US To Shoot Down Dying Satellite

A user writes "US officials say that the Pentagon is planning to shoot down a broken spy satellite expected to hit the Earth in early March. We discussed the device's decaying orbit late last month. The Associated Press has learned that the option preferred by the Bush administration will be to fire a missile from a U.S. Navy cruiser, and shoot down the satellite before it enters Earth's atmosphere. 'A key concern ... was the debris created by Chinese satellite's destruction -- and that will also be a focus now, as the U.S. determines exactly when and under what circumstances to shoot down its errant satellite. The military will have to choose a time and a location that will avoid to the greatest degree any damage to other satellites in the sky. Also, there is the possibility that large pieces could remain, and either stay in orbit where they can collide with other satellites or possibly fall to Earth.'"

Our secrets are worth more than your secrets!

[stevedcc (1000313)]

"We consider our secrets to be worth space junk, but your security not to be".

Is this really anything else? The US is willing to protect it's secrets, China was trying to ensure they could protect theirs. Both are sovereign nations with the technology and ability to make these decisions.

The only way issues like this will ever be resolved is by allowing some intra-national body to have either approval or veto powers, but nobody wants to be told what they can/can't do.

Re:Our secrets are worth more than your secrets!

[crymeph0 (682581)]

That may be the actual thought process at the Pentagon, but there is actually a sound justification for shooting down this satellite: TFA says there is a 1 percent chance debris could hit a populated area. That is well above the danger threshold NASA, etc. allow when choosing where to perform a controlled deorbit. 1 percent doesn't seem like a lot, until you realize how many satellites are up there, and they all must come down eventually.

Even if safety weren't a genuine concern, it would still be acceptable to shoot down this particular satellite, in my uninformed opinion. I believe this because it's already in a decaying orbit that will bring it down within two months. Any debris created by the explosion will be in a similar or slightly higher orbit, and will also decay to GLO (ground-level orbit) in a reasonably short time. The satellite the Chinese shot down was in a much higher orbit, and that debris is likely to stay up for *hundreds* of years, IIRC. If they had shot down a satellite in a similar orbit as this, there wouldn't be a stink about the debris, only about the naked attempt at weaponizing space.

China's debris to remain for thousands of years...

[KH2002 (547812)]

The satellite the Chinese shot down was in a much higher orbit, and that debris is likely to stay up for *hundreds* of years...

It's worse than that -- according to MIT space security expert Geoffrey Forden [wired.com], "China's debris will be in orbit for thousands of years (and I mean that literally). ... [The US shoot-down] would create a debris field but no where near the sort of debris catastrophe that China created last year."

The two shoot-downs are not equivalent, which of course won't prevent agenda-driven comparisons...

Still dangerous

[mangu (126918)]

[The US shoot-down] would create a debris field but no where near the sort of debris catastrophe that China created last year

Letting the satellite re-enter atmosphere unbroken would be the only way to make sure it does NOT create a debris field.

A satellite is not an airplane, there's no way to "shoot" it down. Breaking it in pieces will not bring it down, it's atmospheric drag that's doing it. All the Pentagon is doing is trying to make sure that it breaks down into pieces small enough to protect their military secrets.

By blowing up the satellite with a missile they have no control on how it's going to break, all they can do is estimate on the most probable breaking patterns. They cannot be sure that the remaining pieces will be of such sizes and shapes to re-enter the atmosphere in a predictable manner and time.

There is still the possibility that some of the largest fragments will hit some populated area. The fuel tanks, which are compact and very strongly built, will have a rather good chance of surviving, and reaching the earth's surface still containing some of that extremely toxic hydrazine (so toxic that a drop can kill a person). Besides, the explosion will inevitably send some fragments into a higher orbit, and possibly damage other satellites.

Blowing up a decaying satellite with a missile is, IMHO, the stupidest thing to do, and I have been an engineer working with satellite control systems for nearly 24 years by now.

Re:Still dangerous without the shot?

[mangu (126918)]

would they not just survive reentry sans the missile shot and still pose a threat to those on the ground?

Yes, they would. People on the ground will always be at some danger when you put an 11-ton satellite in low earth orbit.

But it's easier to predict the impact point of a body that has a well known shape and orbit than that of a body that has been torn apart and pushed in random ways by an explosion.

