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Space

3.5 Ton Satellite to Crash Back to Earth 323

Posted by chrisd
from the guess-my-pellet-gun-was-more-powerfull-than-I-thought dept.
DeadBugs writes "CNN is reporting that the NASA Extreme Ultraviolet Explorer could crash back to earth in a matter of days. It's estimated that up to 9 large pieces (4-100 lbs.) of the Satellite could survive re-entry. Unlike the Compton Gamma Ray Observatory that was guided in, this Satellite will be uncontrolled. The EUVE has only been up there since 1992.... I wonder when this sort of thing will start to be a more common event."
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3.5 Ton Satellite to Crash Back to Earth

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  • first post (Score:3, Interesting)

    by keshto (553762) on Tuesday January 29, 2002 @11:58PM (#2923241)
    I wonder if they can predict what the "catchment area" of the debris is going to be.. -keshto
    • Re:first post (Score:3, Informative)

      by digitalunity (19107)
      Not yet. It is falling without thrusters or any way to move itself. Only time will tell it's exact trajectory.

      The article did mention that the trail from this thing could stretch up to 625 miles. They also said that the parts that won't burn up are made out of titanium and steel. Seeing as Titanium is really expensive, if all of it hit me in the head; at least I could sell it to pay for the medical bills!
      • by nomadic (141991)
        If you get hit in the head by a piece of titanium travelling approximately 1300 feet per second, you probably won't have to worry about medical bills, or much of anything else for that matter.
        • I'm excited. How about you?
          Maybe it'll hit my car. Hang on, I gotta go buy some insurance from Lloyds real quick :)
          • Maybe it'll hit my car. Hang on, I gotta go buy some insurance from Lloyds real quick :)

            Don't bother, if your car were to be hit by a piece of space junk its value as a "collectable" would be far greater than its insurance valuation.
        • Re:first post (Score:2, Informative)

          by PhuCknuT (1703)
          It won't be travelling nearly that fast when it hits the ground. Terminal velocity is much lower. There is at least 1 case of someone being hit by a meteor and surviving with only a bruise.
        • If you get hit in the head by a piece of titanium travelling approximately 1300 feet per second, you probably won't have to worry about medical bills, or much of anything else for that matter.

          If you get hit by something travelling at that speed, it dosn't matter what element it is made of. But unless it is either very large or aerodynamically shaped there is no way you are going to get anything from space travelling at anything like that kind of speed from space. Anything dropped into Earth's atmosphere is subject to a "terminal velocity", where drag from the air equates to 1G. Since the Earth's atmosphere is of varying density the force due to drag can quite easily excede 1G.
          • Well, not sure why everyone seems to assume I just made up that figure, but I'm curious to see what other people's calculations would be. I assumed a 1 inch sphere of titanium, though admittedly I fudged the air density and viscosity (well, I made sure they fell within the range of possible values for air at 0 atmospheres), but I wasn't going to kill myself over a comment on slashdot. If someone has a more accurate value, by all means post it.
      • by The Original Bobski (52567) on Wednesday January 30, 2002 @12:37AM (#2923469) Homepage Journal
        Not yet. It is falling without thrusters or any way to move itself. Only time will tell it's exact trajectory.

        Oh, great. Time to dust off the old SkyLab Detector hat.
      • Titanium is under $3.50/pound (about 5 times the price of aluminum, for comparison). You'd have to get hit with a hell of a lot of it to pay any decent medical bill.
      • They have all the numbers, they can probably calculate where the debri will spread within 10%, easy.
    • by Y B MCSE (469234) on Wednesday January 30, 2002 @12:24AM (#2923387) Homepage
      I wonder if they can predict what the "catchment area" of the debris is going to be..

