Defunct Satellite To Fall From the Sky

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Defunct Satellite To Fall From the Sky

Posted by Soulskill on Friday September 9, 2011 @07:23AM from the try-not-to-get-hit dept.

Front page first-timer EmLomBeeNo sends word of a 6.5-ton satellite that will soon be making a quick and fiery return to Earth. From Space.com: "The huge Upper Atmosphere Research Satellite (UARS) is expected to re-enter Earth's atmosphere in an uncontrolled fall in late September or early October. Much of the spacecraft is expected to burn up during re-entry, but some pieces are expected to make it intact to the ground, NASA officials said. The U.S. space agency will be taking measures to inform the public about the pieces of the spacecraft that are expected to survive re-entry." According to a NASA press conference today, you have a 1-in-21 trillion chance of being hit by falling debris. Who's feeling lucky?

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Methinks the public doesn't appreciate odds by elrous0 · 2011-09-09 07:24 · Score: 2, Insightful

Every day idiots all over the U.S. throw down $1 for a 1 in 100 million chance of winning some big jackpot lottery. So, on the off chance that said idiots stumble upon a news channel while channel-surfing between "The Jersey Shore" and Maury Povich's "Primetime Baby-Daddy Special" (and assuming that they're not too high to understand what's being said), there is a pretty good chance that they'll completely ignore the "1-in-21 trillion chance" addendum and only hear the "being hit by falling debris" part. In this case, I would say the odds of them panicking, and then going out and spending the last bit of their McDonalds paychecks on booze and "Huffers Own"-brand industrial glue are pretty goddamn high.

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SJW: Someone who has run out of real oppression, and has to fake it.
1. Re:Methinks the public doesn't appreciate odds by elrous0 · 2011-09-09 08:05 · Score: 3, Funny
  
  I heard some girl got killed by a toilet seat from Mir when they deorbited it. But that could just be a rumor.
  
  --
  SJW: Someone who has run out of real oppression, and has to fake it.
2. Re:Methinks the public doesn't appreciate odds by sconeu · 2011-09-09 08:22 · Score: 2
  
  I heard she later became a Grim Reaper.
  
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  General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
3. Re:Methinks the public doesn't appreciate odds by Skater · 2011-09-09 08:23 · Score: 2
  
  There was an article in the Washington Post this morning about people who are afraid to go to public events for fear of terrorist attack. I'm sure many of those very same people don't think twice about getting in a car.
4. Re:Methinks the public doesn't appreciate odds by Teckla · 2011-09-09 08:54 · Score: 2
  
  I wonder which is worse: spending $1 in exchange for a little enjoyable fantasizing about what it would be like to be rich, or complaining endlessly on Slashdot about how stupid everyone else is.
Terrible word choice by zill · 2011-09-09 07:26 · Score: 2, Insightful

uncontrolled fall
There's a reason why engineers shouldn't write press releases.
1. Re:Terrible word choice by jeffmeden · 2011-09-09 07:33 · Score: 4, Funny
  
  What, you would rather an engineer AND a communications major be required to produce the press release, in order for it to change from "uncontrolled fall" to either "planned gravitationally-assisted descent process" (if you were told to spin it "for") and "massive, fiery man-made meteor raining death on unsuspecting victims" (if you were told to spin it "against")?
2. Re:Terrible word choice by frosty_tsm · 2011-09-09 08:13 · Score: 2
  
  What, you would rather an engineer AND a communications major be required to produce the press release, in order for it to change from "uncontrolled fall" to either "planned gravitationally-assisted descent process" (if you were told to spin it "for") and "massive, fiery man-made meteor raining death on unsuspecting victims" (if you were told to spin it "against")?
  You could just call those the "CNN" and "FOX" versions.
Yeah, so I don't understand the decision here by JoshuaZ · 2011-09-09 07:32 · Score: 4, Informative

So apparently they used the remaining fuel a few years ago to move it into a more rapidly decaying orbit. If they had enough fuel to do that why not just deorbit the whole thing in a controlled fashion and aim it at an ocean? We've done that before. Obviously these are some very smart people but it seems weird that they'd have exactly enough fuel to put it into a rapidly decaying orbit but not enough fuel to handle that last little bit.
On the bright side, the danger from deorbiting satellites is pretty small. The biggest actual problem that has occurred when a Soviet satellite with radioactive material decided to scatter itself over a large part of Canada back in the 1970s http://en.wikipedia.org/wiki/Kosmos_954. When the US space station Skylab pulled a similar stunt over Australia, the local government fined NASA a few hundred dollars for littering.
1. Re:Yeah, so I don't understand the decision here by clarkn0va · 2011-09-09 07:46 · Score: 2
  
  why not just deorbit the whole thing in a controlled fashion and aim it at an ocean?
  Or a Michael Bolton concert, assuming you're trying to minimise the chance of it hitting someone.
  