Re:Still dangerous

[mangu (126918)]

It it were to be hit (hard) from the front relative to it velocity vector there would be enough loss of momentum to cause it to come down

Sure, but how hard can you hit? It's not as if it were hitting a stone wall, it's hitting an exploding missile, that is, a fire ball. It's travelling at close to 8000 meters, or five miles, per second.

The densest parts, like batteries, fuel tanks, and possibly the main camera mirror, will go through that explosion ten times faster than a bullet. Do explosions stop bullets? Not unless it's precisely concentrated at the exact point [wikipedia.org]. There is no way the explosion could transfer enough momentum to the densest parts to significantly affect their orbit.

The flimsiest parts like, for instance, the solar panels, will be shredded to very small pieces by the explosion, of course, but those are exactly the parts that would burn first when entering the atmosphere.

Re:Still dangerous

[SETIGuy (33768)]

Sure, but how hard can you hit? It's not as if it were hitting a stone wall, it's hitting an exploding missile, that is, a fire ball. It's travelling at close to 8000 meters, or five miles, per second.

Trying to destroy a spacecraft with a fireball would be pretty stupid, and I doubt the U.S. military would be that stupid. What you want is a slowly expanding cloud of massive objects to intersect the satellite at high velocity. Lot's of explosives aren't necessary because you don't need to get the shrapnel to high velocity.

Since you've got 8 km/s of orbital velocity and probably around 3 km/s on the interceptor, you're probably talking about 10 km/s at the intercept. The heat of vaporization of iron is 250 kJ/kg and this thing has a mass of 11 tons, so we can assume 2.7 GJ will do quite a number on this satellite. Sure, it's not made of iron, but you don't really need to liquify it to destroy it. Satellites are usually only built to survive launch stresses, not impacts.

Anyhow at an impact velocity of 10 km/s 2.7 GJ would require a impactors with a total mass of 50 kg, probably in the form of lead or depleted uranium for compactness. To be thorough in your destruction, you probably want multiple small impactors, say 500 of them at 100 grams each. The total mass of the warhead depends upon how close you can get to the target. If you could be ensured a direct hit, 50kg would suffice. But it's likely that this won't be a direct hit, so you'll need to cover a larger area than the satellite itself.

We'll assume the satellite projects an aspect of 600 square meters (say about 60 meters by 10 meters) and that our shot cloud covers a circular area. Once your impact parameter exceeds 14 meters your warhead size goes up as the square of the distance. At 25 meters, you need 160 kg. At 50 meters you need 650 kg. At 100 meters you need 2.6 tons. At a kilometer you need 260 tons.

The only thing determined by the yield of the charge that scatters these impactors is the timing. How long before impact do you need to set it off and how accurate does your timing need to be? These are left as an exercise for the reader. If I were designing the thing I'd keep the scattering charge as small as possible. The bulk of the constraints are set by the trajectory. In a head on trajectory, there is nothing wrong with scattering the impactors 5 seconds or more before impact. For an interceptor that travels vertically, the maximum timing probably depends upon atmospheric properties.

Given the geometry of the likely impacts, it is unlikely there would be significant amounts of ejecta inserted into long lasting orbits. The worst cases would be insertions into elliptical orbits, but they would circularize quickly at low altitude due to the low perigee. It should be possible to choose in impact point that will minimize risk to other vehicles.

FWIW, I do not design space weaponry, and I do not know the actual capabilities of U.S. anti-satellite weaponry. I just know how to break things in a practical and sometimes dramatic manner.

Re:

[Nefarious Wheel (628136)]

until you realize how many satellites are up there, and they all must come down eventually.

What goes up must come down, eh?

Nope.

It depends entirely on the radius of the orbit, the orbital velocity, and the amount of upper atmosphere remaining at that altitude. If the orbit is good and the drag nil, it'll stay up there. Or at least that's how orbital mechanics worked when I was a kid.

Re:Our secrets are worth more than your secrets!

[amorsen (7485)]

I didn't mean "must" in the "great hand of physics will pull the satellite to its inevitable doom" sense, but rather in the "we intentionally deorbit all our satellites after their useful life is over to avoid filling the skies with debris" sense.

And how exactly does that happen? Geostationary satellites get pushed slightly higher so they don't take up space in the geostationary orbit, but they never bring enough fuel to be able to get back to Earth.

