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."

Good coverage

[BWJones]

Bruce is a fellow satellite spotter [utah.edu] also with some degree of background and in the subject matter and has good coverage here [and-still-i-persist.com].

Moon hiding behind megameters of solid rock

[isomeme]

Since that time interval occurs during daylight hours near Hawaii, with the eclipsed moon (necessarily) below the horizon, I doubt the eclipse will have much effect on visibility. :)

Re:How Convenient

[MutantEnemy]

I find your post a little hard to follow, however with regard to space debris, the satellite is sufficiently low that all the debris is expected to deorbit relatively quickly (days or weeks).

Just the facts.

[DerekLyons]

I doubt the lunar eclipse has anything to do with it. The timing is almost certainly based on the need to get the SBX [wikipedia.org] to sea and in position (it's not exactly a speedboat), and the best orbital conditions for the shot. The location was almost certainly based on the SBX being in Hawaii and having nice long empty stretches of ocean downrange for the SM-3 missile. (Both for the booster and for the payload to fall if it misses.)

Re:Good coverage

[T-Bone-T]

Interestingly, none of my AFROTC teachers would let us use FAS as a source in any of our briefings or papers because they only know just enough of what they shouldn't know to be dangerous.

Re:The Sorceror's Apprentice

[isomeme]

The thing's low enough that all of it -- intact or in pieces -- will deorbit soon (days to weeks). And actually, smaller debris deorbits faster; there's more surface area per volume (and hence per mass), so drag from the not-quite-vacuum of the upper atmosphere decelerates small pieces faster.

Re:Isn't it obvious?

[jonpublic]

obviously its just the government in a pissing contest with china.

its not like there are pesky differences between the two, like one was in high orbit, one is about to enter the atmosphere with toxic cargo and the potential to kill people if it lands in the wrong area.

Re:Good coverage

[RedWizzard]

They're not shooting at it to make it de-orbit, it's already de-orbiting. They are shooting at it to make sure that the hydrazine fuel tank doesn't make it down to Earth intact (or worse, almost intact).

Date confirmed

[daveschroeder]

...and the date has been confirmed [cnn.com]

Re:Good coverage

[SoapBox17]

It is also very important to note that the missile they are shooting it with does not have a warhead. They are basically just hitting it really hard, hoping to break it into pieces.

Re:Good coverage

[twiddlingbits]

Go look up Hydrazine (mono-methyl or di-methyl) and it's dangers. Tell ya what..heres the link to Wikipedia http://en.wikipedia.org/wiki/Monomethylhydrazine [wikipedia.org] and OSHA http://www.osha.gov/dts/chemicalsampling/data/CH_255500.html [osha.gov] Think about how dangerous it is and how much of it is onboard (50kg or so). Then think about how much a good ambulance chaser aka "personal injury" lawyer could make off said dangers by suing Boeing, the Government and who knows else if someone's land was "contaminated" and there was an "injury". Then get back to me about if $60M is expensive.

Re:How Convenient

[drerwk]

Actually, it doesn't. Orbital mechanics guarantee that the debris will pass through the same altitude one orbit later.

Re:Moon hiding behind megameters of solid rock

[Anonymous Coward]

At that point, the lunar eclipse hinders rather than helps things, by removing a light source.

Nope. Here's how it works:

1) a light source above the observer's horizon hinders visibility (can you see satellites when the Sun is up?)
2) a light source below the observer's horizon but above the satellite's horizon helps visibility.
3) a light source below both horizons doesn't do anything.

The eclipse reduces (1) compared to the full moon that would sit there otherwise, so it helps visibility by reducing a light source.

Gotta love the scores in this thread. The Dumbing Of America!

Re:Good coverage

[Guysmiley777]

As others have pointed out in previous slashdot commentaries, there's even the risk that the explosion might send pieces of debris upwards in the atmosphere, and it may even reach an altitude that will not allow it to fall back down for a very long time

Do some basic research and don't believe everything you read on Slashdot. The missile they are firing (an SM-3) does not have an explosive warhead at all.

N2H2: Weapon of Mass Destruction, or delicious?

[MillionthMonkey]

Actually, the classified hardware/software will burn up on reentry. Their more concerned about the full tank of hydrazine that would survive a normal reentry and create a hazardous materials nightmare near a populated area.