      Not to worry...Taco Bells top scientists are working on it at this moment.
  • by Have Blue (616) on Tuesday January 29, 2002 @11:59PM (#2923245) Homepage
    Did NASA think they had to get hip to the 90's X-games obsession or something? Take ultraviolet measurements WHILE SNOWBOARDING!
  • by AltGrendel (175092) <ag-slashdot&exit0,us> on Tuesday January 29, 2002 @11:59PM (#2923249) Homepage
    ...that some joker will have a piece of it up for auction on e-bay before the derbis has cooled.
  • This is likely to become far more common. More and more old satellites are being shut down, and people tend to spend their satellite funding on running and using the satellite, not bringing it down safely. Maybe i should start selling insurance....
    • Insurance? Well, you would have to find some really dumb people considering the odds.

      Perhaps the man who robbed a store with a tree branch [slashdot.org] might be interested.
      • by Cruciform (42896) on Wednesday January 30, 2002 @01:20AM (#2923616) Homepage
        Or one of these [space.com] people?

        In November 1954 a housewife in Alabama was struck by a 3-lb (1.4 kg) meteor that smashed through her roof, bounced off some furniture, and struck her in the hip as she lay sleeping. She received a large bruise but no other harm.

        In October 1992 a 26-lb (12 kg) meteor punched clear through the trunk of an automobile in Peekskill, New York, wrecking the aged Chevrolet (but also turning it into an instant collector's item that sold for over $20,000).

        In June 1994 a man driving near Madrid, Spain suffered a broken finger when a 3-lb (1.4 kg) meteor crashed through his car's windshield and smashed the steering wheel, ending up in the back seat.


        or here [branchmeteorites.com].

        Unfortunately I couldn't find the link to the central park jogger that got nailed a few years ago. Although all it did was bounce off him. It made many major newspapers though. Anyone got a reference?
    • by interiot (50685) on Wednesday January 30, 2002 @12:34AM (#2923452) Homepage
      The article mentions that this satellite was designed to be decommisioned this way-- no steering mechanism was included. Is this a common occurance? Can't the designers be held liable if damage occurs?
      • by BlowCat (216402) on Wednesday January 30, 2002 @02:48AM (#2923860)
        This satellite is provided by its designers "as is" and any expressed or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed.

        In no event shall the designers of the satellite be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption; destruction of cities, countries, continents; death of all humans) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this satellite, even if advised of the possibility of such damage.

        • Reminds me of the small print of an insurance contract I got some years ago that said they wouldn't help me in case of nuclear war.

          Pffff, I hate dandy insurance restrictions.

          /max
      • My homeowner's insurance (not sure why they call it that since I'm a renter) policy includes coverage for the following:

        5. Aircraft, including self-propelled missiles and spacecraft.

        Who knows, maybe my insurance company would go after the spacecraft designers/operators/whoever -- or, more likely, after their insurance agency.

    • by John Harrison (223649) <johnharrison.gmail@com> on Wednesday January 30, 2002 @12:37AM (#2923475) Homepage Journal
      Any satellites put into orbit should be required to have the capability of being brought down safely. Maybe this doesn't need to become a requirement for all satellites. Little ones that will burn up totally aren't a problem. However, satellites that have parts that aren't going to burn up nicely on re-entry need to be able to be redirected to the oceans. Imagine the amount of energy the 100 lb. chunck of flaming hot iron from this satellite is packing.

      If they could control this thing and bring it down when and where they wanted they could potentially do some interesting stuff. Like having it streak over the opening ceremonies at the Olympics. Or if the had REALLY fine control they could light the olynpic calderon with it instead of using the torch. That would be even better than the flaming arrow. Or they could drop it on Bin Laden's head. Ok, now I am getting silly.

      ps I am bitter because I submitted this exact article and had it rejected several hours before it appeared.

      • by nadaou (535365) on Wednesday January 30, 2002 @01:44AM (#2923683) Homepage
        If they could control this thing and bring it down when and where they wanted they could potentially do some interesting stuff. Like having it streak over the opening ceremonies at the Olympics.

        you've never met Mr. Murphy have you? You see, he's got this law..

        Gives new meaning to a 'messy' PR problem..

