Bold move escalates space war debate

James Oberg NBC News space analyst

One week ago, a major “space first” occurred high over west central China — and in total darkness. No fiery explosion or glowing clouds would have been seen. But an aging Chinese satellite was instantaneously converted into a 542-mile-high cloud of metallic confetti.

As first reported in Aviation Week and Space Technology, and confirmed a few hours later by National Security Council spokesman Gordon Johndroe, U.S. intelligence agencies believe that China launched a medium-range military missile from its Xichang spaceport and guided it into a high-speed, head-on collision with a weather satellite called Fengyun-1C.

For the first known time in history, a missile launched from the ground destroyed an orbiting satellite. The event is supposed to have occurred about 5:30 p.m. ET on Jan. 11, or 6:30 a.m. Beijing time Jan. 12.

Previous anti-satellite weapons tests, conducted during the Cold War, involved either co-orbiting killer satellites (the Soviet approach) or an air-launched anti-satellite missile (the U.S. approach, also considered by the Soviets but never attempted). Some tests involved shooting ground-based anti-missile missiles toward satellites, but those missiles never hit their mark. And a NASA flub of a robot rendezvous in 2004 resulted in the active satellite accidentally hitting — but not damaging — its target satellite.

Extraordinary chain of events
Many of the details surrounding last week's event are classified — but even the unclassified information confirms that something extraordinary occurred.

The North American Aerospace Defense Command, or NORAD, routinely releases reports on the orbits of hundreds of satellites of interest. Fengyun was the subject of about one or two reports per day throughout 2006, going into early January. But there were three reports on Jan. 10, then five reports on Jan. 11. And there have been no reports on Fengyun-1C since the time of the reported disintegration.

Rumors of an “energetic breakup” started circulating last weekend. A spokesman for the U.S. Strategic Command reported having no information about the breakup — but considering the hundreds of different pieces that are probably now being tracked, it can take a week or more to make sense of the radar returns.

Evidence of an actual missile launch would require tracking data from infrared observation satellites operated by the Pentagon. While that information would be highly classified, the obvious confidence among officials promoting this interpretation implies that they do, in fact, possess that sort of evidence.

It remains remotely possible that Fengyun blew up on its own, as many satellites and derelict rockets do when leftover fuel eventually mixes and ignites. But according to an expert who talked privately with MSNBC.com, the satellite “had little or no prop[ellant]; the only internal energy source might be batteries, which don't have that much energy. So it would be easy to rule out internal causes.”

Fengyun's loss also could be due to a massive meteoroid or orbital debris hit, occurring coincidentally within range of China’s main space launch base. But the odds of that are even smaller.

How big — and how high — a threat?
Why Fengyun became such an object of interest to U.S. military intelligence agencies in the days before the missile launch remains intriguing — and possibly of critical importance. Perhaps the retired satellite had been reactivated, and observers recognized this as an omen of the impending fireworks.

The last orbital data released by NORAD seem to show one end of the satellite's orbit being raised by about 20 miles (32 kilometers). Such tweaking is characteristic of a satellite lining up its orbital path for a rendezvous with a ground-launched visitor. The international space station does this in preparation for Russian spacecraft visits.

In fact, the reason the U.S. Air Force chose the air-launched anti-satellite system is that it does not have to have its target line up with a ground-based missile pad. Naturally, a real target in the real world would never make such a helpful maneuver.

Without the target’s maneuver to make itself easier to kill, a ground-based shot would likely have to be made from the side — or “out of plane,” in space navigation parlance. With such a geometry, the final approach for physical contact occurs under much higher rates of angular change, making terminal guidance much more difficult. It can be done, but with less reliability.

The geometry of this particular test (and also, whether this test was the first shot, or the fourth or fifth or more) remains classified. But further leaks and revelations can be expected.

How to avoid a space bullet
Also to be expected are suggested schemes for countermeasures. First of all, space is not under a uniform hazard from ground-based weapons. The higher you are, the less threatened you are. This is partly a matter of travel time: It could take a weapon four to six hours to reach a target in the 24-hour geosynchronous arc over the equator, where critical observation and applications satellites are located. But it's also a matter of accuracy and closing speed. Higher orbits pose much more of a challenge for weapons that depend on a fast relative closing speed for a “kill.”

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In lower orbits, the best defense is a good pretense. That is, a potential target may survive by not allowing its hunters to know where it is accurately enough to get a warhead on a collision course. Either the target follows an adequately unpredictable orbit (often only a matter of being a few miles away from where the killer expects it to be), or it is accompanied by decoys in nearby orbits.

Deploying a larger number of smaller satellites is also an option. Being able to launch replacement satellites quickly has been considered, but producing and stockpiling enough spare payloads and boosters — and then getting the payload activated quickly enough once it arrives in space — has proven to be an operational and engineering nightmare.

The last-ditch defense — actually trying to stop an incoming impactor — remains a science-fiction dream. And that is largely because the “kill mechanism” of the weapon is so very, very simple.

It’s a throwback to the first weapons our remote ancestors used on the African savannah: Hit the sucker with a rock.

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