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Space Science

How We Knew AL00667 Would Miss Earth 290

jefu writes "In January there seems to have been an incident in which it was thought that an object (asteroid) in space might have hit the earth within a couple of days of being spotted. It did miss, though. This story (from NASA/Ames) talks about the discovery of the object and the process that astronomers went through to determine if the asteroid was or was not a threat."
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How We Knew AL00667 Would Miss Earth

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  • Wow (Score:3, Insightful)

    by rholliday ( 754515 ) on Tuesday February 24, 2004 @06:14AM (#8371761) Homepage Journal
    I'm glad they're so confident. I, for one, find the thought terrifying. :)

    Too bad they already made the (17 versions of) the movie about this. It's a nice story.
    • Re:Wow (Score:5, Funny)

      by asbestos_tophat ( 720099 ) on Tuesday February 24, 2004 @07:00AM (#8371890) Journal
      The earth is hit by material every day. A planet killer meteor hits about once every... Wait! We are still here? hmmm, that must mean what?...

      Besides everyone knows the world ends in 2017 due to old UNIX Y2K17 bug & embedded NT licence key expiry causing cascade failure of ICBM guidance systems. ;-) lol I will need Lead underpants soon... ha ha ha

      Relax, Statically speaking you will probably win the lotto 12 times, get struck by lighting 302 times, and die from stress or cancer 240 million times... likely to happen long before then... ;-)

      • Re:Wow (Score:3, Insightful)

        by Anonymous Coward
        Wouldn't it be a bit difficult for me to die of cancer 240 million times? I can understand once but...
      • Re:Wow (Score:2, Insightful)

        by !3ren ( 686818 )
        Statistically speaking, are we talking individually or as a population?
        In the latter case, your statistics do not give me confidence :)
      • by waterbear ( 190559 ) on Tuesday February 24, 2004 @10:47AM (#8373127)
        Let's just get this straight: according to the article, the initial data were of low precision, they implied a very large uncertainty in the asteroid's trajectory. (In the event, it wasn't even a near-miss -- it was millions of km off, several times the moon's distance.)

        The large uncertainty meant that at any one moment before the conceivable (but very unlikely) arrival of the body at or anywhere near the earth, there was a very large area of uncertainty, in which the asteroid's actual point of arrival would be one tiny and uncertain spot, and the possible trajectories leading to earth would be represented by another tiny blob (tiny relative to the whole area of uncertainty), most probably located very far away from the spot containing the real asteroid.

        Calculations on real computers often represent an area of uncertainty like this by a nominal position that is very roughly at the centre of the area of uncertainty, accompanied by a measure of the size of the area of uncertainty.

        The fact that one can physically read from the printed result and see that nominal position separately from its accompanying measure of uncertainty, because of the way the figures are presented on screen or paper, that does not give the nominal position any reality.

        It happened that the nominal position first calculated in the case of AL00667 would have been (if of zero error) a trajectory heading for earth. But it wasn't of zero error, nor even close.

        The whole scare looks like an artifact of the way in which uncertain results involving a continuum are presented using discrete digits.

        -wb-
      • Re:Wow (Score:4, Funny)

        by ClubStew ( 113954 ) on Tuesday February 24, 2004 @10:58AM (#8373236) Homepage
        I will need Lead underpants soon

        Don't forget the tin foil hat to gaurd against the aliens that will likely take advantage of the situation, and an accurate firearm to shoot the ensuing radioactive zombies in the head.

    • Re:Wow (Score:4, Interesting)

      by uberjoe ( 726765 ) on Tuesday February 24, 2004 @01:29PM (#8374978)
      I'd like to see a movie based on Lucifer's Hammer. It's more about life after the comet hits than the struggle for bruce willis to blow it up.
  • timing... (Score:5, Funny)

    by menn0nite ( 699138 ) on Tuesday February 24, 2004 @06:15AM (#8371765)
    perhaps AL00667 creates MADMEN [slashdot.org]
  • Interesting... (Score:5, Insightful)

    by Spazmasta ( 744225 ) on Tuesday February 24, 2004 @06:16AM (#8371771)
    that most people didn't hear about the asteroid until long after the near-miss was over. Seems to bring up the old argument of whether it'd be better to inform the public and try to do something about it or keep it under wraps and possibly die in blissful ignorance...
    • by qkw ( 755948 ) <qkwozz AT bjcomics DOT com> on Tuesday February 24, 2004 @06:20AM (#8371781) Homepage
      better yet, send bruce willis up there, and don't tell anyone. That way he might get some money for it if it works and he returns, or we all die, or (the optimal solution) he diverts the asteroid and goes hurtling off into space with it..
    • Re:Interesting... (Score:5, Insightful)