        'shotput from god kills thousands' or something for the headline..

        sigh. all too easy.
      • Any satellites put into orbit should be required to have the capability of being brought down safely.

        Where's the fun in that? Besides, you don't need any new laws, there are already existing laws that prevent people or companies (groups of people) from inflicting harm on citizens of the United States. This is all the incentive most satellite-launching organizations need to make sure their satellites come down safely. And for those that don't, they risk having million-dollar lawsuits and criminal charges brought against them if their satellite should strike someone due to negligence.

        ps I am bitter because I submitted this exact article and had it rejected several hours before it appeared.

        Get over it, yours was probably submitted AFTER the one that eventually got posted AND/OR it sucked compared to the one submitted.
      • Any satellites put into orbit should be required to have the capability of being brought down safely.

        I agree. However, this is extremely hard to enforce. What would the US government do if a foreign (Russian, Chinese, Japanese, French, you name it) satellite does not have this capability? 'Express their concerns' via diplomatic channels, or something less effective, I think. Clearly an international treaty would be required.

        Many satellites are used for military purposes, and a reliable re-entry system would require reductions in the satellite payload and efficiency or increase the cost. I doubt most nations are not willing to let some international treaty to compromise their military interests. Considering the fate of the ABM treaty, it is pretty clear that United States is not one of them. Enforcing such a treaty efficiently would also require pre-launch inspections of all satellites, including the military ones. How many nations with space capabilities would allow this?

      • since you could put the population of the world inside rhode island, I think the odds of it hitting someone is pretty slim. Possible just slim.
    • I wonder when this sort of thing will start to be a more common event."

      Considering the amount of space junk in orbit and the clutter and risk it represents, it's nice to see that some of this stuff is finally exceeding its orbital lifespan and is reentering.

      Of course, I'm not sure I'd want it ending up on /my/ house, but since we can't really make sure everyone sticks around to deal with their space litter (hello USSR?), I'm not sure what other options are available.

      *scoove*
    • The satellite is expected to land in Quassy, an uninhabited part of the Australian Outback.
    • Odds (Score:3, Informative)

      by jhines0042 (184217)
      Here are some stats for comparison

      Being killed in a car accident: one in 5,300
      Being a drowning victim: one in 20,000
      Choking to death: one in 68,000
      Being killed in a bicycle accident: one in 75,000
      Being killed by lightning: one in 2 million
      Being killed by falling debris from a satellite: one in 4 million
      Dying from a bee sting: one in 6 million
      Winning the current Power Ball Jackpot of $10 million dollars: one in 80 million
      • Re:Odds (Score:3, Interesting)

        by saider (177166)
        These probabilities are usually the computed from an analysis of death reports. As such these odds indicate that more people are killed every year by satellite debris than win the lottery. If twenty or so people win the lottery annually, then how many people die from satellite debris each year? This seems to be a more newsworthy event, but yet I never seem to hear about it.
      • Any links for those stats? I know that more people die from bee stings than satellites, so I was wondering how the odds for a satellite were better.
        • I think those aren't per annum chances, they're per event.

          Since there's millions more beestings per year than there are satellites coming down, that'd account for the difference in statisticss.
  • Hmmm (Score:2, Funny)

    by gessleX (454570)
    Crashing so soon?
    What version of Windows was it running?
  • by joekool (21359) on Wednesday January 30, 2002 @12:02AM (#2923271) Homepage
    time to hit yahoo for some pillows!
    ;-}
  • by ebbomega (410207)
    Gir exclaims Yayyyyyyy! We're doomed!

