NASA: Satellite Debris Probably Hit Pacific, But Room For Doubt

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NASA: Satellite Debris Probably Hit Pacific, But Room For Doubt

Posted by timothy on Saturday September 24, 2011 @07:07PM from the bring-your-finest-metal-detector dept.

An earlier report that debris from the recently deorbited UARS satellite had landed in Canada may have been premature. Apparently, the picture of when (and therefore where) the satellite deorbited is back to being clear as mud. Most likely, says NASA, the debris will never be found, but is thought to have landed in the Pacific Ocean. If you're an optimist interested in finding your very own piece of space debris, though, you might be interested in this map based on various re-entry scenarios (hat tip to Robert Woodcock); in the U.S., the Northwest is your best bet.

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A clue to the location by Anonymous Coward · 2011-09-24 19:28 · Score: 3, Funny

A whale with a serious headache thinks he knows where it came down.
1. Re:A clue to the location by Anonymous Coward · 2011-09-24 21:39 · Score: 3, Funny
  
  Hole-in-one, eh?
Re:Northwesterner by davester666 · 2011-09-24 19:38 · Score: 1

It's just a flesh wound!

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Move along by Anonymous Coward · 2011-09-24 20:01 · Score: 2, Funny

Nothing to worry ab
Wrong planet. by ozmanjusri · 2011-09-24 20:43 · Score: 1, Offtopic

Such a shame Schrödinger's crater is on the moon.

--
"I've got more toys than Teruhisa Kitahara."
1. Re:Wrong planet. by lennier · 2011-09-25 09:57 · Score: 1
  
  Well, it is and it isn't.
  
  --
  You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC
A little confused... by SomePgmr · 2011-09-24 20:52 · Score: 1

From what I understand, UARS was intentionally decommissioned and was instructed to perform a burn to (eventually) bring it down. But for the last few weeks we've had what appears to be zero useful clue about where it might land. I mean, speculations included at least 3 different continents and two oceans in a window of something like 12 hours, as recently as a couple days ago.

Don't we have more deliberate and controlled ways to de-orbit satellites? Or is it just too complicated and expensive to add that kind of functionality considering the extreme odds of actually hitting anything valuable?
1. Re:A little confused... by jhoegl · 2011-09-24 21:00 · Score: 1
  
  Yeah, I was thinking that too.
  
  It almost seems hyped, but the media would never do that, right?
2. Re:A little confused... by dutchwhizzman · 2011-09-24 21:10 · Score: 4, Informative
  
  From what I understand, they usually use the last fuel to put it into a clear and controlled descending orbit. For some reason, I think they ran out of fuel before they could do that on this particular satellite.
  
  --
  I was promised a flying car. Where is my flying car?
3. Re:A little confused... by dbIII · 2011-09-24 21:13 · Score: 1
  
  It takes fuel to slow down with precision just as it does to speed up, and there wasn't any fuel. They call it "delta V" (change in velocity) for a reason instead of just talking in terms of velocity increases. Without fuel there's nothing to punch it through the atmosphere to a certain area instead of it skipping about those few degrees that make a difference between landing in Canada or the Indian Ocean.
4. Re:A little confused... by ygslash · 2011-09-24 21:30 · Score: 5, Informative
  
  From what I understand, UARS was intentionally decommissioned and was instructed to perform a burn to (eventually) bring it down.
  Yes. When it was decommissioned several years ago, it used its last bit of fuel to bring it to a lower orbit so that it would come sooner.
  
  Don't we have more deliberate and controlled ways to de-orbit satellites?
  Yes. Nowadays, that is part of the mission planning for satellites. (Well, at least for NASA satellites...)
  
  Or is it just too complicated and expensive to add that kind of functionality considering the extreme odds of actually hitting anything valuable?
  That was the thinking in days when UARS was launched.
  Nowadays, even that tiny risk is considered important enough to justify controlled de-orbiting. Mainly for PR reasons, I think.
  In addition, we now realize that leaving dead satellites hanging around in a low orbit for a few years runs the additional risk of it colliding with something and causing an explosion of space junk.
5. Re:A little confused... by hairyfeet · 2011-09-24 22:19 · Score: 2, Interesting
  
