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Space Science

2004 MN4, Even Higher Probability 524

Posted by timothy from the keep-your-will-in-order dept.
phreakuencies writes "Worried since the recent post about the MN4 2004 asteroid, I added a bookmark to its 'impact risk' section at NASA. The asteroid started as having a 1/233 probability of hitting earth. Later it raised to 1/63. Daily computations made on 25 Dec raised its chances up to 1/45. Optimists can now say it has a 97.8% probability of missing earth." And Veteran writes " NeoDys offers the 'Orbfit' software package (source code released under the GPL) which can be used to get a pre-release view of the situation with Asteroid 2004MN4."
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2004 MN4, Even Higher Probability More

2004 MN4, Even Higher Probability

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  • Party like it's 2099 (Score:5, Informative)

    by IO ERROR ( 128968 ) * <error.ioerror@us> on Saturday December 25, 2004 @05:32PM (#11182190) Homepage Journal
    And now it's 4 on the Torino Impact Hazard Scale [nasa.gov].

    The way I see it, we've got about 24 years to party before the world ends. Have another glögg [finland.fi]!

    Seriously, if it hits 5 or greater on the scale, then we'll have reason to really worry. In the meantime, it's sufficient to just watch and see what happens. As phreakuencies pointed out, right now there's a 97.8% chance of absolutely nothing happening.

    • I guess I don't need to worry about my social security afterall!!!

    • Re:Party like it's 2099 (Score:5, Interesting)

      by Zocalo ( 252965 ) on Saturday December 25, 2004 @06:20PM (#11182388) Homepage
      Talking of the Torino scale, does anyone have any idea at what percentage probablility of impact it would move up to the orange (threatening) section of the scale? As far as I can tell, both the orange and red (impact!) sections are based more on the predicted amount of damage rather than likelihood of a collision, so I'm guessing it's pretty high. Also, assuming that the estimated size and consistency of the object don't change, it looks like an object would not be given two separate orange or red scores. If that's the case then I'm guessing that if MN4 is going to hit us it'll go to five, then eight based on a play with the damage predictor.

      In any case, we have 24 years and it's not *that* big. Plenty of time to nudge it off course with some of those surplus nukes we have lying around if it is going to hit...

      • Re:Party like it's 2099 (Score:4, Insightful)

        by discogravy ( 455376 ) on Saturday December 25, 2004 @09:09PM (#11182988) Homepage
        Plenty of time to nudge it off course with some of those surplus nukes we have lying around if it is going to hit...

        This has been covered before, but the problem with hitting an large object hurtling towards something with a nuke is that afterwards you have a lot of much smaller hurtling bodies which are now radioactive.

        • So hit it in two years or so. (about the fastest NASA could move I guess) Use a big nuke, if it is only 1/4 mile or so in diameter, that should completely shatter it[1]. And in 22 years or so the debris cloud should be about the size of the sun, and so little of it would hit the earth that it would hardly qualify as a good meteor shower. Much of the worst radation should be gone by then too.

          [1]If it is solid iron it won't shatter, just get thrown off course. But then it won't hit us at all - problem solve

        • Re:Party like it's 2099 (Score:3, Interesting)

          by alexo ( 9335 )
          > the problem with hitting an large object hurtling towards something with
          > a nuke is that afterwards you have a lot of much smaller hurtling bodies [...]

          which tend to burn on entry into the atmosphere.

        • Re:Party like it's 2099 (Score:4, Interesting)

          by ErikZ ( 55491 ) on Sunday December 26, 2004 @03:33AM (#11183962)
          sigh.

          Step one: Send out the bigass nuke right now. Put it on one of those ion engine crafts.

          Step two: Nail the trajectory down to 99% accuracy.

          Step three: Figure out the best way to deal with it. Have it pass by the earth into the sun? Have it slam into the moon? Is it possible to slow it down enough to put it into a stable orbit and mine it for resources later?

          Step Four: Once the calculations are done, send the course corrections to our bigass nuke to put it exactly where we need it, and to detonate when we want it to. You don't hit the asteroid directly. You just get close enough and nudge it. This is why you sent the nuke so early, over time, a small nudge adds up to a huge course change.

