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Rob Thornton
02-24-2008, 02:07 PM
Last week the U.S. Navy conducted quite a technological feat in destroying one of our own defunct satellites that was losing orbit and posed a serious enough potential risk to justify its targeting.

The Navy was tasked to shoot it down, and beyond the technical risk, there was at least some political risk.

I recently read an article that discussed how technically different the Chinese destruction of one of its satellites and our surfaced launched shoot down of one ours is different. There is also the open question of intent. I recently saw where Secretary Gates responded to Chinese and other states calls for openness regarding the details, something to the effect of "we'll be happy to share what we can". Even though the statement certainly preserves the right to withhold elements that could jeopardize our security, the statement itself is a narrative on openness. Indirectly I think it shows that our internal lines of communication within the U.S. Government allow its members to interact when events call for it - it gets to the issue of relative transparency in our foreign policy.

We've had discussions here about "hybrid", "blended", MCO, IW, UW, SSTRO, full spectrum, etc. We often discuss the influence of third parties - Iran, Russia, China, India, Israel, etc. We often discuss the need to build coalitions and regional capacity. We often discuss technology here - this was certainly a capability built on technology - a technology arguably beyond that of other states.

So when we "demonstrate" a capability like this, does it change things? How?Where does this fit? What are the positive and negative implications? Are there opportunities? How does it affect expectations? Ia this something we could see as complimentary to some of our other capabilities? How about deterrence - who would it deter, or not deter - why?

I don't think we should see this in a vacuum - I think if somebody else would have demonstrated this, we'd have brought it and discussed it along the lines of what direction should we take in our own military development - in that regard it makes me wonder how this event shapes military development of friends and enemies? From an enemy (or competitor) Do more resources go into developing, buying or stealing like or counter capabilities - or do you look for something along a niche or maybe the asymmetric line? Finally, how does a capability like this support us in ways beyond the obvious?


Best Regards, Rob

JJackson
02-24-2008, 05:20 PM
I had been writing this for another site but it may be of interest here. I have updated it a bit to include some info on the American missile test and there are links to MSN reports on the Chinese test. While the low altitude of this test means much of the resultant debris will re-enter fairly soon the forces involved in this explosion will have lifted some debris into higher orbits - which would not have occurred if the satellite had been allowed to re-enter unmolested. Those of you who have read posts of mine before will probably have gathered I would be happier with no military satellites in space but I would concede that GPS is useful and that accurate satellite surveillance - post Gary Powers - helped control some of the wilder speculation by US hawks on the state of Soviet missiles putting a slight check on the arms race.

Kessler’s Syndrome

"Space," it says, "is big. Really big. You just won't believe how vastly hugely mindboggingly big it is. I mean you may think it's a long way down the road to the chemist, but that's just peanuts to space." The Hitchhikers Guide to the Galaxy.

The above not withstanding bits of it are more equal than others (with apologies to Orwell) and we (man) are endangering some of the bits that are most important to us. Which brings us to Kessler’s Syndrome; a runaway chain reaction involving space debris. I have written a short introduction in the box at the end with a number of links for greater detail.
If you are happy with the Jargon skip it, if not read it now.
Kessler’s warning relates to the LEO but with the importance of the GEO orbit the same could apply to both. If a satellite is hit - or worse still explodes - it may produce many high speed pieces of space debris, if there are enough satellites and other pieces of space junk in the vicinity a chain reaction can destroy all satellites in that orbital region and leave a dense debris field rendering any further attempts to enter orbit extremely hazardous. This could bar us from entering space for 1000s of years. Unlike criticality in a Uranium fission reaction - where 3 neutrons are released and at least one needs to impact with a fissile nucleus for the reaction to be sustained - here an impact could produce none or tens of thousands of debris pieces making it much less predictable. About a year ago China decided to hit one of their defunct satellites with a projectile in a test – this test doubled the debris field in that LEO orbital area (the NY Times has an excellent graphic showing how in just a few days this had distributed itself all around the globe. Also shows a Hubble solar panel with all of its hits - Links below). The US has now hit one of their failed spy satellites with a rocket. (They claim to prevent danger to humans from Hydrazine fuel but a quick look at N2H4 will show this as miscible with water, has freezing and boiling points similar to water and a 3-3-3 NFPA 704 rating so not exactly a major threat to survive re-entry nor to life on the ground if it does).