  What I don't get is why we try to bring them down when they are already in space. wouldn't the smarter move be to just point them outwards and tell them to burn until they run out of gas. After all it IS space we are talking about here, one big black empty pile of nothing.
  I mean if you didn't want the drifting through the cosmos for some reason you got a big fireball in the center and Jupiter the other way to aim at, but in the end who cares as long as it is away from us right? It seems better than polluting the Pacific with space crap constantly.
  Of course the BIG problem is gonna be cleaning up all the little pieces of dead shit along with dead birds we have polluting everywhere. From what i've read all the little pieces of metal, paint chips, dead birds, boosters, and all the other assorted crap is damned near reaching critical levels for the good orbits. We are really gonna have to get together as a planet and work out a way to clean that mess up! Did you know the Vanguard sat we put up there in 1958 is STILL up there? it is amazing how much garbage there is between the USA, Russians, and of course them dumbass Chinese blowing that one up and making a huge fucking mess.
  If we don't clean that mess up soon frankly it isn't gonna matter where we WANT to de-orbit birds to, as they are gonna get so trashed that we'll lose control of them long before their life was up anyway.
  
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6. Re:A little confused... by Anonymous Coward · 2011-09-24 22:44 · Score: 5, Informative
  
  It takes a LOT of fuel to break orbit. To little and it will come back eventually. Why waste a buttload of fuel to lift all that extra fuel into orbit just so the satellite has enough fuel left so it can break orbit. It's much easier and cheaper to deorbit by bringing it down and letting gravity do the work.
7. Re:A little confused... by edxwelch · 2011-09-25 01:10 · Score: 1
  
  > Nowadays, even that tiny risk is considered important enough to justify controlled de-orbiting. Mainly for PR reasons, I think.
  Hmm, tiny risk, but serious consequences. A large satellite piece landing in the center of a city is going to cause a lot of damage.
8. Re:A little confused... by izomiac · 2011-09-25 02:32 · Score: 5, Informative
  
  Gravity at Earth's surface: 9.8 m/s^2
  Gravity at ISS: 9.1 m/s^2
  
  Satellites are still very much inside Earth's gravity well. They are not floating in space, they are constantly falling but their tangential velocity ensures they miss hitting the Earth.
9. Re:A little confused... by eyenot · 2011-09-25 04:20 · Score: 1
  
  This is a great comment, BTW. I love how many times you say "dead birds". I'm not sure but I think you're saying that there are dead birds littering up outer space. Is that true? That's fucking atrocious! How the hell are they getting up there?!!?!?!?!?
  
  --
  "Stratigraphically the origin of agriculture and thermonuclear destruction will appear essentially simultaneous" -- Lee
10. Re:A little confused... by khallow · 2011-09-25 06:21 · Score: 1
  
  A large satellite piece landing in the center of a city is going to cause a lot of damage.
  An out of control car probably will do more damage. It's worth keeping in mind that even the large satellite pieces tend to be very fluffy. They might weigh hundreds of pounds, but they'll be coming down rather slowly.
11. Re:A little confused... by Urkki · 2011-09-25 06:48 · Score: 1
  
  It's much easier and cheaper to deorbit by bringing it down and letting gravity do the work.
  Nitpick: letting air resistance do the work.
  With a bit of twisted thinking, gravity is actually the problem here! It's what keeps dead satellites in orbit, instead of letting them harmlessly escape into deep space.
12. Re:A little confused... by izomiac · 2011-09-25 07:06 · Score: 1
  
  Ah yes, the Icarus birds. A tragic species, they often fly too high until the atmosphere is thin enough they asphyxiate. Thus, despite being able to fly twenty times faster than a peregrine falcon, they are in constant danger of extinction.
13. Re:A little confused... by sznupi · 2011-09-25 07:08 · Score: 1
  
  Not really. For a large piece - think a big piano, or (unavoidable analogy) a car, or maybe a loaded van being dropped from an aircraft at altitude (debris essentially falls at its terminal velocity when hitting surface). Yes, the day will suck for anything or anybody directly hit, or in the immediate vicinity; there's also a slight possibility of toxic propellants or such surviving the reentry. But I wouldn't really count it among "cause a lot of damage" even within city centres; don't expect anything really worse than a bad road accident (those even sometimes involve toxic substances; though, admittedly, such are unlikely in city centres) or not particularly newsworthy building fire / gas explosion.
  
  It probably seems more scary than it is because of how bad our primate minds are at assessing risk, statistics (go through a list of cognitive biases; this is our primary mode of operation). Road accidents and overall automotive safety are examples of that, too - with them, we also greatly value what merely feels safe (even if, in reality, stats are against it), what gives an illusion of control (say, by sitting higher than others)
  
  Severe lack of such illusion is probably why sat debris (generally, sudden attack from above) is so scary, why we want so much to know where it will hit.
  
  Kinda how Zeus and his lightings are scary.
  
