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Space Science

Satellites Collide In Orbit 456

DrEnter writes "According to this story on Yahoo, two communications satellites collided in orbit, resulting in two large clouds of debris. The new threat from these debris clouds hasn't been fully determined yet. From the article, 'The collision involved an Iridium commercial satellite, which was launched in 1997, and a Russian satellite launched in 1993 and believed to be nonfunctioning. Each satellite weighed well over 1,000 pounds.' This is the fifth spacecraft/satellite collision to occur in space, but the other four were all fairly minor by comparison."
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Satellites Collide In Orbit

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  • by Ethanol-fueled ( 1125189 ) * on Wednesday February 11, 2009 @08:56PM (#26821651) Homepage Journal
    I'm just waiting for one of those things to crash through some suburban American family's house.
    • by Choad Namath ( 907723 ) on Wednesday February 11, 2009 @09:06PM (#26821755)
      Yeah, the thought of that happening is pretty much the only thing keeping me from putting my house in orbit.
    • Re:First collision (Score:5, Insightful)

      by joocemann ( 1273720 ) on Wednesday February 11, 2009 @09:07PM (#26821763)

      That would probably be better than all the debris spreading out and remaining in orbit. That debris, now hundreds of individual pieces, is now able to cause trouble to anything trying to pass through its 'air space', including more satellites, etc.

      Some say that the day we have combat/war in space is the last day we will enter space because the debris will block exit/entry.

      • by Fnord666 ( 889225 ) on Wednesday February 11, 2009 @09:51PM (#26822159) Journal

        Some say that the day we have combat/war in space is the last day we will enter space because the debris will block exit/entry.

        That's why you fire two shots from the ion cannon first to clear a lane!

      • Re:First collision (Score:5, Interesting)

        by jd ( 1658 ) <imipak@ y a hoo.com> on Wednesday February 11, 2009 @10:46PM (#26822613) Homepage Journal

        Some of the early proposals for satellite phones would have put enough in orbit that if any two had collided, the rest would have smashed into the debris field, again resulting in a complete block to launch.

        Remember, one of the early space shuttles was hit by a fleck of paint in orbit. The impact nearly smashed a hole through the windshield. A fragment the size of a dried pea would not necessarily be visible from ground stations on Earth but might easily be expected to punch through any space vehicle in its path, along with anyone inside.

        • Re:First collision (Score:4, Informative)

          by Rakishi ( 759894 ) on Thursday February 12, 2009 @12:51AM (#26823385)

          http://en.wikipedia.org/wiki/Whipple_shield/ [wikipedia.org]

          Small things won't necessarily damage a spacecraft although there's a limit to how much you can protect it and protection does increase the mass.

        • Re:First collision (Score:5, Insightful)

          by Anonymous Coward on Thursday February 12, 2009 @03:57AM (#26824375)

          I was a bit skeptical about this, but I did the math. A large grain of sand (0.03g) would have the same kinetic energy of a 9mm slug at roughly 5.8km/s.

          Orbital velocity at 10K km is 4.93km/s, so it's a reasonable value - and the relative velocity could be doubled if the objects collided head-on.

          Now, I'm sure the shuttle could take shots from a 9mm fine and that much of the energy wouldn't be deposited - it would vaporize the much less massive object, after all. Of course, all of the energy would be concentrated in a very small area and could do a lot of damage...

          Really fascinating. I should be sleeping at 3am, however, rather than calculating orbital impact energies on the back of an envelope...

      • Re: (Score:3, Interesting)

        I vaguely remember a prediction with accompanying animation that at some point, there would be so many satellites that they would start to collide, creating a chain reaction that would damage or destroy many satellites. In the end you would have a sphere of debris that would make the particular orbit uninhabitable for new satellites. I doubt this will be the result from the current collision, but this is still worth thinking about.

      • Re:First collision (Score:5, Insightful)

        by Dan541 ( 1032000 ) on Thursday February 12, 2009 @06:15AM (#26825063) Homepage

        Who would have thought that simply discarding waste would ever become a problem?

    • Re:First collision (Score:5, Insightful)

      by interkin3tic ( 1469267 ) on Wednesday February 11, 2009 @09:12PM (#26821821)

      I know they can FEEL endless when you're in them, but suburbs do not actually take up most of the earth's surface. The chances of that happening are fairly low.