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  I am literally 3000 tokens away from the chaotic crossbow --Stephen
2. Re:Yeah, so I don't understand the decision here by Rich0 · 2011-09-09 08:45 · Score: 2
  
  Well, the fact that it took years to de-orbit even after lowering the orbit suggests that they just ran out of fuel.
  De-orbiting a satellite takes quite a bit of fuel, actually. I doubt that most carry that much. They are trying to carry enough to get the satellite into a low enough orbit that it eventually de-orbits, so that they aren't stuck up there forever. Things like geosync satellites don't have nearly enough fuel to do even that - you'd need something resembling the booster rocket that put it in orbit to get it back down, and it might almost be as energy efficient to just send it to the moon or something.
3. Re:Yeah, so I don't understand the decision here by doublebackslash · 2011-09-09 10:24 · Score: 2
  
  Think of it this way, all orbital changes take energy. Now that is obvious but bear in mind that ALL orbital changes take energy. What I'm getting at is that the velocity for a satellite determines its altitude range (or just it's altitude in the case of a circular orbit).
  Since any change in velocity takes energy (fuel) and the difference between an orbit that is 100% clear of the atmosphere is a vastly different energy than one that is mostly or all in it. Now, on the other hand if you intentionally make the orbit highly elliptical you can have the satellite skim the outer atmosphere at closest approach. Sounds like they BARELY got there and the thing to keep in mind about the upper atmosphere is that it is not a solid line "atmosphere starts here" and even at a given altitude the density varies wildly.
  Seems like they got it into as elliptical an orbit as they could and then had to rely on atmospheric breaking in an atmosphere that might be described as a "soft vacuum" in a laboratory. With those sorts of time scales and depending on the atmosphere it is little wonder that the target and timeframe were what they were. "Earth" and "sometime in the next X years".
  As it get closer to re-rentry they will be able to make much better predictions but the last few orbits will eat the majority of the speed (exponential decay) so there isn't much to do till then but keep watching and waiting.
  
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Re:Chance by Ruke · 2011-09-09 07:42 · Score: 2, Informative

Yep. TFA puts the odds at about 1:3200, actually.
Measures to inform the public by sl4shd0rk · 2011-09-09 07:51 · Score: 4, Funny

NASA says run, but not in a straight line.

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Toilet Seat Girl by sacridias · 2011-09-09 07:55 · Score: 3, Interesting

Not sure how many are fans of dead like me, but the simple fact that she got nailed by a toilet seat comes to mind with this story.
Just be careful not to get hit, as you will be nicknamed toilet seat girl/boy for the remainder of your unlife.
Re:Chance by Archwyrm · 2011-09-09 08:09 · Score: 2

Well is there anything we can do? Like lie down and put a paper bag over our head or something?

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Fascism should more properly be called corporatism because it is the merger of state and corporate power. -- Mussolini
Re:Odds? by jandrese · 2011-09-09 08:34 · Score: 3, Informative

The actual odds for shuttle failure on each launch were calculated to be about 1 in 100, which ended up being pretty close to reality.

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Re:Chance by WrecklessSandwich · 2011-09-09 08:57 · Score: 2

Even worse! The Chinese satellite that got blasted a few years back is now 2317 traceable pieces. If the odds are for 1 piece, then odds are about 75% somebody is going to get thwacked!
Or maybe not.
Very much maybe not. That figure makes the assumption that none of the pieces will burn up on re-entry. Given that it's already in small pieces that will individually burn up more easily and that UARS is "huge" (I have no info on the Chinese ex-satellite, but let's assume for the moment that it was of fairly average size), the chances of being hit by a piece of that Chinese satellite are probably far lower.
Re:i love by Dr+La · 2011-09-09 09:45 · Score: 2

Actually, many/most countries are signatory to the Space Treaty that specifically states (amongst other things) that any space debris landing on their territory has to be turned over to the country who launched it, if the latter wishes so. So yes: by international law, UARS remains US property.

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Re:Odds? by 0123456 · 2011-09-09 10:29 · Score: 2

The actual odds for shuttle failure on each launch were calculated to be about 1 in 100
Only after it blew up the first time. Before that the 100,000 number was often quoted; ISTR Feynman referencing it during the Challenger investigation.