  --
  One that hath name thou can not otter
14. Re:A little confused... by lennier · 2011-09-25 10:04 · Score: 1
  
  Kinda how Zeus and his lightings are scary.
  Tell me about it. Stock standard recessed downlights with high-K fluorescent bulbs? Utterly pedestrian, darling. Get Athena to whip you up some kind of LED chandelier, she's good with the tech stuff.
  
  --
  You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC
15. Re:A little confused... by hairyfeet · 2011-09-25 15:48 · Score: 1
  
  What happened to the whole "rock skipping off a pond' thing we heard about like a bazillion times when NASA had a ship coming in? could you just use that to skip the sucker right on out of here? i know we use gravity assists to gain speed for long missions, why not use that on the birds before they run out of gas?
  It STILL seems like a better idea to me that dumping ton after ton into the Pacific, especially with all the toxic crap that can be in some of those sats. We really shouldn't use the ocean as a garbage dump, i don't care how big the thing is. its that kind of thinking that has that huge floating garbage pile in the pacific right now.
  
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  ACs don't waste your time replying, your posts are never seen by me.
16. Re:A little confused... by izomiac · 2011-09-25 16:19 · Score: 1
  
  To escape a gravity well you need a certain amount of energy per mass. On Earth's surface, it's 60MJ/kg. When you get to orbit you are a bit further away (gravitational pull declines asymptotically) so you only need 57 MJ/kg. That's what you need to get out of the hole. This is conservation of Energy, so there are no cheats to get around it. Otherwise we could deorbit and reorbit objects for free energy. Satellites would need to carry twenty times more fuel to deorbit.
17. Re:A little confused... by Askmum · 2011-09-25 21:52 · Score: 1
  
  UARS made one orbit in less than 90 minutes, so if the de-orbit accuracy is 12 hours, then you have no clue at all where it will actually come down.
  
  It came down on its own, no assistance from de-orbit burns, the only thing stopping it was the drag from out atmosphere. And that tends to expand and contract rather erraticly due to external influences (like the sun) so it is very very very difficult to say when it would come down. Even in the last 8 hours the predictions of when it would come down were accurate only to more than 1 hour, so still more than half the earth covered.
  
  At the time when this satellite was launched, there wasn't a big concern about them coming down (or better: what happened after decommissioning). Now there is. These days, satellites are planned to have some fuel left to make a controlled de-orbit or move it to an orbit so it won't come down.
18. Re:A little confused... by hairyfeet · 2011-09-26 03:01 · Score: 1
  
  But I'm not talking about free energy, I'm talking about using the energy of the earth to slingshot it out. Just like being on the end of a spinning whip you use the gravity of a partial fall to give you momentum followed by a burn out, like going downhill to pick up speed followed by gunning it to shoot up a hill.
  Meh I think our entire system when it comes to sats is dumb anyway. I mean here we are still using the tech they used when Von Braun was lobbying V2s at London. I think Gerald Bull's idea was the way to go, the supergun, only he didn't have the correct technology at the time. Instead of explosives you use a coil gun mounted on the side of a mountain, maybe one of those we've kept since taking them from the Japanese in WWII? You would have a long flat straightaway followed by a curve up the mountain and use a nuclear plant for power.
  If one wanted to have it man rated the straightaway would have to be huge to keep the g forces from hitting too hard but for dumb cargo and sats I bet it would work just fine, and because you would only need to fire your rockets at the very top of the arc one could save a hell of a lot of fuel which could then be used not only for extending the maneuvering life of the sat but still give it ample fuel to get rid of it when it was EOL.
  Ultimately if we are ever gonna get off this rock we'll have to find a new way to do it such as the supergun, because chemical rockets simply take too much fuel for too little payload. If one used the supergun with a modular design one could send the rocket up in stage and put it together in space and fly it out from there.
  Either way just dumping tons of crap in the pacific still seems like a BAD idea. We can't just keep using the ocean as our personal garbage dump without it eventually coming back to bite us in the ass. Hell maybe we should be looking at smaller and cheaper modular designs that could just burn up on the way down, who knows. I just know we humans seem to be lousy at looking at the long term, which is how we ended up with so much dead crap in orbit in the first place.
  
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  ACs don't waste your time replying, your posts are never seen by me.
19. Re:A little confused... by izomiac · 2011-09-26 14:38 · Score: 1
  
  But I'm not talking about free energy, I'm talking about using the energy of the earth to slingshot it out. Just like being on the end of a spinning whip you use the gravity of a partial fall to give you momentum followed by a burn out, like going downhill to pick up speed followed by gunning it to shoot up a hill.
  What you're trying to do is increase an object's gravitational potential energy without expending any significant amount of chemical potential energy or kinetic energy. This is not consistent with the law of conservation of energy. It would be akin to getting a 100 lbs dumbbell on your roof without lifting it.
  