    This is amusing in that car-wreck sort of way. Who wants to bet that when this crashes on Mrs. Tingle's Rose Garden in Bummsville, Idaho and there's a lot of media attention, that the government is gonna spend lots of money to go up there and give these things emergency navigation systems so that they can easily fall on unsuspecting sea mammals instead of J. Random Human?
  • Free Taco? (Score:5, Funny)

    by toupsie (88295) on Wednesday January 30, 2002 @12:06AM (#2923292) Homepage
    I missed out last time, I suggest this time that Taco Bell uses a target the size of Rhode Island. I really, really want a Taco.
  • Its one thing to continuously crash things into Mars, we all hate those damn Martian scum anyways... But now we are talking about Earth! Stop forgetting about your unit conversions or carrying the 1, or else someone might get hurt!
    • And today, Lord Astronomer N'quth ended speculation on the strange flares coming from our neighbour planet by confirming these were due to volcanic activity.
      "The chances of anything coming from Terra", he said, "are a million to one."
  • This is definitely *not* an "act of God." So I wonder if my insurance policy will cover if it comes down on my house, car, wife, dog (just kidding - I don't have a dog)
    • Re:Insurance? (Score:5, Interesting)

      by Leven Valera (127099) on Wednesday January 30, 2002 @12:17AM (#2923357) Homepage Journal
      My homeowner's insurance actually covers impact by falling equipment, meaning telephone poles usually, but I guess satellites could be covered.

      LV
    • Check the small print - if its a HO-2 or HO-3 policy you are covered for 'falling objects', so a satellite (or meteor impact) would be covered. However, if the satellite is Nuclear Powered, you are not - anything atomic is a standard exclusion.
      Also if you are hit with a military satellite, that could be a grey area also - acts of war are not covered.
    • mine explicitly covers damage from "airplanes, including self-propelled missiles and spacecraft." (There's an exception for nuclear weapons detonation, but that wouldn't seem to apply in this case.)
  • by bo0push3r (456800) <boopusher@gmx[ ].uk ['.co' in gap]> on Wednesday January 30, 2002 @12:09AM (#2923314) Homepage
    with the number of objects we've put into orbit around our planet at an all time high and increasing constantly this will become more and more common. logic dictates that ultimately these things will make land in someone's yard (living room, white house, etc.).

    the real problem here is what to do about it...

    i propose using defunct home Internet appliances as projectiles. it would be extremely inexpensive and, when fired from a railgun at speeds in excess of 30,000ft/sec, these little beauties could easily eliminate a chunk of space debris weighing 100 or more lbs.
  • by Nick Smith (321087) <(ua.moc.enobew) (ta) (htimsn)> on Wednesday January 30, 2002 @12:10AM (#2923322) Homepage
    Q: What costs millions of dollars to produce and is guaranteed to crash back to earth?

    A: ABC's new Fall line-up...
  • Or do they mean no FUNCTIONAL onboard steering system? I don't know of many satellites that don't include manuvering thrusters. Orbits decay naturally and require slight adjustments over time.

    Of course, it WAS described as defunct, so I suppose I can give them some leeway on that.

    -Restil
  • by josquint (193951)
    OK... so these things have a fairly limited and predictable life span. And there's thousands of good sized objects up there that WILL fall(what goes up must come down, unless you put it waaaay up there)

    There REALLY should be a way to contoll the destruction better, instead of just letting it drop. Granted making it drop might be better, but this thing will still have some pretty good chunks hitting the ground. Why not design them to break up or be broken up more thoroughly. Somewhat similar to what an Indy Car does when hitting a wall.

    Putting explosives and the like would be somewhat risky, and designing weaknesses into the stucture might weaken it. But, having a 200lb chunk nail my house at mach 6 wouldn't be the best either :)
  • Food for thought (Score:4, Interesting)

    by Boiling_point_ (443831) on Wednesday January 30, 2002 @12:19AM (#2923363) Homepage
    Self-destruct mechanisms as a design feature for all sattelites...

    Could you design a sattelite in such a way that it could be destroyed remotely, ie. blown into small chunks that pose no danger to other spacecraft (are "blasted" towards Earth and therefore certain disintegration), while maintaining stability during launch/operation and not adding too much to the total weight?