    • Re:First collision (Score:5, Informative)

      by merreborn ( 853723 ) on Wednesday February 11, 2009 @10:19PM (#26822389) Journal

      I'm just waiting for one of those things to crash through some suburban American family's house.

      Rocks the size of these satellites enter earth's atmosphere all the time. Fortunately, we have an atmosphere that does a pretty good job of destroying most smaller objects that enter it. And humans only inhabit a tiny fraction of the earth's surface, so whatever does make it through the atmosphere usually lands in the ocean, or uninhabited areas.

  • by Anonymous Coward on Wednesday February 11, 2009 @08:57PM (#26821661)

    These satellites were Iridium33 (24946) and K-2251 (22675). Now they are pieces of debris from bowling ball sized pieces to vapor.

    A nice little animation of the collision is placed here:

    http://i39.tinypic.com/2vbk75z.gif [tinypic.com]

    This was bound to happen and will happen again. The interesting question is how come they didn't maneuver one of them out of the way. I don't know if 22675 is an active payload that still has power but Iridium33 certainly has the capability of moving. This one was avoidable. Even my non rocket science brain can take the TLEs and figure out that they were passing way too close to each other (I put it at about 500 meters with the latest elements).

    Unfortunately, this didn't create 2 'clouds' of debris. This created one huge field of debris that will continue to expand over time. Many of the pieces will be tracked but the very small pieces cannot be.

    It would have been way cool to observe the collision!

    • by OpenSourceOfAllEvil ( 716426 ) on Wednesday February 11, 2009 @09:02PM (#26821717)
      IIRC from Driver's Ed, the vehicle to the right has the right of way.
    • by erroneus ( 253617 ) on Wednesday February 11, 2009 @09:12PM (#26821823) Homepage

      "Space Chicken!"

    • by MarkRose ( 820682 ) on Wednesday February 11, 2009 @09:16PM (#26821875) Homepage

      The interesting question is how come they didn't maneuver one of them out of the way.

      They couldn't talk to each other because someone took out a communication satellite. Obviously.

    • Re: (Score:3, Informative)

      by geekoid ( 135745 )

      The Russian Sat was not functioning.

    • by camperdave ( 969942 ) on Wednesday February 11, 2009 @09:36PM (#26822039) Journal
      Many of the pieces will be tracked but the very small pieces cannot be.

      As for pieces the size of micrometers, the count will likely be in the thousands.

      These guys [starrett.com] sell micrometers that can measure things as large as five feet across and ones that can only measure up to an inch across. It seems to me that something is the size of a micrometer is somewhat vague.

    • by PhaseChange ( 244013 ) on Wednesday February 11, 2009 @09:53PM (#26822171)

      Hey, you got iridium in my K-2251 (22675)!

      No, you got K-2251 (22675) in my iridium!

      Time for a new tasty treat....

    • by asackett ( 161377 ) on Wednesday February 11, 2009 @10:21PM (#26822401) Homepage

      Actually, any piece large enough to pose a threat to anything we care about can be tracked, and by what counts as ancient technology: the AN/FPS-85 phased array spacetrack radar [globalsecurity.org], for example.

    • by slashtivus ( 1162793 ) on Wednesday February 11, 2009 @10:32PM (#26822489)
      I guess I'll put this in this thread since the others were nothing but attempts at "Funny" mod points:

      Are not the Iridium (and I will assume the Russian satellite as well) very low-orbiting satellites? This would mean the orbits will decay rather rapidly making this really not that big of a deal over the long term?

      Some of the pieces will have gained orbital momentum and go higher, but really most of it should be getting some atmospheric drag and decay quickly.

