China’s satellite shoot-down isn’t just a provocative, dangerous act, writes veteran space analyst Jim Oberg. It also marks the rise of a new kind of satellite-killing technology — one in which a weapon is shot directly from the ground, to the orbiter up on high.
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.
That’s because it’s hard to nail an orbiter, traveling hundreds of miles up at thousands of miles per hour, from the ground. The fact that the Chinese were able to do it could have troubling repercussions beyond space, as one commenter to the FPSPACE list notes:
Assuming the [Chinese target satellite] was on the order of 3 meters in size, and assuming the kill was made in direct ascent mode as opposed to co-orbiting mode, this test demonstrates the capability to achieve a velocity error on the order of 3 meters / ~1000 seconds, i.e., way less than 1 cm per second. This has obvious implications for their CEPs [Circular Error Probables, the accuracy] of Chinese ballistic missiles.
Now, Beijing seems to have cheated just a bit in this test, Oberg observes.
The last orbital data released by NORAD seem to show one end of the [Chinese target] 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 targets 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.
But even with some fudging, this remains a very serious technical accomplishment. Oberg’s piece has lots more — including some possible (repeat, possible) countermeasures to a satellite strike. Be sure to read the whole thing.
Of course, for a long time, directly attacking the orbiter with another piece of metal seemed like the least likely, least effective way to knock a satellite out. Since 2004, the U.S. Air Force has had in its arsenal a series of radio frequency jammers, to interfere with satellite operations. Three or four times a year, small groups of junior officers gather at an Air Force Research Laboratory facility in New Mexico to figure out how to take American satellites off-line using nothing more than sweet talk and off-the-shelf gear.
Then there are the lasers. Not only did China recently light up an American orbiter with a ground-based laser. But, as Dan Dupont reminds us, the U.S. military spent much of the 90’s testing out a satellite-shooting beam weapon of its own: the Mid-Infrared Advanced Chemical Laser, or “MIRACL.“
“In October 1997, the Air Force commissioned a test of an ASAT [anti-satellite] system based on the MIRACL laser,” the Union of Concerned Scientists notes. “This system was directed toward a satellite orbiting 420 km above the Earth. The MIRACL laser apparently had technical difficulties, but the results of the test were startling.”
A lower-power (30-watt) laser intended for alignment of the system and tracking of the satellite was the primary laser source used during the test, and it appeared that this lower-power laser was sufficiently powerful itself to blind the satellite temporarily, although it could not destroy the sensor. That a commercially available laser and a 1.5 m mirror could be an effective ASAT highlighted a US vulnerability that had not been fully appreciated. Although the Pentagon described the test as defensive (i.e., to learn about the vulnerability of US satellites to laser attack), manyin particular the Russiansexpressed concern about the offensive capabilities of this system and whether it constituted a breach of the ABM [anti-ballistic missile] Treaty, and formally requested negotiations on an ASAT weapon ban.
(Big ups: AT)
ALSO:
* China Tests Satellite Killer?
* China Space Attack: Unstoppable
* Satellite Killer’s Broad Impact
* Why Did China Smack the Sat?
* China Sat-Killer Not Yet Weapons Grade?
* Who Ordered the Satellite Strike?
Stupid question: Wouldn’t the Airborne Laser be a far better anti-sattelite weapon than it is an anti-missile weapon?
It sounds like Cold War II, now against China, but likely an undeclared Cold War. Weaponization of space, or say SDI II, may be an option with space base defense system to block anti-satellite systems to approach satellites.
>Wouldn’t the Airborne Laser be a far better anti-sattelite weapon than it is an anti-missile
>weapon?
There are different advantages and disadvantages of the two. Under atmosphere environment, directed energy is affected by weather conditions. However, it is still an option for the response time allowing countermeasures at the early stage the anti-satellite missile being launched.