    Devil's advocate:

    Who'd enforce it? Corporations won't pay extra for a very unlikely liability problem (until such a time that we're lobbing dozens of big things into space daily)

    What circumstances (other than system failure) would cause you to push the button - and if it had failed, who's to say it's pointed the right way and you won't shoot your comsat into the ISS?
    Sorry - just thinking out loud...IANARS

    • by afidel (530433) on Wednesday January 30, 2002 @12:45AM (#2923509)
      Blowing a satelite into small pieces is a VERY bad idea, as those pieces will go and run into functional satelites. Those satelites will fragment and soon you have a run-away chain reaction that might keep us out of space for decades.
    • by Goldenhawk (242867) on Wednesday January 30, 2002 @01:07AM (#2923580) Homepage
      >Self-destruct mechanisms as a design feature for all sattelites...

      As afidel wrote above (I'd mod him up if I had any points now), you don't want to do this to a defunct satellite.

      As you point out, it would have to pose no danger to other spacecraft. Well, the only practical way to do that is to ditch it in a controlled fashion. Any explosion involves a release of energy in pretty much all directions. Although some shaping of the charge can control the blast, you still blast some pieces in every direction. Each piece that does not hit the atmosphere enters its own orbit - risking collision with some other satellite.

      The proper solution, employed by almost all responsible satellite designers, is to allow enough extra fuel to deorbit the satellite. Of course, this depends on having CONTROL of the satellite. To guarantee this requires more redundancy - and more weight and fuel and complexity, etc. At the tens or hundreds of thousands of dollars a pound for launch costs, the designers usually opt for mission-suitable redundancy, and hope (and pray) that all the systems don't fail before they DO deorbit. And if they do start failing unusually fast, they'll deorbit early to avoid this kind of fiasco.

      Kind of ironic - I've seen some griping on /. in the past [slashdot.org] over deorbiting a still operational satellite. Well, WHY DO YOU THINK THEY DO IT? Purely to avoid this situation.

      You can't have it both ways, folks!
      • Each piece that does not hit the atmosphere enters its own orbit - risking collision with some other satellite.

        Even something hitting the atmosphere does not mean it will simply burn up or hit the Earth. The alternative possibility is that it can bounce off, into a different orbit.
    • Good idea but remember that every kilogram (or pound) in a space launch must be cost-justified as every one costs millions to lift into orbit. This isn't simply a matter of "would they use it wisely" but rather "would they pay millions of dollars to include a self-destruct payload if it meant leaving a major feature of the satellite behind." I agree that it's both a good idea and debatable whether corporations would support it, but I think their hesitations would be more related to launch costs.
    • Could you design a sattelite in such a way that it could be destroyed remotely, ie. blown into small chunks that pose no danger to other spacecraft (are "blasted" towards Earth and therefore certain disintegration)

      To do this you'd need a fancy system of shaped charges. You'd also need to have a functional attitude control system when you set them off. Also the chance of something reaching the ground intact is not simply a function of its size. Shape and composition also play a part.
  • Incoming! (Score:5, Informative)

    by James1006 (544398) on Wednesday January 30, 2002 @12:20AM (#2923372) Homepage
    Actually, debris entering the atmosphere (man-made and not) is a common occurrence. Happens everyday on some scale. It isn't just everyday a 3.5 ton one comes down :)

    I believe US Space Command/NASA/NORAD spends a ton of time tracking objects in close orbit, even very small ones the size of your finger.

    After all, anything going 17500 miles per hour hitting something like the space shuttle or Hubble or any other satellite (GPS, communications, spy/defense) wouldn't be pretty.

    Someone who worked for NASA at MSFC told me that they have actually had astronauts on the space shuttle change the shuttle's orbit slightly in order to avoid certain large pieces of debris.

    • Re:Incoming! (Score:2, Informative)

      by Y B MCSE (469234)
      After all, anything going 17500 miles per hour hitting something like the space shuttle

      Someone who worked for NASA at MSFC told me that they have actually had astronauts on the space shuttle change the shuttle's orbit slightly in order to avoid certain large pieces of debris.


      If you watch the news when the shuttle is up, notice it is ALWAYS flying backwards (except for reentry) pebble size objects ping it constantly and the windshields get so damaged they are replaced every launch ($40,000).

