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USA 193 Shootdown Set For Feb 21, 03:30 UTC
An anonymous reader writes "Amateur satellite watcher Ted Molczan notes that a "Notice to Airmen" (NOTAM) has been issued announcing restricted airspace for February 21, between 02:30 and 05:00 UTC, in a region near Hawaii. Stricken satellite USA 193, which the US has announced plans to shoot down, will pass over this area at about 03:30. Interestingly, this is during the totality of Wednesday's lunar eclipse, which may or may not make debris easier to observe."
While perhaps a bit unconventional, there's a lot to be said for our government's decisive action here that could prevent a small-scale disaster if the satellite were to hit the ground. It seems like the prudent thing to do.
*cough*THEL*cough*
An airplane needs an engine to fly, and when that engine is destroyed and crashes somewhere near where you shot it down. A satellite needs no engine to fly, and when you shoot at it, it becomes thousands of little satellites, all of which continue to "fly" at 25,000 miles per hour.
I hope the people shooting at (not "down") this satellite have seen "Fantasia." In _The Sorceror's Apprentice,_ Mickey Mouse decides that the best way to deal with an out-of-control magic broom is to chop it into thousands of pieces... all of which just keep right on going, making the problem worse instead of better.
"How to Do Nothing," kids activities, back in print!
FAS always raises hell over weapons tests of any kind. What else is new.
The SM-2 to be used is actually being MODIFIED with new software to try to do the intercept. It's not certain it'll work. So I guess that makes it a test.
The eclipse likely makes it easier to spot the "target".
But at least we aren't leaving a shitload of crap to fuck up usuable orbit space like the ChiComms did in their ASAT test. This bird is coming down NOW so why not test on it. It's cheap, if it works maybe we have a new use for an existing system w/o spending millions, we clean up our own mess by shooting it down, the debris will come down (with some risk as it's smaller pieces) and not clutter the crap out of orbital space, and we trash anything secret the enemy might try to capture (assuming it survived re-entry..but why risk it?). Sounds like a bargin "test" to me.
The satellite is being blown up because its about to crash into the planet. Why do you suppose the debris will stay up any longer?
I'd expect that shooting a satellite whose orbit is already decaying might hasten the process by a couple days (smaller pieces would generally have a lower ballistic coefficient and therefore decay faster), but not by a significant amount.
The real benefit (to the US) is that turning a big, expensive satellite with lots of classified equipment on board into a bunch of little satellites means that the expensive bits are rendered unusable and far less likely to get to the ground intact, where they can be analyzed. It also provides a good opportunity to test a new missile system, and shows the Chinese that the US can play at their game, too.
The meek may inherit the earth, but the strong shall take the stars.
Well, there may be some truth to it. But like most decisions, there are a lot of things at work here:
1. Having a giant hydrazine tank land on someone's house would be a PR nightmare.
2. Having a spy satellite presumably filled with highly-classified stuff fall into the wrong hands is something They(tm) try to avoid.
3. Demonstrating to the rest of the world that we can blow their satellites into much less useful pieces is somewhat in line with the agenda of the Bush administration.
4. It can also be pointed to as a success of the missile defense program.
So I wouldn't write off the whole hydrazine tank issue entirely, but I doubt its the primary motivator.
No doubt goats will be slaughtered, wiccans consulted, and pentagrams drawn all in the hope that our missile intercept technology will actually work in a non-staged event.
And if it works? What then? How many successful test intercepts do you need before you think that the thing might actually work? Seriously, the only reason some folks are arguing that they don't think missile defense can work is because they do not like the politics of it. Eventually, missile defense can and will work. It's just an engineering problem, after all.
I for one do not think the USA should be deploying interceptors in Poland to antagonize the Russians, but, I've got no problem with spending a bunch of billions a year to give the USA a unique capability in a world where every country is working to develop ICBMs.
This is my sig.
Along the lines of the self-destruct, I agree that a satellite which absolutely could not be allowed to return to Earth intact would be built with the proper destructive methods.
However, a self-destruct would also be useful in cases just like this, where the danger is not classified information, but hazardous materials. I am assuming that satellites are usually launched with the anticipation of decaying orbits, so why not build satellites with standard self-destruct for cases like this?
It seems like a relatively common occurrence (Skylab, anyone?) and seems like it would be a lot less expensive and require less logistical planning than having to time a missile interception.
I think this hydrazine thing is a red-herring. Think about it for a minute. So they say it's frozen, and in a really strong tank. But once that tank starts re-entering, the valves and hoses to it will be torn free. The heat of re-entry is going to unfreeze at least part of it. Now you've got venting ROCKET FUEL in the heat of a re-entry. I say at that point, the tank goes BOOM and there is nothing left... I think the real reason we are shooting this bird down is that it was launched in 2006 and has all our latest cool spy gadgets on it. We don't want them in an enemy's hands. So they cooked up this whole "hydrazine" problem to make it look like they are doing the world a favor. And they probably are. But I don't think its the hydrazine that is the problem here...
Brawndo: It's what plants crave!
Not...
This is simply an excuse to play tit-for-tat w/the Chinese over their all ready having demonstrated alacrity at blowing sats out of the ionosphere.
I had a chat with my grandfather who works on attitude control systems for commercial satellites about hydrazine. Hydrazine is used for attitude control and orbit stabilization. Since contact was never made with this USA 193, the hydrazine tank should be full. The ignition for hydrazine is heat, so all they do to fire it is have a little toaster that ignites a little bit of fuel at a time. Because the ignition source is heat, the hydrazine tank has to be incredibly well insulated to maintain a constant temperature. If the tank were to survive reentry, by being shielded by other components melting off, it would most likely rupture when it hit the ground at terminal velocity. Hydrazine is a pretty serious hazmat, and even a small concentration of that into your system will do serious, potentially permanent or even fatal damage to your lungs. Even worse, the hydrazine could ignite upon hitting the Earth and cause a small explosion, though the gas leak is more likely. If you took the surface of the earth and divided it into 1 acre chunks, I doubt more than 5% of those acres would have people in them( figure 10% of the Earth is inhabited, and large portions of that are farm) Nevertheless, a 1/20 chance of killing/permanently damaging anywhere from 1(hits near Bear Grylls in the desert) to 10,000 people(hits Rio), it certainly seems like a politically influenced decision to get rid of a potential disaster.
Well... This is one of those cases where there 'scientists' and 'experts' only tell half the truth - the half that supports an anti-Administration agenda. The other half of the truth is... all the cases they cite have roughly zip point nada in common with USA-193. In those cases, the tanks are empty or nearly so. In the case of USA-193, the tank is not only full - but frozen solid. The chances of it surviving re-entry intact or nearly so are much greater than previous incidents.
Insofar as the cost issue goes - it's pretty much a wash. Spend the money on the next test against a drone, or spend it on a test against USA-193.
The REAL fun begins when the headlines on the day after read : "Shoot down of satellite failed."
(unlikely, but not impossible...)
If there is one thing to be learned on slashdot, it has to be sarcasm.