And even without intentionally deorbiting them, most satellites experience enough atmospheric drag (i.e. not 'nil') to bring them down in tens to hundreds of years - not a legacy you'd like to leave your grandchildren.

Again, wrong for geostationary (and lots of other orbits).

Re:Our secrets are worth more than your secrets!

[evanbd (210358)]

To be fair, the space junk isn't equivalent -- the junk from a satellite that's about to reenter will also reenter promptly, whereas the junk from a satellite in a high orbit will remain in a high orbit. The impact won't actually alter the orbital parameters of the junk as much as you might expect; nearly all of it will reenter promptly, and I'd be surprised if any of it managed to get high enough to present a danger to other satellites (the satellite in question is well below normal operating altitudes).

Of course, I'm not trying to say the US isn't guilty of hypocrisy -- just that this case isn't as bad as you make it out to be.

Re:Our secrets are worth more than your secrets!

[smooth wombat (796938)]

Yes, all we need is a world dictatorship to tell sovereign nations what they are permitted to do.

Such as telling certain countries they are not allowed to have nuclear weapons while allowing, and even encouraging, others to do so. Or telling certain countries they cannot have wmds in general and then invading that country to prove they don't have any. Or did you mean not trading with a country until it changes its political climate?

You mean a world dictatorship telling soverign nations what they are permitted to do like that, right?

Target practice or....?

[link5280 (1141253)]

Since this is a severely decayed orbit I would suspect most debris to reenter within the same timeframe or shortly thereafter, 1-2 weeks. I also doubt it will create any debris fields in a useful orbit. Anyway, the only reason the military would do this in the first place is to ensure a complete destruction of the spacecraft. Break it up into small pieces beforehand and the reentry will take care of the rest. Otherwise, why bother! Or target practice?

Re:Target practice or....?

[p0tat03 (985078)]

A bit of both I suppose. It's not every day you get to do a live-fire exercise of your satellite-attacking technologies... Not to mention it's not every day you get a real live test of just how good your satellite's anti-missile technologies are! Either way somebody in the military wins :P

Big chunks will no doubt re-enter the atmosphere relatively quickly, and they should be small enough that they will burn up completely in upon re-entry, which I think was the whole point of this exercise...

Re:Target practice or....?

[Sen.NullProcPntr (855073)]

Big chunks will no doubt re-enter the atmosphere relatively quickly, and they should be small enough that they will burn up completely in upon re-entry, which I think was the whole point of this exercise...

What about the force of the explosion? With no air resistance isn't just as likely that some pieces (of both the satellite and the missile) will end up in higher orbit thus the concern for collision with other satellites.

Re:Target practice or....?

[Trails (629752)]

That's probably unlikely. Keep in mind that a higher orbit requires more than just altitude, it also requires angular velocity. The explosion would have to impart enough kinetic energy to not just overcome the gravitational potential to reach the altitude of other sats, but also to impart the necessary angular velocity about the earth.

The US military is probably aware of the max velocity of debris from their different ordinance. As much as the US administration is full of morons, the physicists designing the ordinance and planning stuff like this are quite competent.

Re:Target practice or....?

[Jeremi (14640)]

That's nice that you know the volume of a circle

Just to be a smartass, I have to point out that the volume of a circle is zero, not pi*r^2.

Re:Target practice or....?

[by Anonymous Coward]

Short answer: No

Longer answer: The orbit of a satellite can be determined by the position and the velocity at any time. Orbits are changed by changing the velocity of a satellite, but the old and new orbits will continue to intersect at the point where the velocity was changed.

Changing to a higher orbit will require two changes in velocity and uses a transfer orbit that intersects both orbits. One velocity change puts the satellite into the transfer orbit and one velocity change puts it into the final orbit. Usually, the two velocity changes are at opposite sides of the transfer orbit (half an orbit period apart).

I assume that this will use a warhead instead of a rocket motor for a single change of velocity, but there will only be one change of velocity. If the intercept takes place at lowest point of the current orbit then any debris will be in an orbit that will return the debris to the point of intercept. If it is already brushing the atmosphere then reentry is inevitable and the time to reentry will only depend on the ratio of the mass to air drag of the object (small heavy objects will stay in orbit longer).

Normal precautions of staying out of the temporary orbits of the debris does apply.

_Richard

Re:

[gnick (1211984)]

Or target practice?