  Here are some formulas. (M1 = mass of the Earth, M2 = mass of the satellite, r = altitude from center of Earth, v = speed of satellite, G = gravitational constant)
  
  Gravitational potential energy = U = -G * M1 * M2 / r
  Kinetic Energy = K = 1/2 * M2 * v^2
  Chemical potential energy is going to equal what your fuel can give you (C)
  
  So, you're trying to increase U from -57 MJ per kg of satellite to 0, while maintaining a non-zero K (insignificant compared to energy for U), and having almost no C to compensate. For comparison, think of a 1 kg iron ball released with a velocity of 1 m/s pointed toward the Earth from an incredible distance. When it hit the atmosphere it'd have nearly 60 MJ of energy from the conversion of the gravitational potential energy (0 to -60 MJ) into kinetic, so it's velocity would be about 11.4 km/sec. But the satellite doesn't have that much kinetic energy (and heck, the tangential velocity is the only thing that keeps it from falling toward the Earth in the same manner, so it's not exactly expendable).
  
  Gravitational slingshots work in cases where a planet is moving relative to the spacecraft and the spacecraft gains twice the difference in velocity by slowing down the planet. The Earth is not moving relative to an orbiting satellite, so this technique will not help you.
  
  If you really wanted to deorbit a satellite you'd need to supply energy. I suppose a sufficiently powerful laser could vaporize the Earth-facing side and the escaping gas might work to propel the satellite to a higher orbit, but I suspect it'd be completely vaporized (with the molecules still orbiting the Earth) long before it deorbited. But this is a risky procedure, as you'd probably just put the thing into some kind of crazy spin (think failed rocket launch) and create a ton of orbital debris.
  
  All of these concepts tend to be covered in college level physics, so if this topic interests you I'd highly suggest checking it out. You obviously have been paying a lot of attention to the space program, but you've reached the level where you need to have a bit of a physics background to go much father. If we could deorbit satellites like you suggest that would be a great idea, but the laws of physics don't allow it. So, knock yourself out, gravity is covered very early in modern physics books (or free web resources), so it's not much of a time investment, and the non-Calculus based versions should make it easy to pick up even without a strong math background.
20. Re:A little confused... by Coren22 · 2011-09-27 03:34 · Score: 1
  
  When you see her, tell her to give me a call, I miss talking to Athena.
  -Hephaestus
  
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Hmm... by Ecuador · 2011-09-24 21:43 · Score: 1

So, nobody seems to be able to track the planned reentry of a big satellite in 2011...
I guess then it is not too probable that governments have been tracking alien FTL spaceship visits since the 1940's, is it? ;)

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1. Re:Hmm... by RogerWilco · 2011-09-24 21:53 · Score: 1
  
  What do you think all those neutrino detectors were being built for? It's how you track those FTL ships. Only the military didn't think the CERN people would figure it out as well.
  
  --
  RogerWilco the Adventurous Janitor
2. Re:Hmm... by Nyeerrmm · 2011-09-25 05:20 · Score: 1
  
  Well, to be fair, a satellite in an extremely low Earth orbit with significant drag throughout its entire orbit is probably the most difficult place for us to track a live satellite.
  The atmosphere is unpredictable, so its constantly rephasing the orbit in ways you can't predict, and when its that low, a ground station has a very brief time to get acquisition, get some data, and send it to the controllers for orbit determination. Compare to a deep space vehicle (say Juno instead of an alien spaceship), where even if you're uncertain by 100s of km you're still within the beam-width of a DSN tracking station, and you only need three stations around the globe to track it at any point in time. Plus the orbital dynamics are known well enough that you should be able to find it again 6 months or a year later pretty easily even if you lose all tracking data from now till then.
If there was something important or secret onboard by PolygamousRanchKid+ · 2011-09-24 22:18 · Score: 1

. . . would NASA really tell us where it landed, or would they want to recover it themselves?
Mulder & Scully: "Where did the satellite land?"
NASA: "Um . . . like . . . in the Himalayas, or somewhere . . . I dunno . . ."
Hmmm . . . maybe I need to make a quick trip to Ice Station Zebra and snoop around . . .
But if it really was a super secret squirrel satellite . . . we probably wouldn't have even known that it was coming down.

