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Space

ISS Dodges Space Junk For First Time In Five Years 141

Posted by kdawson
from the missed-me-nyah-nyah dept.
Kligat writes "For the first time since 2003, the International Space Station has utilized the rockets on the European Space Agency's Automated Transfer Vehicle to dodge leftover remnants of a defunct satellite. The Russian Cosmos-2421 was launched in June 2006 to track Western Navy vessels and is believed by NASA to have exploded — 'likely due to a self-destruct command issued by Russian officials' according to the article — leaving 500 pieces of space debris. Ordinarily, the rockets on the ATV are used to take the ISS away from Earth's atmosphere and reduce drag. In this case, the 5-minute firing caused the ISS to move downward because it was already near the top of its acceptable range. Estimated probability of impact was 1 in 72, and an avoidance maneuver is called for if the probability is greater than 1 in 10,000. The space junk was predicted to pass the ISS within just a mile."
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ISS Dodges Space Junk For First Time In Five Years

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  • by LostCluster (625375) * on Monday September 01, 2008 @05:52PM (#24835719)

    You watch out for spy satellites!

    • lol

    • Actually, this really sucks because the rockets were used to LOWER the ISS. What a waste. I wonder how much warning they get before estimated impact.

      • Re: (Score:2, Insightful)

        by aonic (878715)

        while it seems like a waste cause the rocket fuel was used to cancel out a previous boost maneuver, keep in mind that the ISS needs to be within a certain altitude band to be reachable by the soyuz/shuttle. also, the humans on board necessitate resupply missions more often than boost manuevers are required anyway.

      • by ctetc007 (875050) on Monday September 01, 2008 @08:19PM (#24836907) Homepage

        Actually, this really sucks because the rockets were used to LOWER the ISS. What a waste. I wonder how much warning they get before estimated impact.

        Actually, they were planning to lower the ISS for the next few missions anyway so that the shuttle would be able to bring up more cargo than usual. This maneuver wasn't so much a waste as it would seem to be.

      • Actually, this really sucks because the rockets were used to LOWER the ISS. What a waste. I wonder how much warning they get before estimated impact.

        It's not like ISS is trying to get to Mars. It's a space station, it just goes around in circles.

        • Yup it's a space station, not some silly moon (even if it acts like it) ;)

        • The ISS is slowed by atmospheric drag, so it must be reboosted every so often. This maneuver cancels out a reboost effort, so that reboost effort, and this manwuver, were just a waste of fuel.

    • Someone call debris section!
  • Pure case of state-controled media going on in Russia. They're not willing to admit they had a spy satellite in the first place, so they're not able to explain where the debris came from. That turns out to be something NASA is more than willing to do for the American side.

    • by Kligat (1244968) on Monday September 01, 2008 @05:59PM (#24835791)
      Russian news avoids [en.rian.ru] mentioning the Russian satellite and just refers to the ISS dodging a "cluster of garbage."
      • by neonsignal (890658) on Monday September 01, 2008 @09:04PM (#24837283)
        maybe they were just quoting the engineers who had built the satellite...
    • by icegreentea (974342) on Monday September 01, 2008 @06:02PM (#24835823)
      NASA doesn't have any spy satellites. The Defense Department does. I wouldn't be surprised if there are a few fields of debris from US spy satellites that haven't been announced or anything. Such information is somewhat sensitive, and official denial may be important. Could be anything from 'protect the existence the other spy satellites in its family' to 'let's save face'. To be fair, I could totally see your DoD doing something similar.
      • Re: (Score:3, Funny)

        by Anonymous Coward

        NASA doesn't have any spy satellites.

        I just mentioned that to my Martian friend, and he said "Gzornak frokka wa Hubble, flrckin earthling!"

        • by Tetsujin (103070)

          NASA doesn't have any spy satellites.

          I just mentioned that to my Martian friend, and he said "Gzornak frokka wa Hubble, flrckin earthling!"

          Meh, give the Martian some water, and he'll grok that he is your bitch.