      Mission control plans the routes so that no human has to attempt the maneuvering you are speaking of. All happens far to fast.
      • Re:Incoming! (Score:2, Informative)

        by James1006 (544398)
        Wrong (Sorry).

        Quick google, straight from NASA:
        Source: http://www.wstf.nasa.gov/Hazard/Hyper/debris.htm

        "Larger particles (objects greater than 10-cm in diameter) are being tracked and catalogued by USSPACECOM radar. Spacecraft and satellites can avoid collisions by maneuvering around the larger debris. For example, when a space shuttle is in orbit, the USSPACECOM regularly examines the trajectories of orbital debris to identify possible close encounters. If a catalogued object is projected to come within a few kilometers of the space shuttle, it will normally maneuver away from the object."

        Also, further: http://see.msfc.nasa.gov/see/mod/modtech.html

        Scroll down on that page. Left side. Headline articles.
    • Re:Incoming! (Score:5, Informative)

      by man_ls (248470) on Wednesday January 30, 2002 @12:47AM (#2923517)
      True that. I've been inside NORAD and seen the satellite tracking facility (it's about 50 SGI Indigo and Indigo 2 workstations running a DOD-specific version of IRIX, with a second "hot backup" also used for training with identical hardware but a different room config a few floors down. (all that from only about 5 minutes in the lab...)

      It's pretty cool actually, you can open their anaylisis program and plot x; where x = the chronological number from 1 = Sputnik of the satellite launched, for a bunch of nice apogee/perigee/period/distance/elevation graphs. plot (some number I don't remember, and is probably classified anyway) plotted Mir, and the graphing was so accurate you could literally picture in your mind the space station flying around in closer and closer spirals until perigee=0 and reentry.

      But anyways-yes, they do track the stuff. And yes, they do course correct. A lot more than you might think too.
    • Actually, debris entering the atmosphere (man-made and not) is a common occurrence. Happens everyday on some scale. It isn't just everyday a 3.5 ton one comes down :)

      Though this is a fairly fragile 3 and a half ton object. It's not ias if it is a 3.5 ton lump of iron and nickel or solid rock.
  • OK.

    If this DOES start to happen with higher frequency the Star Wars will save us... right?

    We don't have anything to worry about because George W. is going to protect us from this stuff. :)

    It would be a REALLY great scandal.

    Bush and his defense contractor friends are not counting on anything actually happening. If something comes down and causes any damage this would put a BIG red mark on his face. :)

    Kevin
  • Warning. (Score:5, Insightful)

    by Score0, Overrated (550447) on Wednesday January 30, 2002 @12:28AM (#2923407) Homepage
    I know there's not a whole lot we can do about it ... but couldn't the media have given us a bit more warning. It's less than 30 hours from the CNN article to the earliest estimated reentry time.

    NASA's original press release [nasa.gov] was on the 16th Feb.

    Even that is a bit worrying. Did NASA only discover 11 days ago that their 3.5 tonne satellite was going to crash? It's not like they behave erratically, is it?
  • info (Score:5, Informative)

    by Alien54 (180860) on Wednesday January 30, 2002 @12:36AM (#2923462) Journal
    EUVE Archive [berkeley.edu]
    EUVE Home (UCal. Berkeley) [berkeley.edu]

    Info on satellite tracking here [satobs.org]. Track the orbit, and place bets on where it will land. (note, the farthest north is someplace in florida.)

  • by coupland (160334) <dchase AT hotmail DOT com> on Wednesday January 30, 2002 @12:39AM (#2923481) Journal
    If gravity is formed by areas of extreme density, I'm putting my money on it landing in Redmond.
  • Please hit our provincial government, please hit our provincial government, please hit our provincial government.

    Amen.
  • by Toomel (308985) on Wednesday January 30, 2002 @12:44AM (#2923504) Homepage
    Its okay guys..really. Bruce Willis and his buddies are training right now. There is no cause for worry!
  • Crashing? (Score:2, Funny)

    by tshak (173364)
    Crashing so soon?