          Step Five: Placate the general public who were hoping they would have to send a mining team up in a risky yet heroic venture to save the earth.
      • does anyone have any idea at what percentage probablility of impact it would move up to the orange (threatening) section of the scale?

        I think it would take an election.

      • This page shows the dividing line, [nasa.gov] the probability needed to bring one from Torino 4 to Torino 5 depends on the kinetic energy as well. The current energy estimate I see at the NASA 2004 MN4 site [nasa.gov] is 1.6e3 MT, which puts us about (I'll guess here) a fifth of the way from 1e3 to 1e4 (as 1.6^5 = 10.48576, love them powers of two), so it's about 6/15ths (2/5ths) of the way between 1e2 and 1e5 MT, the upper bound of the Torino 4/5 box. It's kinda hard to figure how things transition on the probability scale

    • Let's say that the thing will hit (Score:5, Interesting)

      by ArcticCelt ( 660351 ) on Saturday December 25, 2004 @06:30PM (#11182427)
      Let's say for a moment it is confirmed that the thing will hit. Then we will have to determine where its going to hit. We know that damages will only be localized so if it is calculated that the asteroid will fall on an area populated by not so industrialized countries I am really curious how the world will react.

      Do powerful countries will prefer to do nothing to avert making a mistake that could possibly send the asteroid on their head?

      What could possibly do a small country in africa if nobody wants to help them?

      • Re:Let's say that the thing will hit (Score:5, Interesting)

        by Zocalo ( 252965 ) on Saturday December 25, 2004 @06:57PM (#11182524) Homepage
        Or another possibility: what if it turns out that an impact will be on an industrialised country "Gog", sufficiently far from a political/economic rival "Magog" to offer no real threat to "Magog"? Would Magog dare to offer less than 100% of what it can offer to preventing the disaster, either publically or otherwise?

        To get a clue as to the answers, look at the recent devastating earthquakes in Iran - even though Iran was on his "Axis of Evil", Bush was offering aid almost immediately. Sure, besides the humanitarian side, there is also political capital to be made on such a gesture, but that's by the by. I have absolutely no doubt that if this, or any other asteroid, is going to hit us then every capable nation will be working 100% to prevent the impact, no matter where it might be.

        • Re:Let's say that the thing will hit (Score:3, Interesting)

          by Anonymous Coward
          You might find this interesting then, in regard to the humanitarian aid offered to Iran in the wake of the Bam earthquake: "President Mohammed Khatami has said only $17m of assistance had been received from abroad, out of the $1bn initially promised." ( full article [bbc.co.uk]). 30,000 dead, 70,000 left homeless and only 1.7% of the promised humanitarian aid delivered a year later - this thing had better not be on a collision course if that is anything to go by!

          BTW, I can only assume that whoever moderated the par

    • The way I see it, we've got about 24 years to party before the world ends. Have another glögg!

      "A close encounter, with 1% or greater chance of a collision capable of causing regional devastation."
      Hardly world-ending.

      Seriously, if it hits 5 or greater on the scale, then we'll have reason to really worry. In the meantime, it's sufficient to just watch and see what happens. As phreakuencies pointed out, right now there's a 97.8% chance of absolutely nothing happening.

      It can only go to 5 or 9.

    • Comment removed (Score:5, Insightful)

      by account_deleted ( 4530225 ) on Saturday December 25, 2004 @07:01PM (#11182534)
      Comment removed based on user account deletion

      • Re:Party like it's 2099 (Score:5, Informative)

        by Scarblac ( 122480 ) <slashdot@gerlich.nl> on Sunday December 26, 2004 @05:20AM (#11184149) Homepage

        Of course the statistics change - more measurements are being done, so the error margin on the estimate goes down. There is a band of possibilities, a bunch of possible trajectories, and more measurements make that band smaller.

        Currently Earth is still within that band, and Earth's diameter is about 1/45th of the width of the band, so that's the probability of a hit.