      • by digitalchinky (650880) <dtchky@gmail.com> on Monday September 01, 2008 @11:34PM (#24838445)

        The problem with this theory is that there are about 100,000 geeks in the world that love nothing more than to tag every single man made object in space. They even have programs to show every bit in real time graphically orbiting the planet. Many of these are free for download.

        You can't put or have anything in space bigger than a small stone and not have some government or organization find and tag it, only to release that data to the general public at some point not very long after that. Lots of RADAR being pumped out in to space just for this very purpose.

        If the ISS was moving because of anything other than debris from a Russian spy sat, then the slashdot headline here would spell it out. Even the military make use of the work from these guys, it can sometimes actually be more up to date.

        Me: Ex 3 letter agency drone that worked in the satellite area for a while.

    • Re: (Score:2, Informative)

      by Dr La (1342733)

      "That turns out to be something NASA is more than willing to do for the American side."

      You wish. There are over 140 US objects tracked by us amateur satellite trackers which are classified - i.e. they officially do not exist and the only public data on their orbits comes from us amateur trackers. Not NASA, the DoD or any other US government agency.

  • A mile? (Score:4, Interesting)

    by XanC (644172) on Monday September 01, 2008 @05:58PM (#24835773)

    Aren't orbital trajectories pretty well known? How is there a 1 in 72 chance that the thing will make a sudden mile-long jog and hit the station?

    • by Jugalator (259273)

      Hmm, good question. I suppose only SchrÃdinger's Cat knows for sure. :-/

      • Re: (Score:1, Funny)

        by Anonymous Coward

        Haven't you done enough to that poor cat.

        Cats are people too.. only with paws and fur and they taste good in chinese food.

      • Re: (Score:3, Informative)

        by mbone (558574)

        According to that list [nasa.gov], there are 12 objects with a probability >1/10,000, and 2 with a probability > 1/1000.

        Note that the uncertainty on these orbits is frequently many 1000's of km; the orbits of things in LEO are much better determined.

    • Re:A mile? (Score:5, Insightful)

      by ArchieBunker (132337) on Monday September 01, 2008 @06:41PM (#24836091) Homepage

      Because when dealing with the vastness of space a mile is pretty damn close.

    • Re:A mile? (Score:5, Informative)

      by Colonel Korn (1258968) on Monday September 01, 2008 @06:47PM (#24836151)

      The orbital trajectory of every piece of debris from a spy satellite that was intentionally blown up isn't so well known, especially when the nation controlling the satellite wants it to be a secret.

      • Re: (Score:1, Offtopic)

        by CodeBuster (516420)
        That is why we have radar. It seems like it would not be too difficult to install a radar (if one is not installed already) and have an onboard computer continually track objects, calculate orbital trajectories, and alert the crew and ground control if any piece of junk large enough to be tracked (above a configurable threshold) will intercept the imaginary sphere which contains the ISS.
        • Re:A mile? (Score:5, Insightful)

          by c6gunner (950153) on Monday September 01, 2008 @08:52PM (#24837197)

          While that's a valid point for some situations, radar systems tend to have problems tracking objects below a certain size. A marble moving at 36,000 miles an hour isn't likely to be picked up by any radar array that I've ever seen.

          The other problem is that they suck up a lot of juice. An active radar dish blaring away 24/7 would be a significant drain on the electrical power available to the ISS. I can't say it's not possible since I don't know how much their solar arrays can generate, but I'm willing to wager that it'd be a problem.

          • by cmacb (547347)

            Add to what you said that if the debris is traveling at a high speed WRT the ISS, even if it could be detected by radar there wouldn't be a whole lot of time to do anything about it.

        • by RockDoctor (15477)

          It seems like it would not be too difficult to install a radar (if one is not installed already) and have an onboard computer continually track objects, calculate orbital trajectories, and alert the crew and ground control if any piece of junk large enough to be tracked (above a configurable threshold) will intercept the imaginary sphere which contains the ISS.