That's certainly believable if you can take Deputy National Security Advisor James Jeffrey at his word:

Yesterday, Deputy National Security Advisor James Jeffrey said the satellite's tank full of hydrazine rocket propellant was the main reason the military was planning to blast the orbiter. There's a small but real risk that the hydrazine tank could rupture, releasing a "toxic gas" over a "populated area," causing a "risk to human life."

Apparently man-made objects containing hydrazine propellant frequently rain down from the sky without incident, according to rocket scientists and space security experts [wired.com] who "scoff" at this rationale. And Joint Chiefs of Staff Vice Chairman Gen. James Cartwright doesn't seem too impressed either. But surely our Deputy National Security Advisor knows something about hydrazine that we don't.

Now who is this man James Jeffrey, you may ask?

It took more than two months, but the White House has finally found a new deputy national security adviser. And in the end, the administration didn't have to look very far.
President Bush will appoint Ambassador James Jeffrey, a high-level State Department official who coordinates its Iran policy, according to people familiar with the matter. Jeffrey's appointment will be made later today, these people said.
In his new post, Jeffrey will be National Security Adviser Steve Hadley's No. 2 and run most of the day-to-day operations of the National Security Council. The administration's new war czar, Deputy National Security Adviser Army Lt. Gen. Doug Lute, will take part in regular deputy's meetings chaired by Jeffrey.
Jeffrey, a blunt-spoken and often-profane diplomat, will replace J.D. Crouch, an architect of the administration's controversial Iraq surge who resigned in May. Jeffrey has spent more time in Iraq than any other senior administration official. Prior to assuming his State Department post, he was the deputy chief of mission at the U.S. Embassy in Baghdad from June 2004 to March 2005, and as U.S. charge d'affaires to Iraq from March to June 2005.
A colleague of Jeffrey's said that the White House would likely prove to be a better fit than the State Department had been. The colleague noted that Jeffrey is a staunch neoconservative, which left him often sharply at odds with other high-level State Department officials. Most of the neocons who once populated the administration left their posts in recent years as the Iraq war went off the skids. At the White House, though, Jeffrey will be able to work closely with two of the other surviving neocons: Deputy National Security Adviser Elliot Abrams and David Wurmser, one of Vice President Dick Cheney's top foreign policy staffers.

Source: Wall Street Journal, [wsj.com] July 19, 2007, four months before the information in the Iran NIE would be exposed, having been known to the White House since 2006.

This guy sounds totally not full of shit at all!

Re:Good coverage

[KarMann]

Actually, the final target tracking is most likely done either optically or by infrared. But, as I mentioned below, the area is in broad daylight at that time, and the Moon is below the horizon, so you're still quite correct to doubt that the Moon would interfere in any way.

Re:Good coverage

[93 Escort Wagon]

The *real* reason that they're spending $60M is to make sure that some fuel doesn't contaminate an acre or so of land.

      Hey, each shot is only 60% of the National Science Foundation's annual budget. Why not?

The NSF's 2008 budget request is for 6.43 billion dollars [nsf.gov]. But hey, what's a few orders of magnitude between friends?

Re:10 bucks

[plover]

Two-Line Elements

USA 193 5.0 2.5 0.0 4.3 v 20 256 x 250 km
1 29651U 06057A 08049.90355339 .00233341 23303-4 27965-3 0 90004
2 29651 58.5130 35.7739 0005018 100.5255 259.5312 16.07731429 145

You don't have to pay me, of course, especially since slashdot screws up the spacing making them useless for copy/paste. I pulled them from this page [calsky.com] by clicking on the little Orbital Elements (TLE) button.

Re:Good coverage

[everphilski]

Now, instead of one big vaguely predictable chunk of technology falling down, we're going to have hundreds if not thousands of smaller chunks that are going to be absolutely impossible to predict their trajectory.

As someone whose day job is re-entry of large objects from near-orbital velocities I feel pretty qualified to respond to this. "vaguely predictable" is pretty generous. For the upper stage of a launch vehicle re-entering under an hour after launch (read: we know precisely where it is coming from, have the trajectory modeled, etc), there are thousands of miles in the "footprint" of the debris. And while most of it will come down in one or several big chunks, there will be a lot of scatter debris over that footprint. Now, think of something that's been in orbit for a number of years. Sure, we can observe it for a few months and try and nail the orbital parameters, but any way you slice it, it's an uncontrolled re-entry. We don't know with high precision the injection orientation, velocity, orientation, etc. That baby could have an uncertainty of 10,000 miles or more on it's footprint.