Don't underestimate the value of target practice. Shooting down a satellite is no simple matter. The Chinese engineers decided that they couldn't just hit one with a missile, so they sent up a missile capable of firing a separate payload once it got close enough. I'm sure the US would love an excuse to try out a satellite killer. And, since it's been made clear what a hazard this thing could be if it falls to earth, they can try out their new toy AND protect the planet from their defunct satellite.

Re:Target practice or....?

[imipak (254310)]

I say we launch it into orbit, and nuke it from the surface. It's the only way to be sure.

Ulterior motive?

[TripMaster Monkey (862126)]

It seems to me that there's no real reason to "shoot down" this satellite, except as a test/demonstration of our ability to shoot down satellites (not necessarily our own)...

Re:Ulterior motive?

[Iphtashu Fitz (263795)]

It seems to me that there's no real reason to "shoot down" this satellite, except as a test/demonstration of our ability to shoot down satellites

That, or there's some technology on the satellite that they don't want to risk falling (literally) into the hands of another country.

Re:Ulterior motive?

[jellomizer (103300)]

I would say it is a kill two birds with one stone.
A. If push comes to shove they want to be able to shoot down emeny satellites.
B. They don't want the technology/information going to an other countries hands.
C. To show that we can, prevent other people from knocking out our own satellites.

Re:Ulterior motive?

[TripMaster Monkey (862126)]

From a related story [nytimes.com] (emphasis mine):

The orbit of Solar Max, a 5,000-pound satellite that collected information on solar flares for nine years, has deteriorated to the point that the spacecraft should crash back to earth late this week, the space agency said today.

Most of the craft will burn up in the atmosphere, but about a dozen pieces of three to five pounds each, plus one piece of about 100 pounds, are expected to come back down to earth. The debris could fall anywhere on earth from 28 degrees north to 28 degrees south of the Equator.

And from TFA (again, emphasis mine):

It is not known where the satellite will hit. But officials familiar with the situation say about half of the 5,000-pound spacecraft is expected to survive its blazing descent through the atmosphere and will scatter debris -- some of it potentially hazardous -- over several hundred miles.

It doesn't seem as if "shooting down" the satellite is really going to cause much more damage than re-entry and impact will...for this reason, my money's on either target practice for our benefit, or, more likely, a not-so-subtle demonstration of our space superiority.

Re:

[YrWrstNtmr (564987)]

It doesn't seem as if "shooting down" the satellite is really going to cause much more damage than re-entry and impact will...for this reason, my money's on either target practice for our benefit, or, more likely, a not-so-subtle demonstration of our space superiority.

And, we can (sorta) choose where the pieces come down, instead of relying on mere chance. My guess is they'll bring it down over the ocean.

Re:Ulterior motive?

[AJWM (19027)]

You can learn a lot from a busted piece of machinery.

Heh, or not. One of the things Britain did during WW II was to leave bits of busted machinery (electronics) that not only never worked, but were designed to be deliberately misleading, at the occasional aircraft crash site in German-occupied territory. The idea was to keep German radar scientists, etc, busy chasing down wrong paths if/when they recovered the equipment. (Which they did; recovering any kind of radar-related gear from Allied aircraft was a high priority for them.)

Re:Ulterior motive?

[stevedcc (1000313)]

It's a spy satellite and it's so big that some of it's gonna crash. What if that's over Iran/N Korea/China? You think the US wants them picking apart the remains of classified technology? They have a reason, it's just not necessarily any better than China's logic in testing their ability to destroy satellites (protect themselves from other people's spy satellites). Unless you think that the US's reason is better because it's the US, and China's worse, because it's China.

Re:

[msuarezalvarez (667058)]

As opposed to the US, which has brought so much good to the world lately, I guess.

(By the way, China is as communist as the US is a free market...)

Ballistic Missile Defense

[iamlucky13 (795185)]

I thought it was obvious, but none of the posters so far seem to have picked up on it. This is a further test of the ballistic missile defense program we've been spending $$$ for the last decade. In particular, the SM-3 Aegis Missile Defense System. [wikipedia.org] One of the bonuses is this will be testing the missile under less strictly defined conditions.