Is this syndrome imminent: probably not but the lead times are long and the orbital debris has a long half-life so it is important to ensure all new launches and satellites are designed to minimise the dangers and that our nations militaries are stopped from adding to the problem. When I say not imminent that is based on accidental initiation of the syndrome, the very high yield of fragments means the deliberate cascade initiation is not overly complicated for a power with the requisite missile technology who thought it was in their best interests to deny LEO to all. The IAA study, linked to in the first post, covers many of the simpler remedies (some are as simple as not painting satellites and rockets as paint is layered and brittle and can produce vast numbers of shards where a micrometeorite impact on metal won’t).
For an example of what not to do see The Westford Needles Project (http://en.wikipedia.org/wiki/Project_West_Ford)



The principles are all fairly simple ‘for every action there is an equal and opposite reaction’ so when a rocket goes up – or sideways - propellant is ejected at speed in the opposite direction. Getting a Kg of payload into orbit requires enormous amounts of energy and the higher the orbit the more energy required (Delta-v (http://en.wikipedia.org/wiki/Delta-v) is a measure of the energy required to move from one state to another). The most popular orbits are low earth (LEO - because they are cheapest to achieve) and Geosynchronous/Geostationary (GES/GEO as they allow station keeping above a fixed ground position at a minimal fuel requirement). Kinetic Energy is calculated as the product of mass & velocity; in the absence of air resistance velocities are high, typically 10km/sec, at these speeds a 3mm particle would pack the same punch as a bowling ball at 100km/hr. The atmosphere has no clear top it just thins into space, 75% is within the first 11km and re-entry effects can be noticed from about 120km but to be totally clear of all atmosphere 10,000km is about right. A bodies gravitational effects are taken to act from it centre of gravity (in the earth’s case this is the middle of the core) and fall off in line with the reverse square law. The distance to the Earth’s surface is 6370km. From the surface LEO covers 160 to 2000km with GEO at 35,794km (other sites of interest: International Space Station ISS 500km, GPS 20,230, Hubble 589km)

Position Paper on Space Debris Mitigation
Implementing Zero Debris Creation Zones
http://iaaweb.org/iaa/Studies/spacedebrismitigation.pdf

The Military Use of Space
http://www.parliament.uk/documents/upload/postpn273.pdf

US 'to shoot down spy satellite'
http://news.bbc.co.uk/2/hi/americas/7245578.stm
http://news.bbc.co.uk/2/hi/americas/7256741.stm

The military uses of space
http://www.parliament.uk/documents/upload/postpn273.pdf

Impact suspected for loss of Russian satellite
http://space.newscientist.com/article/dn8934-impact-suspected-for-loss-of-russian-satellite.html

Debris Mitigation Improves, but More Work Urged
http://www.space.com/spacenews/archive06/Geo_013006.html

Geostationary Orbit Impact Detector (GORID)
http://esapub.esrin.esa.it/pff/pffv7n1/drov7n1.htm

Littered Skies (NY Times animation and graphic on debris damage & distribution)
http://www.nytimes.com/2007/02/06/science/20070206_ORBIT_GRAPHIC.html

What I should have added was why this matters. My interest is largely in what we can learn about the universe (and earth) from space based instruments but more generally satellites are now critical for weather forecasting (and climate change data), transport (shipping, planes &, increasingly, road transport are ever more reliant on GPS - sextant futures might be a good investment), real-time news media are all satellite dependent and then there is the military ...