Also another note: big, dense, heavy things tend to break up very little on re-entry. They soak a lot of heat and come down hard and heavy. Big, light things like expended stages tear apart into little pieces and essentially dissipate in the atmosphere, leaving very little debris. And what debris remains, slows down very quickly, reducing scatter versus heavy pieces that just keep on flying. So there is a distinct advantage to breaking this thing into pieces. It will tear itself to shreds, versus coming down like a rock.

there's even the risk that the explosion might send pieces of debris upwards in the atmosphere, and it may even reach an altitude that will not allow it to fall back down for a very long time.

Don't believe everything you read on slashdot. What goes up must come down. The only way it will stay in orbit is if you give it the appropriate energy tangential to the surface of the earth to sustain an orbit, or more. That's it. I could shoot a bullet up into the sky right now at M=10,000, and it's either escaping the gravitational grasp of the earth or coming back to hit it. The chances of random pieces entering a stable orbit for the long term is slim. The chance of a few random pieces extending their stay? Granted, maybe for a few months to a year.

Re:Nothing to see here, move along

[TapeCutter]

The reactors sent into orbit are supposedly built to withstand re-entry and a crash landing. Firing explosives at a reator in LEO and potentially spreading fairy dust everywhere is probably worse than letting it form a crater in the ground where contamination can be contained.

Regardless of the 'real reason', shooting down the hydrazine is a GoodThing(TM).

Re:How Convenient

[ceoyoyo]

Spy satellites (or any imaging/mapping sats) are usually in very circular orbits. Otherwise your image resolution gets degraded for most of the orbit (because you're farther away) and you have to constantly keep track to figure out what the actual resolution IS. As you pointed out, atmospheric drag tends to circularize things as well.

Re:Good coverage

[Planesdragon]

AHHHHHHH!!!

I assume that anyone who can put a satellite into a stable orbit can also kill a foreign satellite. That may or may not be naive,

It is. Anyone who can fire a bullet cannot necessarily hit someone else's bullet out of the sky. (And there's no such thing as a "stable" orbit for most satellites, but that's neither here nor there.)

but it doesn't matter: Shooting at a foreign satellite is an act of war. When you do that and thereby start a war, the time of spy satellites is over anyway. The only options are not to shoot, for which you don't need the capability, or to shoot, and then the spy satellite is the least of your worries.

Spy satellites are at their most useful in a time of war. As are GPS satellites, which are used in a modern weapon system called a "JDAM", which is largely responsible for the high-precision warfare the US enjoys now.

In the event of a US-China War, expect China to shoot down GPS satellites before they even worry about air supremacy. And expect the US to launch them at a record pace.

Re:Nothing to see here, move along

[Rei]

At least they never dared launch anything as crazy as Starfish Prime [wikipedia.org].

We are not the immaculate custodians of space that you seem to be picturing. Why, do you think, did we not shoot down the Delta II second stage that reentered in 1997 with a large amount of residual hydrazine and nitrogen tetroxide onboard? We have stages with signficant amounts of toxic residual fuel reenter all the time. Why, in the same year, when we had a Delta II explode *full* on liftoff, did the Air Force tell people in the *immediate area* that the smoke posed no danger? This was a *full launch vehicle*, not just a satellite's orbital maneuvering system. Do you have any idea how much beryllium we've had reenter? We sit by as large amounts of toxic materials enter all the time. As for the hydrazine itself, what do you think happens *on its own* to pressurized tanks of highly flammable fluids on reentry? I can't think of a *single* sizable object that's survived reentry still pressuretight.

The argument is completely bogus.

Re:Nothing to see here, move along

[Rei]

It doesn't work that way. Nothing manmade reenters all in one place and leaves a "crater". Debris generally gets scattered along a trail across a thousand miles or two in chunks.

Re:Good coverage

[BillyBlaze]

Actually, I heard a pretty argument that no debris produced by this could stay up for more than a few orbits. Basically, no matter what impulse you give to something at a certain point in its orbit, the new orbit and the old orbit will have that point in common. And that point is low enough in the atmosphere that any orbit crossing it will decay quickly.

In other words, the best you would get is a highly elliptical orbit that still crosses through the point of the explosion, but it will be circularized by the atmosphere. If a piece of debris is shot "upwards", than it will actually be in an orbit that includes an even lower point. That is, if it's moving upwards from the point, then during its next orbit, it will necessarily be below the point.