        Since more measurements are being done, we'll see this for a few more days - either the band is smaller and Earth is still within it, which raises the probability, or the band is smaller and Earth isn't in it anymore, and the probability drops to 0.

        Saying this is "fiddling of statistics" is an insult to the mathematicians involved.

        (Story above is simplified, by making it 2D instead of 3D, and by ignoring the fact that it's probably not some fixed area but the probabilities of the thing going outside the area are smaller and it's some weighted average, and I don't really know anything about the maths, I just think it's obvious that the probability would change quickly).

  • Which Comes First (Score:3, Funny)

    by husker_man ( 473297 ) on Saturday December 25, 2004 @05:34PM (#11182197)
    Which will come first, 2004 MN4 asteroid, or
    Duke Nukem Forever?
    • Daily computations made on 25 Dec raised it's chances up to 1/45.
      And assuming it does destroy modern civilization, then we only have 25 years left to get through to the people who still don't understand the difference between its and it's. Time for a crash program!

  • Whew (Score:3, Funny)

    by Anonymous Coward on Saturday December 25, 2004 @05:34PM (#11182199)
    At first I thought it says " it has a 97.8% probability of hitting earth"

    Good thing i read it over again.

  • Impact calculator (Score:5, Informative)

    by Nine Tenths of The W ( 829559 ) on Saturday December 25, 2004 @05:36PM (#11182210)
    Just to reassure you
    http://janus.astro.umd.edu/astro/impact/ [umd.edu]
    The impact comes out as somewhere between 450MT and 1.6GT, depending on speed and composition

    • Re:Impact calculator (Score:3, Informative)

      by Anonymous Coward
      For comparison, the Tunguska [wikipedia.org] blast, which felled trees over 2150 square kilometers, was 10-15 MT. So if this rock hits us, it will be about 43-160 times more powerful. This won't end life as we know it, but it'll be really bad for the area it hits. Let's hope it doesn't land in the ocean.
    • The largest nuclear bomb ever detonated had a power of 50 to 57 MT, and the light from the explosion, despite a cloudy sky, was visible from over 1,200 miles away, and I think scientists measured its shockwave circumnavigate the earth three times.

      450MT and 1.6GT is a LOT more than even that. If it hits, it won't wipe out humanity, but I think it might have a very strong effect on the weather and water if it hits water, and it might collapse or destroy a few nation-states if it hits land.
  • Come on, bring on the jokes about Nuke Dukem Forever. :)

  • 10 Bucks on Florida (Score:4, Funny)

    by GeekDork ( 194851 ) on Saturday December 25, 2004 @05:41PM (#11182234)

    'nuff said

    • Ohio (Score:3, Funny)

      by katharsis83 ( 581371 )
      Considering the 2004 US Presidential Elections, it'd be pretty damn ironic if it hit Ohio.

      Wonder how the Christian fundamentalists in America would spind THAT.
  • Even if - as is likely - 2004 MN4 is not on course for Earth, the probability of impact will increase with each observation that does not exclude it hitting entirely, as the region of possible places it can be shrinks.

    • Re:Something to bear in mind (Score:5, Informative)

      by barawn ( 25691 ) on Saturday December 25, 2004 @05:55PM (#11182296) Homepage
      That's not necessarily true. It depends on the characteristics of the error.

      If the errors are Gaussian, if the nominal trajectory (i.e. "it misses the Earth by X+/-Y km") is accurate, but imprecise (that is, X is correct, but Y is large compared to X) then the probability of impact will decrease as the precision is improved (i.e. as Y decreases) because the "Earth impact" possibility moves farther out on the fringes of the observation, and the area doesn't shrink fast enough to compensate for this.

      Of course, if the errors are flat (all solutions are equally likely - actually, if the PSF falls off slower than the area shrinks) then you're correct. I'm pretty sure that they're Gaussian, or approximately Gaussian, though. So the only way the probability could be increasing is if the nominal trajectory's impact parameter is decreasing - that is, closer impact.

  • We're doomed! (Score:4, Funny)

    by Quixote ( 154172 ) on Saturday December 25, 2004 @05:45PM (#11182253) Homepage Journal
    In 29 hours, the impact probability has gone from 0.015873 to 0.022.