      • by tweak13 ( 1171627 ) on Wednesday February 11, 2009 @11:08PM (#26822761)
        Yes, these were in what would be considered low earth orbit. How much of a problem this is going to be depends on how many other objects are in nearby orbits that may collide with part of this cloud. The thing about atmospheric drag is that the atmosphere isn't really all that uniform. How a chunk of wrecked satellite with an unknown shape and size is going to react can be predicted, but only to a certain extent. Yes, everything will eventually fall down, even the stuff in a "higher orbit." Those orbits were just made more elliptical, and will eventually come down to about the same altitude the collision happened at. It's going to take awhile though, and those pieces that are too small to track are going to spread over wider and wider areas until they finally reenter. People will be furiously calculating probabilities of collisions for a long time. Decaying 'quickly' is relative I guess, while there is drag to bring them down, pieces will still be up there for years.
        • Re: (Score:3, Insightful)

          One big satellite has relatively little drag-to-weight ratio. Many small pieces have a much larger drag-to-weight ratio because the surface area has greatly increased, but the total mass is still the same.

          therefore, it will come down faster than when there was no crash. In any case, within the foreseeable future.

    • by johannesg ( 664142 ) on Thursday February 12, 2009 @01:41AM (#26823681)

      Even my non rocket science brain can take the TLEs and figure out that they were passing way too close to each other (I put it at about 500 meters with the latest elements).

      I'd put it at about 0.000 meters actually. You can tell from the size of the debris field...

  • by BorgCopyeditor ( 590345 ) on Wednesday February 11, 2009 @08:58PM (#26821683)

    Satellite smoke. Don't breathe this.

  • by AJ Mexico ( 732501 ) on Wednesday February 11, 2009 @08:59PM (#26821689) Homepage
    Too bad orbital tracking didn't give enough warning for Iridium to get their bird out of the way. I guess no one is cross checking the orbits of all satellites? I know it is done for the shuttle and space station. (The space station *has* maneuvered to keep away from space junk.)
  • by fuzzyfuzzyfungus ( 1223518 ) on Wednesday February 11, 2009 @09:07PM (#26821761) Journal
    Hopefully the wreckage from this one doesn't end up causing any unpleasant chain reactions. Not only are satellites really expensive, we currently have no especially good way of ridding ourselves of orbital debris. It would suck to fill our good bits of orbit with trash.
    • by Dripdry ( 1062282 ) on Wednesday February 11, 2009 @09:16PM (#26821879) Journal

      I'm going to play devil's advocate for a second here:

      What if it isn't a bad thing? What if the debris cloud does start some sort of slow chain reaction that knocks out a lot of satellites in orbit and rings earth with debris?

      Although it would be expensive to clean up it would definitely put peoples' minds back on space technology if they suddenly couldn't get tv, phone, internet, gps, or other critical services. It could spur development to clean things up, avoid the problem in the future, and get more nations/people/viable technology in space.

      In our "convenience at any cost" age, perhaps this sort of inconvenience is the kind of thing to slap some sense into us.

      • by fuzzyfuzzyfungus ( 1223518 ) on Wednesday February 11, 2009 @09:28PM (#26821967) Journal
        That seems suspiciously close to "the broken window fallacy" in space. It would cost an enormous amount of money, time, resources, and R&D to clear up a significant orbital debris field. All those resources would(with the exception of any spinoff tech) be squandered, spent just to get us back to where we were before.

        Also, I suspect that such an outcome would be as likely to spur regression as it would expansion. Space is extremely useful, for satellite mapping, GPS, astronomy, and the like; but it isn't necessary. If the costs of exploiting it rise, as they would, drastically, if satellites were constantly knocked out by debris fields; you'd likely see a scaling back of space exploration. Military surveillance and location stuff would probably make the cut; but you could forget about "nonessentials" like orbital telescopes, cheap satellite photography, and the like.
      • Re: (Score:3, Informative)

        by adavies42 ( 746183 )
        ablation cascade [wikipedia.org]
    • Re: (Score:3, Interesting)

      Hopefully the wreckage from this one doesn't end up causing any unpleasant chain reactions. Not only are satellites really expensive, we currently have no especially good way of ridding ourselves of orbital debris.

      There is a scifi story by Ken MacLeod where the orbit around earth is filled with so many satellites that when a war erupts and some of them get destroyed, it starts a chain reaction that ends up shredding all the equipment in orbit and creating a high speed debris belt that prevents space travel for several centuries.

      I've always wondered if that scenario is realistic, but from a physics point of view it sounds like it could be.