Re:How Convenient

[BillyBlaze]

Well spirals are orbits, but ones which are perturbed by air resistance. If you ignore air resistance (and relativistic effects), then yes, all orbits would be perfect ellipses (or hyperbolas). In this case, the orbits of any debris will pass through the point of the explosion again, discounting air resistance. In reality, they will pass even lower, due to air (and in many cases, ground) resistance. They only way they could attain a stable (that is, higher than significant air resistance) orbit is if half an orbit after the explosion, they get kicked forward again.

Re:Just the facts.

[BenBenBen]

The SBX has been in Hawaii being repaired [blogspot.com], as it's a huge turd in seagoing terms [blogspot.com]. Can't cope with 8ft seas, and has no launch capability (as in, if you fall overboard you better start swimming, they ain't gonna pick you up).

Re:Nothing to see here, move along

[deKernel]

First off, the US has NEVER claimed to be the "...immaculate custodians of space..." like you claim.
Second off, regarding the Delta II second stage, it was believed based upon its size, speed, trajectory and form that it would burn up on reentry so the belief was we were OK. We know for sure that the satellite will survive reentry so we are trying to be proactive.

Do we allow toxic material to reenter, Yes. Do we believe based upon size, speed, trajectory and such that the material will burn up, Yes. Can we send up a missile on everything that is reentering our atmosphere, No. At least we are trying (for whatever reason you want to believe) as compared to other nations so please take off the tin foil hat so your head can get a little air in hopes it allows you to think just that much more clearer.

Re:Self-destruct - standard feature

[chihowa]

...why not build satellites with standard self-destruct for cases like this?

First, a self destruct mechanism would add mass to the satellite, which takes mass away from other gear you'd like to add.

Secondly, if your satellite is not functioning, like this one, how would you activate the self-destruct mechanism?*

A possible third is security. What if "the enemy" were to get a hold of the self-destruct codes for all of our satellites? Shooting down a satellite with a missile is a much more costly and traceable event than sending out a radio signal and quietly killing them as they pass overhead.

*I can think of ways to do this, with pressure and temperature sensors to detect a decayed orbit or an entirely redundant receiver and power supply, but you're really adding mass here. For the extra mass to launch or the reduced capability of the satellite, it may be cheaper to just shoot down birds that don't work.

Re:Good coverage

[rahvin112]

Nothing useful in terms of spy gear is going to make it through re-entry. What might make it through re-entry is a large, resilient fuel tank containing high-toxic, probably carcinogenic, fuel. Logic dictates that if there was really something classified on the satellite that they didn't want to survive re-entry they simply would have designed it to not survive re-entry or they would have installed a self-destruct. Shooting it down at this point for the reason you're implying doesn't make sense.

Besides, if it's the gear (rather than the fuel) that concerns them then why haven't they bothered shooting down other de-orbiting sats in the past?

Your logic is faulty. In a controlled reentry they would have positioned the satellite to land in the deepest water in the pacific they could reasonably hit thereby eliminating any sensitive information or equipment, not only that but decommissioning the bird would have been well after it's reasonable lifetime and the on board equipment would no longer be as unique. In addition the solar panels never deployed and are still wrapped around the bird. They would likely shield the bird for a portion of the reentry thereby greatly increasing the odds that more than the hydrazine tank will survive reentry, whereas in a controlled reentry the panels would be deployed and would break off and reenter separately.

Shooting this thing down 7 days before it reenters is for one purpose only. There is something on the satellite they don't want landing. You could argue the Hydrazine is the problem, my personal belief is they have calculated the reentry point and believe it's going to land in a nation that isn't an ally. This satellite also contains certain sensors or equipment that will at least partially survive reentry and that even if only a small piece of such equipment survives the very presence of it on the satellite will alert other nations about what technology is being used. I also believe this technology is either highly unique or it's application is something no one would think of until seen in operation. Given that the age of this spy satellite is only 2 years old it's almost certain that the nations most high tech spy gear is on board. There is also the secondary possibility that it contains weapons that would implicate the US in violation of the international militarization of space treaty.

IMO the hydrazine is just a cover for the real problem, there is something else on that bird (that they aren't talking about) such that knowledge of it's existence is perceived by the administration as a serious threat to the US.