      by retards ( 320893 ) on Tuesday February 24, 2004 @06:39AM (#8371844) Journal
      Well, yes, I guess you will die blissfully if you happen to be very near impact. Otherwise you can look forward to drowning in a tsunami, starving in the coming 5-year winter or just die at the looting of the local convenience store once the news breaks (duh, saltwater rain, 4 weeks of darkness, complete failure of all infrastructure, etc.).

      It is a totally futile to even discuss what should be done if we are going to get hit, since there is nothing we can do about it at the moment. If the death of 80% of the worlds population and the fall of all governments is nigh, it hardly matters how people die or how the governmenst fall. It only confuses the real issue: how the hell are we going to fund a global defense system instead of funding luxury for 10% of the planet.
      • by midg3t ( 724635 ) on Tuesday February 24, 2004 @08:18AM (#8372098) Homepage

        Slashdotters can continue to sleep comfortably with the knowledge that TCP/IP is designed to withstand such an event; lets just hope there's a backup of the /. backend in case its server(s) get struck, shorted by the tsunami, or looted by the local villagers.

      • by Anonymous Coward
        "how the hell are we going to fund a global defense system instead of funding luxury for 10% of the planet."

        Someone's been playing an awfull lot of Civilization. Parhaps if we found another type of luxury on one of our contries squares. =)
      • If anarchy is ever declared, I think the best bet would be to get about thirty or forty people together and steal a couple of school busses. Then you could take over WAL*MART ( one of the mega variety with the grocery store ) You would then park the school busses in front of the entrances and post sentry's on the ramparts of the well stocked ( with guns, ammo, food, supplies ) cement, fort like building. The parking lot would act as a killing field for any would be interlopers.
        • Re:Fort Wal (Score:3, Insightful)

          by Bingo Foo ( 179380 )
          If anarchy is ever declared...
          ...ask under what authority the "declaration" was made.

        • Re:Fort Wal (Score:5, Funny)

          by magarity ( 164372 ) on Tuesday February 24, 2004 @12:28PM (#8374296)
          Don't know about where you are but around here the Walmarts sell guns and ammo. And there are already a good 30 to 40 employees already inside. Good luck taking over the place.

          So in the event of a meteroid strike, I for one will welcome our new Walmart line level employee overlords... As opposed to the Walmart corporate type overlords we have now.
    • by Hektor_Troy ( 262592 ) on Tuesday February 24, 2004 @08:08AM (#8372070)
      most people didn't hear about the asteroid until long after the near-miss was over
      Near miss? What kind of fubar misuse of a word is that? It's a near-hit.

      A collision is a near-miss.

      *boom* Look. They nearly missed

      Appologies to George Carlin :-)
      • Re:Interesting... (Score:3, Interesting)

        by JeffSh ( 71237 )
        i think the real interpretation of the compound word "near miss" is that it was near, yet still a miss.

        being critical of the term "near miss" being mutually exclusive is infact a mis-understanding of the term.
        • by stienman ( 51024 ) <adavis@@@ubasics...com> on Tuesday February 24, 2004 @11:19AM (#8373456) Homepage Journal
          So you're saying that he had a "near-misunderstanding" of the term "near-miss"?

          Right. "We had a near miss event last night." In theory, as you indicate, you could assume that "near" and "miss" both modify "event," but it is common in American English to modify modifiers, so that near modifies miss, and "near miss" as a phrase modifies "event."

          Either way it is, at best, a near misleading phrase with a near threatening probability of being near misinterpretted. You should stay far away from such a near confusing phrase and stick to straightforward language.

          Good enlgish makes for bad headlines, though.

          -Adam
    • Re:Interesting... (Score:4, Interesting)

      by pkaral ( 104322 ) on Tuesday February 24, 2004 @08:47AM (#8372212)
      that most people didn't hear about the asteroid until long after the near-miss was over. Seems to bring up the old argument of whether it'd be better to inform the public and try to do something about it or keep it under wraps and possibly die in blissful ignorance...

