Slashdot Mirror
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.'"
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.
todo - The developer's equivalent of confession: "Forgive me Father, for I have sinned..."
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?
Iraq billions
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.
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.
"When you sit with a nice girl for two hours, it seems like two minutes. When you sit on a hot stove for two minutes, it
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?"
THL phish sticks
And from TFA (again, emphasis mine):
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.
____
~ |rip/\/\aster /\/\onkey
Well, that's all well and good, but YOU read the fucking ARTICLE.
This space available.
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
Don't fear the penguins
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. 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.
The two shoot-downs are not equivalent, which of course won't prevent agenda-driven comparisons...
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.