The program has been in the development and test phase since about 2000, and undergoing tests of increasing difficulty, but always under predefined conditions. The tests are also expensive to orchestrate, typically involving several naval vessels, and a lot of ground support from both the navy and contractors, a lot of documentation, and a target missile that itself probably costs several million dollars. Here they've got a target that won't behave as predictably and costs nothing (well sort of...It's a spy satellite that failed to reach the proper orbit). I'm not sure they even know when or where it will come down yet.

This isn't necessarily a good demonstration of our ability to shoot down satellites. The officially released specs say it has a maximum altitude of 160 km. Most satellites orbit higher than that. However, the actual performance is classified and probably somewhat greater.

It's also not something new. We tested anti-satellite weapons in the 80's, although those are now past their shelf life and the response time was slow. In the 60's we developed a system called Nike Zeus that had an altitude ceiling of about 300 km. It wasn't accurate enough to directly hit a ballistic missile or satellite to achieve a kinetic kill like the SM-3 does, but with a 40 kiloton nuclear warhead, that didn't much matter. It was never tested with a live warhead and it would have been messy to use (damages anything else nearby, terrible EM interference on the ground, etc), but it was something.

Oh bullshit.

[Jafafa Hots (580169)]

Satellites have been falling ever since we started putting them up, its no real threat.

The reson we are doing this is obvious - to demonstrate to the world (and the Chinese) that was have functional ASAT capability.

Re:Oh bullshit.

[scheme (19778)]

Satellites have been falling ever since we started putting them up, its no real threat.

The reson we are doing this is obvious - to demonstrate to the world (and the Chinese) that was have functional ASAT capability.

I think the reason is more because various agencies are worried that the satellite will end up falling in someplace while Russia or China and the intact pieces will give these countries examples to reverse engineer or clues as to US capabilities. I believe the satellite is supposed to be the newest generation of spy sats so it's probably full of interesting little tech.

Re:

[malakai (136531)]

This is my thoughts as well. What scares/embarsses me is that we seem to have not thought of this ahead of time and so there is no built-in self destruct capability.

Or, we have a self-destuct system and one of it's requirements is communication with ground.

In that case I guess I'd have liked to of seen some built in structural weakness. Some sort of failsafe so that if the satellite were to re-enter the atmosphere and begin to burn up, some ignitable material would ensure a thorough burn/destruction of the

Re:Oh bullshit.

[AvitarX (172628)]

Self destruct systems have mass and volume. That is a very tight resource on something sent into space.

Re:Oh bullshit.

[Lumpy (12016)]

Bullshit on your bullshit.

It's a brand new spy satellite that failed on deployment. It's chock full of the highest tech we could stuff in it.

I'd blow it up too if it was mine, there's a crapload of technology that even after reentry would be of HUGE value to many many people on this planet.

Re:Oh bullshit.

[Jafafa Hots (580169)]

Well, that's all well and good, but YOU read the fucking ARTICLE.

no, it's not the hydrazine

[Reality Master 201 (578873)]

With a boiling point of 114C, I'd imagine the bulk of the hydrazine would be gone well before the thing hit the ground. This is about destroying whatever's on the satellite and showing off ASAT capability.

As for the PR damage of killing whoever comes across the fuel, after the whole Iraq war thing, I think it can be conclusively and uncontroversially stated that one thing the Bush administration doesn't give two shits about is bad PR.

Not the same as Chinese Test

[usul294 (1163169)]

This satellite was never able to communicate to the ground. Its orbit was never finished off, which is why it decayed so much as to reenter the atmosphere after 15 months after launch. If they shoot this satellite down, the pieces will still almost all re-enter. The main reason for shooting it down, more than likely is to make sure the fuel doesn't make it past the very upper atmosphere, as well as to ensure that no one unscrupulous gets any technology. The kinetic energy delivered by the missile won't overcome the energy needed to kick the debris back into orbit, so there won't be a debris field.

let this be a lesson to NASA/JPL (whoever)

[FudRucker (866063)]

next time they build a satellite it would be a good idea to put a self destruct in it that can be activated remotely, cheaper and more reliable than shooting missiles at it...

Re:let this be a lesson to NASA/JPL (whoever)

[stevedcc (1000313)]

next time they build a satellite it would be a good idea to put a self destruct in it that can be activated remotely, cheaper and more reliable than shooting missiles at it...

Unless of course, the satellite stopped working because it's computer is bust. Then you'd have a big lump of explosives rolling around in space, and no control over it.