      Using utilitarian calculations, you can actually compute whether or not the expected consequences of informing are preferable to the expected consequences of secrecy. It would go something like:

      Inform if EU(i) > EU(s)
      where
      EU(i) = p(h) * (1 - p(prev)) * U(knowing)
      EU(s) = (1 - p(h)) * U(nondisr)

      where
      EU(i), EU(s) are the expected utility functions of informing and keeping secret, respectively
      p(h) is the probability of a hit
      p(prev) is the probability that a hit could be prevented if known to the public
      U(knowing) is the value people would place on knowing in advance if they were going to be dead tomorrow
      U(nondisr) is the value people would place on the avoided distruption of a global panic (the economic + emotional "costs" saved)

      Thus, whether to inform depends on:
      - How certain are you that the asteroid will hit?
      - How big do you think the disruption will be if word of potential impact spreads?
      - Is there anything you can do, given that it is going to hit?

      I think the first one is really important. It has repeatedly been shown in research that people do not react rationally to probabilistic information. Thus, telling the public that "there is a chance that an asteroid could hit us", even when qualified by a quantification of the probability to the best of our knowledge, could actually lead to a greater mis-assessment of the risk than if nothing were said of it.

      This is, of course, not a question of probabilistic and utilitarian calculations. There is a "right to information" aspect to it, as well. A good formulation would be "where is the borderline between 'creating unneccesary panic' and 'respecting people's right to know'". I would say that if the expert is worried to the point of personally taking significant action based on the information, such as buying emergency supplies etc., then he should inform the general public.
  • by IntelliTubbie ( 29947 ) on Tuesday February 24, 2004 @06:18AM (#8371774)
    So many to choose, since it was an entire episode, but this one seems appropriate:

    Sounds like the doomsday whistle! Ain't been blown for nigh onto three years.

    Cheers,
    IT
  • MADMEN (Score:2, Funny)

    by termos ( 634980 )
    Where is my MADMEN when i need one?
  • by arvindn ( 542080 ) on Tuesday February 24, 2004 @06:22AM (#8371788) Homepage Journal
    ...but its practically certain we're going to be hit by an asteroid real soon.

    Else we'd be meeting all the time travelers from the future :)
  • No problem! ... Bruce Willis will bust us out! ... Our super-geniuses will come up with a 5min to deadline plan and blast this bugger to pieces! ... It won't hit us anyway, because it did not hit us up to today.

    Tell me Mr.Politician, what is more important: Survival of mankind or playing the powermonger game with your politician-buddys?

    I say, if politicians (which are by the way trusted with OUR FATE!) behave like they do today they are gambling with the chance of survival for the entire human race. Thi

  • by Gopal.V ( 532678 ) on Tuesday February 24, 2004 @06:27AM (#8371804) Homepage Journal
    Onlooker1: It would mean the end of life as we know it ?
    Scientist: No, but it might burn up a few cities and destory 70% of the humans ... but we don't really see a threat to the human species.
    Onlooker2: So I'd be dead ?
    Scientist: But the people left alive will have an excellent chance of survival due to the systematic culling of slashdot trolls .... not to mention rabid money hungry CEO types... along with a few cities as collateral damage.
    Onlooker1: Why did you keep it under the wraps ?
    Scientist: We were kinda hoping it would slag Sanford Wallace in location... and have the Pope claim it was divine intervention
    Onlooker3: What about SCO ?
    Scientist: Looks like the next one from Kuiper belt would do that clean

    PS: maybe you should read "God's Debris" to be frightened by Slashdot.
  • by Aceticon ( 140883 ) on Tuesday February 24, 2004 @06:27AM (#8371806)
    After buying a milion cans of baked beans, a zillion beer cans and 10 years worth of Playboy magazines (only for historical purposes, of course) they waited it out for a couple of days in an underground bunker.

    Since they didn't felt any shake, it was proven that the meteorite had missed the Earth.

    It was further proven that a zillion cans of beer barely lasts a couple of days and that having a million cans of baked beans is pretty useless when you forgot to bring a can-opener

    One thing of note is that somehow, 10 years worth of Playboy magazines disapeared without a trace.

  • by Anonymous Coward on Tuesday February 24, 2004 @06:30AM (#8371818)
    Short Warning Times

    Back to Archive
    Article Posted: February 19, 2004

    By: David Morrison

    For the story of AL00667, which briefly masqueraded as an asteroid that would hit the Earth within two days of its discovery, read on.