  • by NFN_NLN ( 633283 ) on Wednesday February 11, 2009 @09:10PM (#26821797)

    Did Russia have Geico? 15% off public liability insurance for satellites...

  • by funky49 ( 182835 ) on Wednesday February 11, 2009 @09:15PM (#26821863) Homepage
    Was this really bound to happen? I always assumed that when nations put stuff in space, they always included a way to make it de-orbit and burn up in the atmosphere. Littering space is dumb. Can someone please be less politically correct and put some blame on the non-operational Russian sat? Iridium Satellite should file a claim against the Russians. How come a "conjunction analysis" isn't done for all of the objects they're tracking in space? Does there need to be a "Tracking@Home" app for the ps3? In any case, I have a new development idea for the techno-thriller I'm writing... in the future nobody has satellites because of space terrorism. Or maybe I'll start an orbital mechanics company whose job it is to clean up debris and old crap around Earth.

    Funny, I kinda wrote about this in my song "Starblazer [cdbaby.com]"...

    earthlings, knee deep in things
    in orbit there's garbage rings
    • Re: (Score:3, Informative)

      by geekoid ( 135745 )

      One of the Sat.s was a non funtioning sat. When the whole thing fails, you can't really deorbit it..cause it failed.

    • by Cliff Stoll ( 242915 ) on Wednesday February 11, 2009 @09:30PM (#26821997) Homepage

      When a satellite fails, often it cannot be de-orbited. Several failure modes will cause this - the most common is the malfunction of the controller, communications unit, or onboard power system. When any of these fail, there's no way to command the retro-rocket to fire.

      Then, too, you need the satellite to be pointed in the correct direction (meaning that its stationkeeping rockets are working), and for it to have enough hydrazine (or whatever) to be deorbited. Near the end of a spacecraft's life, consumables are limited.

      And, of course, it takes a lot of energy to de-orbit many satellites. A geostationary comsat needs one heck of a kick motor to get it down. Usually they are not brought down to burnup in the atmosphere. Instead, they are moved a few dozen (hundred?) kilometers inwards from their geostationary slot. This puts 'em well away from the main circle of geostationary satellites.

      It's like consumer goods ... manufacturers work to make them last long enough to complete their mission; few think about how to get rid of 'em once their purpose has expired.

      • by Anonymous Coward on Wednesday February 11, 2009 @10:08PM (#26822279)

        Informative post but just one correction, at end of life the birds in geo RAISE their orbit. Decay takes so long that the graveyard orbits are stable over pretty much everyone's planning horizon (centuries+). If collisions occur up there then relative velocities are hopefully small enough to limit the debris field.

    • by Zak3056 ( 69287 ) on Wednesday February 11, 2009 @09:37PM (#26822057) Journal

      Iridium Satellite should file a claim against the Russians.

      Typically, when it comes to right of way, the less maneuverable vehicle has the right of way (for example, a balloon has the right of way over a glider, which has the right of way over an airship, which has the right of way over an airplane. Similar rules apply to seaborne vessels.) Taking at face value the summary's statement that the Russian satellite was non-functional, it was clearly the duty of the operators of the Iridium satellite to take action. If you want to talk claims/liability, I'd say that the Iridium folks are on the hook for huge damages--through negligence they've created a massive hazard to navigation that will be a problem for... what, centuries?

  • a Russian satellite launched in 1993 and believed to be nonfunctioning.

    It's a cover-up, Soviet nukes are falling from space, run for your lives!

    • by denzacar ( 181829 ) on Wednesday February 11, 2009 @09:25PM (#26821947) Journal

      James Bond has safely crashed that Iridium satellite into the Russian cold war doomsday device satellite somewhere over Siberia.

      After that, he has as usual returned to having sex with female scientists that look like supermodels.
      All is well with the world once more.

  • A good question.... (Score:4, Interesting)

    by reality-bytes ( 119275 ) on Wednesday February 11, 2009 @09:16PM (#26821877) Homepage
    TFA says that they knew this would happen 'sooner or later' but doesn't mention anything specific.

    The question is, did anyone have any specific knowledge of the likelihood of this specific collision prior to the event?