LawVol
03-23-2008, 10:00 PM
Some would argue that our satellite operation was a response to the Chinese ASAT test and/or a response to the joint Russian/Chinese anti-space weapons treaty. Maybe they are right. There has been alot of ink spilled arguing that America has now increased the chances for a space weapons race. Little is apparently said of the fact that America last tested an ASAT capability in 1985 and most likely had no real interst in pursuing this capability any further until the Chinese ASAT test.

I'm told by an aerospace engineer I know that the technological feat was not that we hit the satellite - the Chinese satellite they took out was in a higher orbit and thus more difficult to hit - but that we were able to alter available technology so quickly to do it. Although the fact that our satellite was essentially dead and had little to no heat signature may suggest a new or special capability.

This could mean that the US still has no real interest in pursuing this capability but wanted to demonstrate the ability to do so should China continue on its present course. As many argue, sine America relies so much on space technology, we have the most to lose. One could look at the recent shoot down as generating a space race or as a way of simply saying "Look China, we know what you're up to and we can match (or even surpass) you capability very quickly. Let sleeping dogs lie."

Of course, looking at USAF doctrine, one can see that offensive space operations are contemplated. What are the implications of this? Having the most to lose in space means that America must act to protect its assets. We cannot count on the ambivalence of our enemies -- they will most assuredly move to counteract our advantage in any way possible. Threats to our space assets would have an effect down to the tactical level. Although some would argue that a treaty banning space weapons is the way to go (that this would protect our assets from attack), how can this be so if such treaties are not verifiable? After all ASAT technology can be hidden in civilian satellites or can be earth bound weapons. Are we really going to leave our national security interests in space to the integrity of our enemies? China and Russia already have this ability. The stuff I read indicates that Iran and possibly India and North Korea are working on this.

I see the weaponization of space as inevitable. In looking at the first three dimensions of war (land, sea, air), we see that man could not resist the urge (need?) to weaponize. Why should space be any different? If it is indeed inevitable, perhaps the best we can hope for is a sort of mutually assured destruction (MAD) in space. MAD originated in the Cold War as a result of nuclear weapons. In space, having ASAT capability is the equivalent of nukes. Since everyone relies on satellite technology for everything from cell phones to targeting, why would anyone want to threaten these assests? Of course, this assumes participation in the global economic system, something AQI et al does not want to do. So this MAD in space is good for nation-to-nation threat ala the Cold War, but no good against terrorists. Right now, however, terrorists do not have this capability but could they in the future? If so, waht are the implications of this?

Entropy
03-23-2008, 10:21 PM
Personally I think the US has an incentive to keep space as demilitarized as possible. Of course this test and the Chinese test call into question the very definition of militarization of space since the weapons were ground and not space-based. Still, the US is both the most dominant in space and also the most vulnerable. Instead of working toward offensive space operations, I think the US would be better served by further limiting such weapons through treaty and preparing some redundancy in the space system.

LawVol
03-23-2008, 11:42 PM
Personally I think the US has an incentive to keep space as demilitarized as possible. Of course this test and the Chinese test call into question the very definition of militarization of space since the weapons were ground and not space-based. Still, the US is both the most dominant in space and also the most vulnerable. Instead of working toward offensive space operations, I think the US would be better served by further limiting such weapons through treaty and preparing some redundancy in the space system.

If a treaty could be verified, maybe this would be a good idea. My problem is with the ability to verify that a country is indeed obeying its provisions. An article on the topic: Space Weapons Agreements, etc. (http://www.thespacereview.com/article/1078/1)

The Russian/Chinese treaty proposal (here (http://rescommunis.wordpress.com/2008/02/20/draft-treaty-on-the-prevention-of-the-placement-of-weapons-in-outer-space-the-threat-or-use-of-force-against-outer-space-objects/)) is widely viewed as unenforceable. Since it is unenforceable, we must operate under the assumption that our adversaries will not abide by it if not doing so is in their best interests. However, given our cultural adherence to the rule of law, our adversaries might have us over a barrel by practicing what Gen Dunlap calls lawfare. To quote the article cited above:


Most proposed space arms control agreements, notably the ones recently put forward by China and Russia, are not even close to being technically verifiable. Moreover, they seem to know this. Their goal is to set out their terms and then sit back and watch while the Americans tie themselves up in legalistic knots over definitions and doctrinal and/or philosophical questions.
By entering into a treaty, are we not then tying our own hands without verifiably tying the hands of our adversaries? Additionally, do we not then jeopardize our operations in the current long war?