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A few people in Canada saw it... by Evil.Bonsai · 2011-09-24 23:21 · Score: 1

http://youtu.be/2OfWgu5jk5g
1. Re:A few people in Canada saw it... by Anonymous Coward · 2011-09-25 01:20 · Score: 1
  
  That video does NOT show UARS. It is footage of a series of Chinese lantern balloons. There is more of this deceptive stuff floating around on the internet - not every light in the sky is UARS!
2. Re:A few people in Canada saw it... by Anonymous Coward · 2011-09-25 01:52 · Score: 1
  
  That's a hoax upload, even the guy in the video said the wrong location and date.
  Read the comment from this other video for details:
  http://www.youtube.com/watch?v=gTVeOHiE_n4
I was hoping... by jez9999 · 2011-09-25 00:13 · Score: 2, Interesting

... that it would land on Westboro Baptist Church. Can you imagine old Phelpsy doing a service and them BAM, the whole place is blown to smithereens by a stray solar panel? That would be sign of a just God if there were one...

--
== Jez ==
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Let me get this straight... by linuxwrangler · 2011-09-25 03:11 · Score: 1

NASA has an entire program office dedicated to tracking tens of thousands of pieces of orbital debris as small as 1cm: http://orbitaldebris.jsc.nasa.gov/measure/radar.html
NORAD has a network of satellites and radar stations dedicated to finding incoming threats.
But somehow, despite all this capability and despite tracking the descent of a 5,900 kilogram multi-meter by multi-meter satellite, they don't know where it hit.
?!?

--

~~~~~~~
"You are not remembered for doing what is expected of you." - Atul Chitnis
There's no satellite. I think it's a coverup...... by tunghoy · 2011-09-25 03:27 · Score: 1

I think NASA made up this story to cover a captured Goa'uld cargo ship that was being brought back to Earth.
Drag is a bitch by pavon · 2011-09-25 04:21 · Score: 1

It is a lot easier to track objects moving in a near frictionless environment than to track a object with unstable and constantly changing aerodynamic properties tumbling through the atmosphere.
Re:Tracking systems? by Osgeld · 2011-09-25 04:28 · Score: 1

it wasnt a huge chunk, it was thousands of tiny chunks but thanks for playing
Re:That map by mcswell · 2011-09-25 06:10 · Score: 1

I don't know what map you saw, but an orbit is pretty well defined laterally. The orbit is a great circle (ok, a great ellipse, and not on the ground) with a constant orientation and a known speed; the Earth turns beneath it at a known rate. The orbit is normally well defined vertically also, except when you start hitting air and it slows you down. Hence you can predict exactly (within a few miles) where the satellite will be, so long as it's not *too* much slowed down. And it won't be too slow until the last few hundred miles, when it hits enough air to start burning up.
The lines you saw are the great circles, where the Earth is turning under it. Since each orbits is about 90 minutes (until the last bit of the last orbit), the lines should be a constant distance apart (the distance the Earth rotates in 90 minutes). So yes, they are pretty exact, and the satellite will therefore come down pretty much on one of those lines.
And the rubbish is in your mind.
Debris would be scattered all over the place by spxZA · 2011-09-25 21:07 · Score: 1

I'm trying to figure out exactly who it was, but an amateur astronomer somewhere in South Africa called in to a radio talk show on Saturday indicating that he saw some debris burning up in the early hours of the morning. Trying to get a link up.
The Monge partcipated in the track by boule75 · 2011-09-26 01:34 · Score: 1

The Monge is an big scientific vessel from the French navy, conceived to track ICBM missiles during their re-entry phase and provide precise telemetry for validation purposes. Have a look there (in French) : http://www.meretmarine.com/article.cfm?id=117220

--
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Re:Northwest? Great. by SleazyRidr · 2011-09-26 02:36 · Score: 1

You laugh, but my girlfriend's mother has been talking my ear off about how this satellite doesn't actually exist, and it's just a cover for the comet El Enin, which is going to miss the Earth, but the tail of the comet is going to wipe us out. Apparently it's been in deep space gathering electrons, which will cause massive earthquakes. I tried to explain how earthquakes happen but to no avail. She gave me some holy water and blessed candles with which to protect myself.

--
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Re:Interesting find by Coren22 · 2011-09-27 03:16 · Score: 1

He outed himself by accident, so quit the account. Personally, if I were him, I would have acted like I was parodying Bob, and continued on.

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APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
Re:Interesting find by Coren22 · 2011-09-27 03:21 · Score: 1

Had to reply again, holy shit that site is hilarious

Adelelina Garcia-4 x fitness Olympic Champion
"After sustaining a devastating ACL tear, Dr. Bob helped get me back to competition. I believe the surgery was only 10% of the process and the other 90% I owe to Dr. Bob and his great staff!!!"

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APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?