Re:

[moderatorrater (1095745)]

Great idea. Then the smart ass 12 year old Polish kid's going to use a TV remote to blow it up. Aside from the added weight and technical complexity that this would add to the satellite, if those codes get hacked it's millions if not billions of dollars down the toilet. Maybe more, if they detonated the satellites at a strategically advantageous time.

They are spinning the media with a scare story

[Ellis D. Tripp (755736)]

about the hydrazine fuel onboard, and the hazard it would pose to anyone on the ground, as if the fuel tanks would survive the breakup and atmospheric heating of the re-entry.

Looks like a great chance for the Bush regime to pull off an ASAT test, with a ready-made cover story to deflect blame for all the space junk it will create.

Cost Effectiveness.

[gandhi_2 (1108023)]

Since the Chinese have proven they can do this, it's reasonable to assume they can do it cheaper. Maybe they pentagon could outsource this satellite shoot-down.

You know, if the pentagon REALLY wanted to come across as bad ass, they wouldn't have told anyone it was a bad satellite. Then we could show the world we'll shoot down our own satellites just cause we can. Like a diplomatic "Don't you know i'm locco, esse?"

Shooting it down?

[sm62704 (957197)]

It's already coming down, isn't it? Wouldn';t they be shooting it UP?

That makes a better headline anyway, "US To Shoot Up".

Once gain - tinfoil over facts

[DerekLyons (302214)]

For a supposedly technical site, it seems very few Slashdotters are familiar with the tecnichal issues - or even bother to try. Rants before facts seems to be the motto.
 
This is very unlikely to add to the space junk problem - because this bird is in a decaying orbit. You further reduce the chances by waiting as late as possible (when the bird has been greatly slowed). You further reduce the risks by arranging your intercept geometry such that few (or no) pieces are boosted towards or into stable orbits.
 
It's not nearly as simple as "oh n0es, bl0w1ng stuffs up 1n spac3 m3ans mor3 spac3 junk !!11!!!1111!!111".

I often wondered

[kellyb9 (954229)]

I've often wondered what aliens might think if they were to visit earth and see us shooting missles at our own satellites as means of getting them down. On one side of the coin, we might look really badass.

Re:Incompetent

[Domint (1111399)]

Why not use those thrusters to drop it into the ocean at a planned location with the Navy there to pick it up on splashdown.

Kind of hard to do that when the master CPU fails on boot-up, which is the whole reason why something needs to be done about it. It is literally out of control.

Re:Incompetent

[QuantumRiff (120817)]

Did you even read the linked article? The satellite has lost all contact. It has rocket fuel, yes, but there is no way to communicate with it and tell it to fire the thrusters. As for the Navy picking it up, that is logistically a pain in the ass. Even when you can control the splashdown, you can get it to within a few hundred square miles. (lots of variance in air temperature, density, and wind) By the time a boat or helicopter could get to the actual crash site, it would be several thousand feet below the surface of the water. (which i'm sure the govt prefers...) Rocket boosters they pick up, but only because they are specifically designed to float.

Re:Incompetent

[ddusza (775603)]

Yes sir, can you try typing Ctrl-Alt-Delete? Oh, that didn't work? Hmmmm, can you try turning the power off and back on again? No? Well, I'm afraid we are just going to (trouble)shoot it remotely from one of our Tech Support Cruisers.... The NEW world of Tech Support

Re:

[schematix (533634)]

If they're going to the trouble of launching a rocket to intercept the satellite, why don't they build a small booster which could attach to the satellite and perform a controlled de-orbit? This would allow them to choose the point of re-entry to protect whatever secrets may be on board.

The problem with your idea comes down to it being far too complex of a process for the intended result. Launching a rocket to match up with another satellite is much more difficult than in sounds. The bottom line is that

Re:

[Oktober Sunset (838224)]

Ohhhh, they could launch it from a hollowed out volcano and it could capture space capsules too and hold the astronauts hostage.

Re:

[cmowire (254489)]

The mods to hit a non-manuvering target are probably not that bad. Besides, The Aegis / SM system is already being upgraded to knock out ballistic missiles. Plus, the test results there are much better than the results from the national missile defense system.

Both the original ASAT system and the Aegis are only useful for low orbiting targets. So it's probably more useful to have it as part of a theater defense setup more than something you need to have enough warning to launch an F-15 at.

But, yah, the s