    What version of Linux w/Gnome is it running?

    :-)
  • I find it somewhat disturbing that in the year 2002, after we've put men on other planets, taken photos of galaxies millions of light years away and split the atom, we cannot determine the path of a plummeting object.

    CNN (and other sources including NASA) are reporting a 9 hour window on when it could fall. With all the scientific minds and all the great algorithms we have, we can't determine when something like this will happen? Or is it that unimportant to bother getting out the slide rule and doing some calculations? And then there's where. A 1000 mile path that nobody seems to have any clue where it might land. We can't figure out a simple trajectory?

    Doesn't this disturb anyone that chunks of metal up to 100lbs is going to be dropping on our heads shortly? True, the chances of getting hit are probably a billion to one, but they say that about lightning as well. Well, it'll be a fun light show and we can always hope it lands in Redmond or somewhere insignifigant.

    liB
    • Can you tell me where a piece of paper dropped off a skyscraper will land?

      The weather in low earth orbit is just as unpredictable as the weather at the ground, and just as variable. The density of the atmosphere around satellites (and thus the drag force on them) can vary by an order of magnitude. If the satellite loses orientation (which it is essentially certain to as drag forces overcome tidal or powered stabilization) then its coefficient of drag changes as well, and unpredictably when it rotates. It may not even have just drag acting on it; even in orbit an angled surface can produce just as much lift as drag, and when the satellite hits the atmosphere its shape could produce more lift than drag.

      And of course, for every second by which the atmosphere delays reentry, the satellite has moved 5 miles in its orbit. 5 mi/s * 3600 s/hr * 9 hr gives a nice 160,000 mile strip of possible landing sites, crossing around and around the whole globe. If you'd like to gamble about the probability of something being hit by one of the chunks, though, I suggest placing your money on "no".
      • Can you tell me where a piece of paper dropped off a skyscraper will land?

        Apparently you can do this with a magic passport though.

        The weather in low earth orbit is just as unpredictable as the weather at the ground, and just as variable.

        If something is comming down from orbit the weather at all levels of the atmosphere

        It may not even have just drag acting on it; even in orbit an angled surface can produce just as much lift as drag, and when the satellite hits the atmosphere its shape could produce more lift than drag.

        Solar arrays are obvious type of object for generating lift. As a satellite is heated it may well be subject to forces from "outgassing".
      • Can you tell me where a piece of paper dropped off a skyscraper will land?
        Poor analogy.
        a better one would be, If I hurld a baseball off a skyscrapper, could you tell me EXACTLY where it will land.
        In which case the answer is YES within 5%.
        Same with the satalit, they know its speed, and direction, once they know its angle, the rest is just math. The weather, with the eception of extreme weather, will have little impact on an object entering the atmosphere at this speed. Yes I know it will be constantly slowing down, and it will be changing shape as t enters, but thats why its a 5% margin of error, or 95% accuracy.
  • by PsiPsiStar (95676) on Wednesday January 30, 2002 @01:30AM (#2923644)
    ... starlight, starbright, first star I see toni ... *thud*
    • Yet space agency scientists said there is little risk because most of the doomed satellite will burn up in the atmosphere.

      at least a little of the sattelite is going to end up hitting the earth, and it's going to be DAMN HOT!
  • by PsiPsiStar (95676) on Wednesday January 30, 2002 @01:47AM (#2923691)
    Considering how much it costs to send a pound of anything into space, it's too bad they couldn't just send it into geostationary orbit maneuver it to where a space station could get at it so they'd at least have the spare parts/metal up there.