    February 19, 2004 Short Warning Times

    Following is information on the small asteroid known last January 13-14 as AL00667. A preliminary analysis of the discovery data for this object yielded a possible impact with Earth in less than 2 days time -- a situation not encountered previously in the Spaceguard Program. Although we knew at the time that such a prediction of imminent impact was improbable, a collision could not be ruled out. And if a possibility of an impact in 2 days existed, what should we do about notifying governments or the public? The story of this situation on January 13, 2004, is included as part of a paper by Clark Chapman (Southwest Research Institute) presented on February 22 at the Planetary Defense conference of the AIAA (American Institute of Aeronautics and Astronautics). Several paragraphs taken from this paper are reproduced below. Following these quotes from Chapman's paper are additional quotes from a letter Brian Marsden (Minor Planet Center) wrote to CCNet on 14 January on the same subject. Finally, there is a statement posted on the website of the IAU (International Astronomical Union) discussing what lessons we should draw from the story of AL00667, and how such a situation might be better handled in the future.

    Asteroids never cease to surprise us. We may never encounter a situation just like this again, but we are fairly sure to have other crises as the rate of discovery of NEAs continues to increase.

    David Morrison

    FROM CLARK CHAPMAN'S AIAA PAPER "NEO IMPACT SCENARIOS"

    presented February 22, 2004

    "Just last month (January 2004) perhaps the most surprising impact prediction ever came and went, this time out of the view of the round-the-clock news media. It illustrates how an impact prediction came very close to having major repercussions, even though -- with hindsight -- nothing was ever, in reality, threatening to impact. It is a story of success in that the impact prediction was nullified in record time, less than half-a-day, but the success was accomplished through a set of ad hoc, unofficial, and often unfunded activities and relationships, although assisted in major ways by the official infrastructure, such as it exists (the LINEAR Project, the IAU Minor Planet Center, and the NASA NEO Program Office).

    "About 36 hours before President Bush's planned speech at NASA Headquarters on future American space policy, the Lincoln Near Earth Asteroid Research (LINEAR) observatories in New Mexico routinely recorded four images of a moving object. Half a day later, on Tuesday, January 13th, these data were sent (as part of the daily submission of data) to the Minor Planet Center in Cambridge, Massachusetts. Just before going to dinner, MPC research Tim Spahr ran the data through standard software to generate a nominal ephemeris for the new object. These are posted on the publicly accessible NEO Confirmation Page (NEOCP) so that amateur and professional asteroid astronomers around the world might be able to follow up on the LINEAR observations that night. It is through such follow-up astrometry that NEO orbits can be refined so that the object is not permanently lost. Spahr posted the ephemeris, based on LINEAR's four detections, on the NEOCP under the designation AL00667, along with ephemerides for several other recommended targets. Less than an hour later, a European amateur astronomer, Reiner Stoss, went to the NEOCP and noticed a curiosity: AL00667 was predicted to get 40 times brighter during just the next day, meaning that it was going to be six times closer to the Earth! He expressed his amazement on Yahoo's MPML (Minor Planet Mailing List) chatroom on the internet.

    "Professional asteroid researcher Alan Harris happened to be monitoring the chatroom and noticed the strange
  • by Effugas ( 2378 ) on Tuesday February 24, 2004 @06:33AM (#8371823) Homepage
    In the past fifty years, we have started to gain the technological capability to detect potential collisions with asteroids.

    That does not make such a collision more likely in the next fifty years -- or hundred and fifty, or fifteen hundred. Significant and successful collision are _rare_, much rarer than earthquakes, tornados, or even human-caused meteorological effects (as in weather systems, not meteors).

    It doesn't matter if we can see "just how close we came". It matters that we know, empirically, that there are vastly more pressing concerns.

    What I don't want to see is an orbital weapons platform deployed under false premises. If the pretenses are true, that's a different story. Just don't tell me its to shoot down asteroids!

    --Dan
    • by Jhon ( 241832 ) on Tuesday February 24, 2004 @06:50AM (#8371869) Homepage Journal
      It seems like you are suggesting that this new technological ability to detect NEO's and possible impacts as being similar to the "Boy who cried wolf" fable.