          Leaving aside the resolution and power consumptions issues that other respondents discuss, look at the ranges involved. According to Wikipedia, the I

        • The trouble with that is that say you need an hour to plan and exectute an avoidence manoeuvre (and I bet in practice it takes much longer).

          Lets assume that the junk is in a similar orbit to the ISS but going in the opposite direction. That would place the junk over 30 thousand miles away at planning time. That is a long way away and going to be extremely difficult to detect. It may even be too far away to see at all due to the earth obscuring the view (remember the ISS is only a couple of hundred miles hig

    • The satellite is exploded, maybe they don't know how far out the little pieces go.
    • Re:A mile? (Score:5, Informative)

      by DirtySouthAfrican (984664) on Monday September 01, 2008 @07:04PM (#24836303) Homepage

      At the risk of being redundant, it's roughly a 1 in 72 chance that their calculations of a "miss" are off. Calculations of this sort involve a margin of error, from not precisely knowing locations of these objects to not being able to do forecasting accurately enough. Debris A gets hit by debris B (which somehow evaded your radar), sending off two new chunks of metal which weren't even IN your original calculations. I'm actually impressed that they can put solid numbers on these things, but I guess that's what supercomputers are for.

      Yay for safety margins.

    • by aug24 (38229)

      The trajectories are actually chaotic, although roughly linear (well, elliptic) around the earth. As the bits also orbit around the moon, the ISS itself, and each other, there is no possible way to accurately predict their location in the future - the error margins will grow with time until a new and precise observation is made.

      Q.V. The three-body problem [wikipedia.org], and, more generally, the n-body problem (same page).

      Justin.

    • orbital trajectories pretty well known, yes but hard to predict out to the future. So while you might know exactly where something is right now what you don't know is where exactly is will be next week. The unknowns are things like how much drag might slow it down, the atmosphere is not 100% constant and we don't know the shape of the object. Earth's gravity varies be location. We don't know about Solar activity and then there is the gravitational effects of the sun, moon and planets (Jupiter). With so

    • by Cecil (37810)

      Only to a certain degree of accuracy. There is no such thing as perfect accuracy to begin with, then there are a lot of unknown variables. While it's been up there orbiting, has it been hitting things that are too small for us to detect and pushing it off course? Has it changed it's orientation slightly and now has a minutely different amount of drag from air particles? Were our measurments off to begin with? We don't know, and these things can add up to huge amounts over time.

      A 71 in 72 chance of being les

  • space station dodge you
  • by spotter (5662) on Monday September 01, 2008 @06:32PM (#24836027)

    this post made me wonder. could they repurpose the nautilus anti missle laser system to knock the space junk that threatens the station out of the vacum of space. Or could it make things worse? (lots of tiny particles you can't avoid vs. a couple of big particles.

    • Cooling might be a problem. If your laser is powerful enough to vaporize a couple tons of debris, and transfer enough kinetic energy to change their orbit so they no longer intersect, its going to generate a good deal of heat. Maybe the ISS's current radiator can't handle it. Firing rockets is easier cause you get to dump all a lot of waste heat into your reaction mass and throw it into the void.
    • by dominious (1077089) on Monday September 01, 2008 @07:30PM (#24836507)

      Or could it make things worse? (lots of tiny particles you can't avoid vs. a couple of big particles.

      well, what we need then is a linux admin who has mastered that Asteroids game

    • But how would you get the sharks into orbit?
  • Time to call the Space Debris Section of Technora Corporation.... I wonder how far something like Planetes is off from reality at times. Excellent series. GrpA
  • Planetes (Score:1, Informative)

    by Anonymous Coward

    Any fans of the anime Planetes [wikipedia.org] ?

