors on the large MSX spacecraft, only SBV is still in operation.

BMDO wanted to find out whether and how well the MSX sensors, including SBV, could spot ballistic missile rocket bodies vaulting into space. It quickly became apparent to the Air Force that SBV does a fine job of tracking bodies in space as well.

“It’s been a great sensor for us,” Dickman declares. “It feeds into our [space] catalogue all the time. We hope SBV will last three more years,” or until the first SBSS satellite begins operating in space.

Space RAIDRS
New programs and techniques for protecting and defending space systems also are featured in the Air Force’s pursuit of space control capabilities. A prime example is the rapid attack, identification, detection, and reporting system (RAIDRS), a so-called defensive counterspace program.

“RAIDRS,” Dickman explains, “is a program for putting specific things—a series of sensors—on spacecraft to detect whether they are being jammed, or irradiated, or attacked by hit-to-kill weapons, or whatever, and to pass that information to the ground.”

Helms says RAIDRS will constitute “the nervous system of our space forces, giving us a comprehensive understanding” of the nature of attacks on U.S. satellites. The first software elements of the computer-oriented program are scheduled to be incorporated in satellite ground-control stations in 2008. This should make the ground controllers better able to manipulate and interpret data downloaded from satellites, and to determine, for example, whether the satellites are being buffeted by space “weather” or are being attacked.

RAIDRS software will be incorporated into future satellites prior to their launch, and will be installed in the black boxes of those already on orbit by means of programming instructions from computers on land.

The Air Force also is developing new offensive counterspace systems to counterattack the antisatellite (ASAT) weapons and counteract the ASAT capabilities of hostile forces. Prominent among these developments are the counter communications system, designed to jam the space-based communications used by an enemy for command and control, and the counter surveillance and reconnaissance system, designed to do basically the same thing against space-based surveillance and reconnaissance systems that look down on, and target, U.S. forces. The former is scheduled for initial delivery to the Air Force this year; the latter is expected to go into service in four or five years.

	The MILSTAR satellite network provides vital military communications links.

Details of the programs are classified, but the concepts are not. For example, the Air Force can be expected to “do things to try to spoof the radars” of enemy radar satellites “to get them off track,” as one official puts it. Another possibility: shining bright lights on hostile imaging satellites to blind their optical sensors.

All U.S. offensive counterspace systems are designed to be nondestructive—to cause temporary, reversible disruption, with no permanent damage. “We want to take down the capability but leave it able to come back up,” Dickman explains.

Combat space vehicles?
At some point, many space officials believe, the U.S. must build manned or unmanned fighting machines—combat spacecraft—that could be launched on short notice to defend U.S. satellites and to provide assured access to space. As envisioned by some planners, such machines would be designed to intercept hostile spacecraft and also, perhaps, to attack the enemy in the air and on land as well as in space.

Consistent with treaty obligations, U.S. policy now permits the development and operation of space control capabilities to ensure freedom of action in space, and, if necessary, to deny it to adversaries. This is widely interpreted as paving the way for the eventual deployment of space-control spacecraft.

The Air Force and NASA are teamed in an analysis of possible future space vehicles—manned and unmanned—to provide quick and sure access to space, and to service and repair satellites, among other things. The Air Force is also working with DARPA on concepts for “an operationally responsive launch vehicle that can do satellite placement or anything else it would need to do,” Dickman says.

The Air Force has had a long-standing “operational requirement for an operationally responsive space system—an orbital spaceplane, a space maneuver vehicle, or you name it,” notes Dickman.

He notes that the Air Force has “a number of technology programs in place to think through how to protect our space systems physically, from space, from the ground, or from wherever we have to do it. We’re in the space superiority business. If we weren’t thinking about how to defend ourselves actively against somebody trying to do us harm, we’d be foolish.”