    I'm assuming just now there wasn't orbital information of sufficient precision to predict this.
  • by Baldrson ( 78598 ) * on Wednesday February 11, 2009 @09:23PM (#26821929) Homepage Journal
    This is a good example of why circular, indeed any high-perigee orbit should be reserved for applications like tether propulsion [wikipedia.org] such as HASTOL Rotovators [wikipedia.org].

    Low perigee orbits, orbits that dip into upper atmosphere, naturally decay to reentry. If collisions occur, the pieces will naturally decay to reentry.

    Rotovators are highly valuable and actually need to operate in LEO to throw things out of LEO, both up and down -- and Rotovators are quite vulnerable to debris.

    500 mile perigee is way to high. It is a nighmare orbit for debris proliferation.

    • by Dun Malg ( 230075 ) on Wednesday February 11, 2009 @10:14PM (#26822333) Homepage

      Rotovators are highly valuable and actually need to operate in LEO to throw things out of LEO, both up and down -- and Rotovators are quite vulnerable to debris.

      Blah, blah, blah. Rotovators [wikipedia.org] are "valuable" the same way unicorns and genies are "valuable", which is to say they are valuable in theory, but since we don't have any nor do we have any prospect of acquiring any anytime soon, it would be completely ridiculous to make expensive financial concessions based on this imaginary "value".

      • by Baldrson ( 78598 ) * on Wednesday February 11, 2009 @10:32PM (#26822493) Homepage Journal
        The risk adjusted net present value of unicorns is basically 0 because the risk of their not existing is close to 1. Of genies, well that depends on your religion, but for the vast majority of folks making economic decisions with real money, its 0. Of "Rotovators" of the type linked to by you, it is probably higher than space elevators but lower than the HASTOL rotovator type I linked to by quite a lot because the HASTOL rotovator can be constructed with current materials and suborbital launch vehicles now going into commercial operation.

        So a fair comparison has to compare the economies of a HASTOL rotovator, adjusted for the technological risk, to the difference between current high perigee LEO applications and modification of those applications to have perigees low enough to naturally reenter at about the same time the satellite is at the end of its projected useful life.

        The trade-off is not nearly as clear as you make it out to be, and with the value of getting things to and from space being essentially "halfway to anywhere", it is pretty clear that you've got a lot weaker case than you apparently think.

  • 5th collision?? (Score:5, Informative)

    by Anonymous Coward on Wednesday February 11, 2009 @09:29PM (#26821985)

    I know of 3 previous collisions.

    1991-12-23 COSMOS vs. COSMOS DEB (discovered in 2005)
    1996-07-24 CERISE vs. Ariane R/B
    2005-01-17 Thor Burner vs. CZ-4 DEB

    What's the 4th previous??

  • Planetes (Score:5, Interesting)

    by Bonker ( 243350 ) on Wednesday February 11, 2009 @09:32PM (#26822005)

    Planetes is a japenese cartoon about this very subject [wikipedia.org], and other unpleasant realities of space travel including space-radiation induced cancer, the birth problems of people living on the moon, and the long delay involved in inter-planetary travel.

    The main character, 'Hachimaki', is basically a space garbage collector.

    • Re:Planetes (Score:5, Informative)

      by Logic and Reason ( 952833 ) on Wednesday February 11, 2009 @10:43PM (#26822571)
      A garbage-collecting ship like the Toy Box is not likely to be feasible for anything other than the largest debris pieces. You would have to expend huge amounts of energy to match velocities with each little group of debris, and you wouldn't get much useful scrap from them. The wiki page you mention actually discusses this briefly.
  • by john_anderson_ii ( 786633 ) on Wednesday February 11, 2009 @09:43PM (#26822097)
    It's time for MegaMaid. Get NASA started on that Spaceball-1 project STAT.
  • by capebretonsux ( 758684 ) on Wednesday February 11, 2009 @10:06PM (#26822267)
    if it collided with a $100,000 toolbag....
  • by computersareevil ( 244846 ) on Wednesday February 11, 2009 @10:20PM (#26822395)

    This is one way the theoretical Ablation Cascade [wikipedia.org] could start. At least then we wouldn't have to worry about getting to the Moon. We couldn't.

    Bummer if it happens before the Webb Space Telescope launches...

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