Here is another question. Is China’s anti-satellite system only a system that has a reach against LEO satellites, or even above, up to GEO satellites? That makes a difference, at least for survivability of GEO satellites.
I would prefer SBL as part of countermeasures, and sapce rods if accurate enough to strike such anti-satellite missiles.
Maybe we will need more for our military budget, for more to spend on R&D for counter measures against the threat of such space related weapons of China.
And thank you China for all the new 20,000 mph space debris. Nice job.
What does Russia think of this?
All of this really is amazing. This is like three China pieces in a row. Terrorism is so yesterday
Am I the only one who can smell a whiff of paranoia here? The US is way ahead of China in launch systems, directed energy weapons, kinetic kill vehicles, and pretty much any other damn thing you can think of. But anyone else possessing any capability at all is a ‘threat’?
BT is right on, let’s give the money where it’s needed, not to counter some imaginary Yellow Peril.
US may be ahead of China in technology, but we cannot ignore the recent developments of China’s military. In recent years, China has been interested in building up their own Air Craft Carrier (Varyag), and has recently shown interests in purchasing CV fighters from Russia as well as bombers. China has also been interested and been doing R&D in building stealth fighters as well as stealth UAVs. Of course, training alone cannot be ignored for operating carriers and it requires years to let it function well enough. There are also threats of espionage from China. There has been reports of Chinese espionage activity in US, Canada, Japan, Australia, and Europe. It is not an immidiate threat that China will reach US soon, but the aggressiveness is enough for the potential to catch up. In political terms, China has engaged in political activities influencing governments, such as US, Japan, Australia, Zimbabwe, Nepal, Republic of Dominica, and maybe several others that I am not aware of. The news that a Chinese ex-diplomat that made an assylum to Australia for China’s attempt to politically colonize by fueling anti-US propaganda in Australia was shocking, as well as China has attempted to do in Japan.
there is only one pie. china can buy the pie goodies its billion plus needs, or take them.
buying is easier, but only as long as those who have want to sell.
taking, then, becomes viable.
so, question is.….where are the goodies that china wants/needs? not here in the US…but in those same places Japan once tried to corral them.
THATS where we’ll meet, hot…and why.
we once had a flag that featured a rattlesnake on it with the legend “don’t tread on me”…that dragon they have is far bigger and more dangerous than the rattler ever was.
What’s with all the technical complexity? If you know the orbital characteristics, all you need is a booster, solid fuel is best, and a payload of gravel. At 17,000 mph relative speed, a cloud of 3/4 inch stone (in fact, one 3/4 inch stone) should be more than sufficient!
KISS, always KISS!
Pedestrian said: “Here is another question. Is China’s anti-satellite system only a system that has a reach against LEO satellites, or even above, up to GEO satellites? That makes a difference, at least for survivability of GEO satellites.“
There’s a long way to go between LEO and GEO satellites (oh…another 22,000 miles or so). As such, the technology is completely different — a direct ascent ASAT weapon is not feasible, mostly due to the massive amount of delta-V required to get there. Additionally, time in transit to GEO is a lot longer, potentially allowing a target to pursue some evasive maneuvers.
“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.“
If, as some of nervously suspect, the Chinese ASAT is based on the DF-31, then one should remember that it’s likely to be road– and rail-mobile. And that China has east-west railroads, which means that launchers could be positioned near the ground track of a potential target rather than having to wait for a favorable pass.
Also, if this is a derivative of the DF-31, it will certainly be able to reach much higher altitudes than the 850 km of FY-1C.
If the Chinese are able to hit a bullet with a bullet, why is is so hard to believe that the U.S. cannot deploy a BMD system that will work?
It just goes to show that the development and deployment of a limited BMD system is a political, not a technical issue.
All they have to do is disable our GPS satellites to greatly inhibit our war fighting capabilities.
Our services depend GPS to an extremely high degree.
The higher tech we become, the more fragile get.
Need an example? Look at how they’re fighting us in Iraq.
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