Stan
03-25-2008, 08:17 AM
Hey Rob !

Aside from the obvious concerns about this dud satellite and our means of plucking it from the sky, what of the enormous cost to the American taxpayer, and if nothing else, the news about Raytheon Missile Systems recently winning a 4.5 billion dollar contract (for more of those juiced AM-3s)? FMS to Japan for 27 of the 102 missiles being procured/built ? Huh ?
Hmmm, really strange Sierra going on there. Why build 102 missiles, and suddenly have 27 left over to sell to Japan :confused: 3% accessorial charges based on the full standard price ? That’s big bucks! Wonder where that cash will go ? Another satellite :eek:

Yesterday's Aviation Week (http://www.aviationweek.com/aw/generic/story_channel.jsp?channel=defense&id=news/ASAT032408.xml)has a short, very carefully worded article regarding the shoot down and our perceived capabilities.


...there’s still a lot the experts don’t know about what happens in space.

“We didn’t predict an explosion,” says Rear Adm. Brad Hicks, U.S. Navy manager of the Aegis air and space defense program. “But the hydrazine tank did burn for tens of seconds.

While U.S. officials say it was a one-time event, they also say they learned a lot that might not have to be repeated for a second anti-satellite (ASAT) mission.

There were unexpected obstacles. “[The dead satellite] was not stable,” Hicks says. “It was rolling and tumbling and [its gyration] wasn’t always the same from one orbit to another, which added to the technical challenge.

Regards, Stan


Last week the U.S. Navy conducted quite a technological feat in destroying one of our own defunct satellites that was losing orbit and posed a serious enough potential risk to justify its targeting.

The Navy was tasked to shoot it down, and beyond the technical risk, there was at least some political risk.
Best Regards, Rob

Hacksaw
03-25-2008, 07:50 PM
I do not consider myself a space SME (but I did sleep at a Holiday Inn Express, carried the identifier, and wrote a monograph), but I think we ought to listen to the man who understands Kessler...

If I thought the paper was worth it, I'd attach it to this post, but alas its mostly drivel written in drunken haze...

However, a few insights are worth mentioning...

By 2010, cumulative American investment in space
alone will reach $500-$600 billion or about as
much as the value of present American investments
in Europe. Both our military readiness and
economic vitality are inextricably linked to the
health of our military space systems. The
dependence of our national security on orbiting
satellites makes space systems a tempting target
for terrorism and adversarial military operations.
We will continue our emphasis on this emerging
te~hnology.~In congressional
testimony on March 8, 2000, General Ralph E. Eberhart,
Commander in Chief United States Space Command

In the fifteenth and sixteenth centuries European
powers waxed and waned in their enthusiasm for
transatlantic exploration, but once the New World
was discovered, there was no turning back. In the
same way now, our drive into space may wax and
wane, but the competing armies of too many
countries are now far too dependent on missiles
and satellites to imagine them ignoring the
heavens. It is now becoming clear that in the
future the first thing any regional power involved
in conflict with the United States will do is try
to scratch out its eyes in the sky.9 Alvin and Heidi Toffler

A common misperception concerning space weapons is that
current treaty obligations prohibit the US from pursuing an
aggressive space weapons fielding program. This is false
with the exception of those activities prohibited in the
Outer Space and Anti-Ballistic Missile Treaties. Me

Hacksaw
03-25-2008, 07:52 PM
still needed editing, oh well.... please note that the paper was written in spring 2000. Not sure if I should admit this but I advocated in the same paper that we should pull out of the ABM Treaty, was roundly pillared by the evaluation committee that the US would never pull out of that treaty... well you know the rest of the story..

live well and row