    • by j1m+5n0w (749199)
      I was actually thinking about ordering it just yesterday. I haven't seen it, but it seemed to get good reviews on Amazon, and sounded like the science was pretty sound.
      • Re: (Score:3, Informative)

        by Narishma (822073)
        It's very good. And it's the only anime I've seen where there's no sound in space.
  • Recycle It! (Score:4, Funny)

    by Hoffer53 (832181) on Monday September 01, 2008 @08:30PM (#24837023)

    They should attach large electromagnets to the ISS and collect all of the space junk it passes by for recycling. I wonder what payment the recycling depot would give for satellite parts.
    I don't keep track of shuttle payloads, but I would imagine that there would be room for a satellite or two in the cargo bay on the return trip.

    • All kidding aside, the value of a pound of aluminum in LEO has to be thousands of dollars... I wonder if someday it might make sense for a larger, commercial space station to try to capture any random piece of matter that crosses its orbit, just for raw materials.
      • But what are you going to do with a pound of aluminium in LEO? You could use it as a doorstop maybe, but I'm not so sure that building a smithy in space is going to be cost effective. The anvils alone will cost a fortune to send up there!
    • Yeah, I imagine some of the top-secret nuclear waste some of them might be recovering is totally worth a lot of money!!!

    • Name it the inconvenient Al Gore enviro-shuttle...

      Is there a such thing as polluting the universe?

    • There are two problems.

      The first is relative speed, it is extremely difficult to collect something that is moving at thousands of miles per hour relative to you. Shuttle missions to visit/retrive something existing (e.g. the ISS or the hubble) have to be carefully planned so they match orbits.

      The second is even if you found a way to retrive them they aren't going to be all that valuable. Afaict most of the cost of a sattalite is in the cost of the precision engineering and the cost of the launch not the cos

  • Within 1 mile? (Score:4, Informative)

    by p3d0 (42270) on Monday September 01, 2008 @08:34PM (#24837047)

    That's a heck of a close call, considering the ISS is traveling at 4.8 miles per second. That's little like a car at highway speed running a red light and missing another car by less than one car length.

    • Re:Within 1 mile? (Score:4, Interesting)

      by c6gunner (950153) on Monday September 01, 2008 @08:58PM (#24837249)

      That's a heck of a close call, considering the ISS is traveling at 4.8 miles per second. That's little like a car at highway speed running a red light and missing another car by less than one car length.

      Not really, since their relative speeds may be far less. If the debris cloud is traveling on the same trajectory at 4.7 miles per second, then their relative velocity is only 360 miles per hour.

      On the other hand, if it's traveling on the exact opposite trajectory at the same speed .... ouch.

  • ISS altitude graph (Score:5, Informative)

    by j1m+5n0w (749199) on Monday September 01, 2008 @08:53PM (#24837199) Homepage Journal
    Here's a graph of ISS altitude [heavens-above.com] for the last year, if anyone is interested in hard data. (The steady downward slope is due to atmospheric drag, and the sharp increases are from firing maneuvering thrusters to maintain altitude. Presumably, the recent abrupt drop was the maneuver described in the article.)
  • Anyone here know how they calculate "impact probability" ? I mean, my poor man's logic seems to think you either hit something, or you don't. Bool 1, or Bool 0.

    If you miss something by a mile, how does that wind up being a 1 in 72 probability ? No offense to the space buffs, of which I am not one, but that sounds like game show odds to me: "You're bound to lose, but let's all act excited anyway!"

    • Re: (Score:3, Informative)

      by cyclone96 (129449)

      The calculated miss distance was about a mile, but there was uncertainty in that miss distance such that there was a 1 in 72 chance it wouldn't miss the ISS, but instead hit it directly.

      To answer your question (at a high level), the sensors and models that are used to track and predict the debris locations have associated mathematical models that can put a number on the uncertainty of where that debris is. The uncertainty takes into account things like how many radar obs were made, the inherent accuracy of

  • by BinBoy (164798) on Monday September 01, 2008 @10:14PM (#24837849) Homepage

    > ISS Dodges Space Junk For First Time In Five Years

    It must be really banged up after 5 years of hitting space junk.

    Admit it! You thought it too!

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