US spy satellite re-entry

WASHINGTON (AP) -- A missile launched from a Navy ship struck a dying U.S. spy satellite passing 130 miles over the Pacific on Wednesday, the Pentagon said. It was not clear whether the operation succeeded in its main goal of destroying a tank aboard the satellite that carried a toxic fuel that U.S. officials said could pose a hazard to humans if it landed in a populated area.
 
Blowing it up wasn't an option either, it's not good practice to fly space missions with explosives, in fact, I doubt you are allowed to have a manned mission carry them, so it would have required a crew to be sent up to Mir, plus a 'Progress' module carrying the explosives, and that all costs money, so why spend a hundred million dollars to blow it up, when you can de-orbit it safely into the sea, for zero cost?
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I thought one last progress module was attached to deorbit the station.
Besides their are capable rockets today that can make a space hop (reach space but not orbit) Such a rocket could have destroyed mir and made in crash in any ocean at a very small cost
 
Asguard said:
hey try my post 5 mate
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There you suggest the US ask the Chinese to shoot it down. IMHO that is silly for main two reasons:

(1) China has nothing to gain and doing so is costly, very costly if they agreed and failed in their attempt. - They have demonstrated (announced after the fact) that they can hit an orbitor (but perhaps only when they get lucky as it is hard to do. I.e. perhaps their success was on try number 13 - a lucky number for the Chinese.) Hitting an exoatmospheric LEO orbitor is relatively easy compared to hitting one already being dynamically slowed by residual atmosphere as that acceleration is completely unpredictable.

(2) China probably hoped the US attempt would fail. From the Chinese POV it would be "great" if that the toxic gas fell on Paris etc. Thus as noted in point (1), China could only lose if it agreed. There was a slight chance that the US could be greatly embarrased by its space spy program. The Chinese could always hope for that, even it there was only 1% chance as they did not have anything to lose by doing nothing, and a huge cost / benefit ratio if they agreed. - Thus, silly to do so (or for US to expect them to agree and ask for help).

Also it would be very embarassing even asking for Chinese aid. Were you serious? or just kidding in post 5? I had assumed you were kidding /sarcastic in post 5, but after your post 86 I think your were serious!
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On anti ABM dificulties: Best (easiest) time to kill it is just as it is leaving the atmospheric forces, - very good idea if it is "MIRved," or has not yet deployed any decoys. It is also mainly still climbing and with hot skin from the air friction. This makes IR guidance easy also. Thirty miutes later it is cold, with decoys, etc - a much harder target. This is why "space-based" anti- ABMs were desired. (The APL/JHU designed Navy system is much cheaper and mobile.) I do not know any "secrete facts" but speculate that with spy satellite data US would know at least 10 days in advance of an ABM lunch - surely at least enough time to position an Aegis ship down track from launch towards contintial USA. Also the launch would be detected in seconds and confired in 30. Thus, the SM-3 could be on its way for a kill as soon as a spaced base system could in most cases.

PS to DH - the air force (and US army) can eat its heart out again. Especially the Army needs a captive lab full of brains, like APL. If they had run their Abrams "fighting vehicle" ideas thru APL we would have sued them - for the medical expenses of staff injured from excessive laughing. All the service need a high quality lab mainly because their own staff turnover is so high - typically about a year max in any one tour of duty technical assignment.* I bet the average APL technical staff averages 20+ years at APL, some have been there for 45+ or even 50 years in few cases. APL has been working for the Navy for about 75 years now.
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*All know you do not move up the command chain pushing a slide rule.
 
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draqon said:
yeah Billy T you are amazing, your bet won. the end.
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Also bet the launching ship was rolling +/_ 25 degrees at time of launch and 10% of the crew was "barfing" but SM system was designed to defend the ship in any weather the USSR could launch a sea-skimming cruse missle in.

later: Just heard on CNN (at 11:30AM ET) that 80 pieces are under track and "none is bigger than a foot ball"!
 
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Billy T said:
Also bet the launching ship was rolling +/_ 25 degrees at time of launch and 10% of the crew was "barfing" but SM system was designed to defend the ship in any weather the USSR could launch a sea-skimming cruse missle in.

later: Just heard on CNN (at 11:30AM ET) that 80 pieces are under track and "none is bigger than a foot ball"!
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oh I am sure the ship rolling isnt much of the problem, the missile is obviously coordinated based on a presumed flight path...any deviation and it alters its course to stay on the path it was destined to travel.
 
draqon said:
oh I am sure the ship rolling isnt much of the problem, the missile is obviously coordinated based on a presumed flight path...any deviation and it alters its course to stay on the path it was destined to travel.
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You missed the point. I said AT LAUNCH.

It ain't easy to get a long, thin, relatively light weight, "stick" out of a slightly larger square box that is rolling with the ship without snapping it in half. Was not even attempted on the first few AEGIS ships. - They still use above deck rail launchers, which to some extent can be stablized against the roll.

Yes in flight correction is easy. In fact even when the standard missle's target is a "sea-skimmer" it still launches "straight up" from the VLS. I am not sure (never worked in this area) but think that even if your target is straight over head, when the roll is extreme, may be good idea to launch near the extreme of the roll when the angular velocity is low. Probably timed so not to increase the roll amplitude.
 
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gawd...why they got to stabilize it at launch when the waves make things so chaotic? seems like too much hassle for me
 
draqon said:
gawd...why they got to stabilize it at launch when the waves make things so chaotic? seems like too much hassle for me
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Would you think it wiser to make it stiffer (more massive) and not have the required acceleration capabilies?
 
draqon said:
well Billy...I do have a solution, but...I can't tell you it
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As the SM defense was made for the old USSR, but they have now folded we don not need your solution. - problem it was designed for no longer exists. ;)
 
phlogistician said:
At a guess ABM is harder for a few reasons, one, the size of the target, this satellite was the size of a bus, apparently, speed, I guess ICBM's ar a tad faster, and location, they had the luxury of knowing the orbit of this object.

But it's all good practice.
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Well, speed wise it should be more or less the same.

Ballistic just means there are no outside forces acting on it, so it's basically a physics 1 problem---initial velocity, constant acceleration, calculate the position kind of thing. I find it very hard to believe that it's a different problem than shooting down a sattelite.

But the projectile size is probably the main issue. Even so, there's only a few factors of ten between a school bus and a warhead. It seems odd that, despite the amount of money that we through at the problem, we STILL can't get it to work.

On another note, China seems to be pissed. But I don't understand, because they basically did the same thing last year.
 
BenTheMan said:
Well, speed wise it should be more or less the same. ...
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A usual, Ben is nearly correct. The ABM can be a little bit slower than a LEO or significantly faster, if you are willing to spend the energy to put it highly eliptical orbit (Several Earth radii apogee and launch and target points on the ellipse.) That makes stopping it with anti-ABM missle very hard.
 
Ballistic missiles fly at suborbital velocities. They are moving slower than the 17,600 mph. Even ICBMs, which have an apogee of about 750 miles, have a top speed of about 15,700 mph.
Billy T said:
The ABM can be ... significantly faster, if you are willing to spend the energy to put it highly eliptical orbit (Several Earth radii apogee and launch and target points on the ellipse.)
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Except nobody does that. ICBMs have an apogee of 750 miles, not tens of thousands of miles. The Tsiolkovsky rocket equation tells us why.
 
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