    Of course, my closet is full of old computer parts, so you see how I think.
    • The International Space Station is at an altitude of 400 km. Geostationary orbits are more like 36000 km, which is far beyond the reach of the Space Shuttle, which would be the logical (i.e., only) choice for collecting space debris and transporting it to ISS.
    • Due to orbital mechanics, it would take about 15tons of gas to move this 3.5 ton spacecraft into geosync orbit. Any when you get it there, it becomes like all those 5.25" floppy drives in your closet - i.e. obsolete, worn out and useless. i.e, the wrong sort of stuff. 3.5 tons of rocket propellent in GEO would be worth more than than the metal - many communication satellites up there eventually are retired due to running out of gas, even though the electronics has a few years life left in it. Remember, commsats are the only thing really making decent $$$ in space.
  • by xee (128376)
    Dude, it's freaking Skyfall Day! They actually had a block party for that sorta thing. I really wish some network would re-run the series again. it r00ld.
    • Dude, it's freaking Skyfall Day!

      Get out your umbrellas and lawnchairs!

      I really wish some network would re-run the series again.

      The hell with that. I want it on DVD already.

  • by Performer Guy (69820) on Wednesday January 30, 2002 @02:23AM (#2923776)
    Space junk deorbits all the time. It just doesn't get the same publicity, some of the junk includes upper stage boosters including tons of fuel and a payload. The amount of rock naturally falling out of the sky is still more than the deorbiting garbage but nobody seems to worry about that, despite it destroying the occasional roof or car like these incidents:

    http://www.space.com/scienceastronomy/astronomy/ pe rseids_shower_sidebar_000809.html
    • It just doesn't get the same publicity, some of the junk includes upper stage boosters including tons of fuel and a payload.

      IIRC this sort of thing happened with the "Sea Lanuch" system. All the innovative bits worked fine, but the final stage of the rocket was a dud.
  • by DriceX (210607)
    Could all of those people who built Y2K shelters have a chance at mocking those who didn't?
  • Some perspective (Score:2, Interesting)

    by lexcyber (133454)
    Did you know that just about all countries send
    up thousands and thousands of weatherbaloons
    in the sky, every day. And you dont hear them
    killing people left and right?

    That is metal intstruments that weights a few
    pounds. Hitting the ground in 200-300km/h
    that is more then enough to kill a man or
    destroy a car etc. etc.

    So, I guess it wont be such a big problem.
    Now, or in the future.

    afaik. there has been one or two incidents in
    30 years in sweden of thoose landing in urban
    areas.
    • Did you know that just about all countries send up thousands and thousands of weatherbaloons in the sky, every day. And you dont hear them killing people left and right?

      It's not unknown for bits and pieces to fall of aircraft. Sometimes without even being noticed until a maintenance worker takes a look at the plane.
  • J-Track 3D (Score:3, Informative)

    by Kwirq (43822) on Wednesday January 30, 2002 @04:30AM (#2924100) Homepage
    While we're talking about tracking satellites,

    NASA's got a cool little Java applet [nasa.gov] you can play with to see the satellites and their orbits.

    It's a simulation based on posted data, I gather, rather than any kind of tracker, and I'm sure there are dozens of black satellites not listed, but it's still very neat. You can zoom in/out and around the earth, pick specific satellites from categories, changes the time speed, etc. There's also all the favourites such as the shuttle (when it's up), the ISS, Mir, Hubble, COBE, etc. You can also load a web page with more info about any given satellite, such as when it was launched, what it carries, and so on.

    Enjoy!

  • Again, just 20 minutes into the future, the series Max Headroom had a bit where there was an annual festival called "Skyfall", that in the city had sort of replaced the Mardi Gras as the big thing of the year.

    The highlight of the celebration was that each of the networks and others would intentionally down their retired satalites on the same night each year, producing an intentional light show of shooting stars (as seen from earth).

    Silliness abound (inspired by the Skylab incident) about people walking around with metalic umbrellas and the like...

  • Extreme Ultraviolent Explorer, and all sorts of images started to form in my head, mostly related to Alex and his old droogs [imdb.com] in combination with a (in)famous browser [microsoft.com].

    I'm pretty happy I read it wrong. Although Microsoft never seem to hesitate to give us "some of the old in-out-in-out" whenever we dare to walk in the wrong parts of town.

Byte your tongue.

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