      The problem is, as we all know, the wolf finally did arrive one day...
      • Please be advised that we are raising the Asteroid alert to code orange--high from yellow--elevated. This is due to intelligence that there may be big rocks nearby planning on heading in our general direction. Please be on the alert and double-check your umbrellas.
    • by Eivind ( 15695 ) <eivindorama@gmail.com> on Tuesday February 24, 2004 @07:12AM (#8371922) Homepage
      Sure. We know the chanses are low. Allthough we don't know exactly how low. We *do* know that in the last century alone we've had atleast a few impacts big enough that if they had happened to hit a major city rather than (for example) the tundra in Siberia, tens of thousands of dead would result.

      We also know that major impacts, the sort that changes the climate over the entire globe and causes mass extinction of species has happened atleast on a few occasions.

      But we don't really know enough to say anything about the true risks. For that reason alone, the first nice thing to do would probably be to increase funding for telescopes, radars and other instruments for better accessing the real risk. That is not a very expensive proposition, as this is an area that is very lowly funded today, a little bit of extra cash will go a long way towards establishing the real risks.

      If we should do anything more depends on the risks and the costs of potential defences. It's a cost/benefit calculation.

      You are rigth that ICBM-interception-systems are irrelevant for this purpose. All realistic systems for doing something about asteroid-impacts rely on the fact that a small change to the orbit of the thing a long distance from earth will result in a major change, enough to miss the earth, by the time it gets here. Changing the orbit in the last few hours is going to be impractical, it'd require huge amounts of energy. Sligthly more practical migth be blowing the thing up, which would result in a large number of smaller impacts instead of a single big one.

      To stop a ICBM you need to hit it with, say, the explosive force of a hand-grenade. That's not going to cut it if you want to blow apart a asteroid of extinction-threathening size.

    • What I don't want to see is an orbital weapons platform deployed under false premises.

      Yes, because putting weapons in an orbital platform is so much cheaper and more effective than housing them in silos in Kansas. Who knows what evil could come if Rumsfeld got his hands on a large, unprotected orbital concentration of weapons from which missiles could be launched only in well-described orbits that could be easily intercepted.

  • more info (Score:4, Informative)

    by gsmb ( 658454 ) <daxiccb@NoSpAM.gmail.com> on Tuesday February 24, 2004 @06:39AM (#8371841) Homepage Journal
    try this link for more info http://www.hohmanntransfer.com/mn/0402/09.htm
  • Only 30 metres? (Score:5, Informative)

    by Zog The Undeniable ( 632031 ) on Tuesday February 24, 2004 @06:46AM (#8371853)
    That's about the size of the Tunguska object (probably a comet, since it exploded in mid-air and didn't leave a crater). Enough to make a mess of a big city or a pretty impressive tsunami, but not enough to wipe out mankind.
  • by EasyTarget ( 43516 ) on Tuesday February 24, 2004 @07:21AM (#8371938) Journal
    I find the number 667 Highly suspicious..

    Is number 666 ever issued? A lot of numberiung systems miss this one out, in order to keep the religeously insane from freaking. For instance the UK number plate authority stopped using it a few years ago after complaints from some quarters.

    So my real question is: Would this have -actually- been AL00666?

    Spooky...
  • by distributed ( 714952 ) on Tuesday February 24, 2004 @07:49AM (#8372014) Journal
    Exciting !!
    And maybe my neighbours underground bunker would have finally proven to be useful for things other than coding marathons...

    This would also be one hell sure way to get rid of windoze once and for all... only something as distributed as open-source software can survive such a catastrophy... wouldnt it be amazing if entire source code of windows was lost. wow !

    Now compare that to the linux source present on millions(?) of computers all over the world. Reminds me of the phoenix...

    tisk tisk..
    (warning: seriousness levels dangerously low)
  • Animation (Score:5, Informative)

    by jmichaelg ( 148257 ) on Tuesday February 24, 2004 @08:04AM (#8372058) Journal
    Here's an animation [demon.co.uk] of the object. The link [yahoo.com] to the yahoo egroup discussion is also worth looking at. The discussion morphs from everyone thinking it's a joke post to realizing that the asteroid exists. It's an interesting log of people coping with uncertainty.
  • by ozbird ( 127571 ) on Tuesday February 24, 2004 @08:37AM (#8372152)
    I'm waiting for the follow up article: "The Slashdotting that hit without warning."
  • ... Much like the server with the article, the Asteroid was slashdotted causing it to malfunction and miss the earth.
  • What if Iron asteroid 1/2 km in size plunges into earths atmosphere? Would that not have a significant impact?
    • by CXI ( 46706 ) on Tuesday February 24, 2004 @10:44AM (#8373099) Homepage
      An asteriod 2" in size would be a significant impact if it hit you on the head! However, they can't watch EVERYTHING. They have to draw the line somewhere. 1km seems to be the size needed to possibly wipe out all life on Earth. Yes, 1/2km would do a lot of damage and kill a lot of the population of Earth, but some would still survive the initial impact. I would assume once all the 1km NEOs are charted by 2008 that they would move on to the smaller ones. Also, as shown by this article, they found a 30m and now know its orbit. It's not like they are just throwing out the data for objects smaller than 1km if they happen to find them. Such small objects, however, are not the focus of the search.
  • by Jesus 2.0 ( 701858 ) on Tuesday February 24, 2004 @10:28AM (#8372956)
    We were lucky this time, but it is clear that we need to do something about such threats. Here is what I propose:

    We build a nondescript isosceles triangular spaceship, controlled by one man with a joystick. Left and right rotate the ship, up thrusts the ship forward, and down, well, down depends upon your configuration. Optionally, it could throw the ship through hyperspace to some other random point in space, or else it could put deflector shields up around the ship.

    In addition to the joystick, the ship's pilot should have access to a red button (it must be red). Pressing the button should cause balls of energy to shoot out of the front of the ship, capable of breaking apart large asteroids, and destroying small ones. Pressing the button should also make a "PCHOW!" sound.

    It is our clearest and best long-term option.
  • AL00667 is not the number of the beast; it was off by one. Ergo, it would not be the one to end the world.
  • Good book (Score:4, Informative)

    by Squidbait ( 716932 ) on Tuesday February 24, 2004 @10:58AM (#8373241)
    For a great novel about asteroid armageddon and the resulting collapse of society, read "Lucifer's Hammer" by Larry Niven and Jerry Pournelle. It's slow for the first half, but man, once that asteroid hits, it's sweet, sweet chaos.
  • by mmerlin ( 20312 ) on Tuesday February 24, 2004 @11:39AM (#8373701) Homepage
    If it was AL00666 the doomsdayers would've been going nuts about how this is the event that will wipe out all of humanity.

    AL00667 reminds me of that "neighbour of the beast" joke ;)
  • by Balrogg ( 466250 ) on Tuesday February 24, 2004 @01:48PM (#8375211) Homepage
    It seems to me that over the last few years I have heard a LOT of reports of asteroid near-misses - much more so than in the 80's or 90's. Unfortunately, I think it's going to take an asteroid/comet impact, over a population center, before the humans "in power" even begin to "get it."

    Recent movies aside, the thought of a HUGE rock (or solid chunk of iron) falling from the sky, is so completely beyond the experience of most humans, as to be practically ludicrous.

    "I would sooner believe that two Yankee professors lied, than that stones fell from the sky." - Thomas Jefferson (supposedly)

  • by Animats ( 122034 ) on Tuesday February 24, 2004 @04:47PM (#8377535) Homepage
    This incoming object was detected by GEODSS [af.mil], the Ground-based Electro-Optical Deep Space Surveillance System. This is one of those once-secret Cold War developments that really worked.

    GEODSS first came up in 1982. It consisted of four sites (three today, budget cuts) worldwide, each with three 1-meter telescopes. The whole system is computer-run and reports to NORAD automatically. This was the beginning of automated astronomy.

    The telescopes scan the whole sky every night, subtract out everything in the star catalog, and report unknown objects. New satellites and space junk are found this way. Even dark objects that occult stars are noted. There's also a more elaborate USAF site on Maui with even bigger computer-controlled telescopes.

    Some of the sites have lasers (Maui definitely does) and can illuminate their targets using one telescope while looking at it with another. This allows time-of-flight ranging, photography of dark objects, and determining whether a satellite has cameras. But illumination is only useful for near earth satellites; it doesn't help with asteroid search.

    Asteroid search is a spare-time activity of one of the GEODSS sites. They continue their real job for the USAF, looking for anything near the Earth that shouldn't be there.

    The GEODSS hardware was updated in 1999, with better sensors, new computers (the 20 racks of PDP-11 hardware had to go), better positioning accuracy, and some infrared capability for working around cloud cover. The original main optics remain in use.

    Your tax dollars at work.

  • Decisions (Score:3, Funny)

    by euxneks ( 516538 ) on Tuesday February 24, 2004 @05:18PM (#8377877)
    and the process that astronomers went through to determine if the asteroid was or was not a threat.

    Scientist: Heads or tails?

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