    If this trend continues, expect an impact in another 4629 hours, or about 193 days!

    It's going to be one hot summer...
    ;-)

  • Seriously, you might as well relax. (Score:4, Insightful)

    by Faust7 ( 314817 ) on Saturday December 25, 2004 @05:45PM (#11182256) Homepage
    You know in all those movies where some guy, sometimes just an amateur scientist, sees something in his telescope/seismograph/thermometer/disease-modeling -software that all the high-up professionals miss, and rushes in to warn the government?

    That doesn't happen.

    So kick back and relax in the knowledge that, even if a global catastrophe is imminent, there's fuck-all you can do about it, except make yourself a quick drink.

    • Re: Seriously, you might as well relax. (Score:5, Funny)

      by Black Parrot ( 19622 ) on Saturday December 25, 2004 @05:49PM (#11182267)


      > You know in all those movies where some guy, sometimes just an amateur scientist, sees something in his telescope/seismograph/thermometer/disease-modeling -software that all the high-up professionals miss, and rushes in to warn the government?

      > That doesn't happen.

      You're with the agency that makes those guys disappear, aren't you.

    • I think it would be something that probably would be averted. I mean think: there's 24 years before this happens. So if it becomes known that it will, for certianty, happen, we have over two decades to solve the problem.

      Generally, if we can predict a disaster with enough lead time, the disaster is averted because we work to avert it. This certianly isn't true of everything, but I'd give a pretty good chance that we could come up with something to mitigate the problem of this asteroid in 24 years.

    • Realize this... (Score:4, Insightful)

      by Kjella ( 173770 ) on Saturday December 25, 2004 @06:10PM (#11182347) Homepage
      ...we're looking at very little of the sky *at one time*. I don't think it takes much amateur equipment to spot something which would be missed by "normal" study, which usually involved spendning forever looking at one tiny fixed part of the sky to gather enough light/EM to make a clearer picture than the last one (i.e. mapping space).

      Kjella
  • "It's coming right for us!" >crash

    It's 20+ years out... C'mon... When we get within a year or two and it still has a 97.8% chance, I'll worry. But we've got to prove we can't blow the world up ourself first!
  • FYI: It is a 400 meter astriod. http://www.universetoday.com/am/publish/asteroid_2 004_mn4.html
  • 1) build spaceship
    2) build mars habitat (hurry not much time left)
    3) ...
    4) profit!

    My uncle is really pissed. He made some thought experiment (32 questions) for "if the world was no longer habitable" and the date he picked was just a few years off.
    http://32q.com/ [32q.com]

    If only he had picked the right date, he probably could've started his own cult or something. Then he could use their power to build a space ark and profit, as noted by the guidelines above. Well, back to the drawing board.

  • Science Desk Home for the Holidays (Score:4, Interesting)

    by DumbSwede ( 521261 ) <slashdotbin@hotmail.com> on Saturday December 25, 2004 @05:49PM (#11182268) Homepage Journal
    I have to confess I have been googling on this matter the last 24 hours and am surprised by how many news sites picked up on the 1/233 1/300 chance when at 2 on the Torino scale, but a full day later, no major news sites are mentioning the move to a 4 (currently a 1/45 chance).

    I don't see a conspiracy here, and do think we will be missed, but given how much they hyped previous possible events with less statistical support it is curious they aren't doing follow ups. Could just be that it's Christmas, and things in the science departments are on autopilot.

    If this thing stays greater than 1/100 by Monday, expect the papers and television to start picking up on it again. There was a close encounter today with 2004-vw14 (something like 5 lunar orbit distance), and the kooks where on the net prophesizing doom (even though it wasn't all that big a rock). It may take some years to really get a bead on where this thing is going, likely going up and down in probability.

    Expect no fewer than a dozen Death-Cults if it stays in double-digit probabilities. Do the Darwin Awards cover Death-Cults?

  • Exciting! (Score:5, Insightful)

    by DogDude ( 805747 ) on Saturday December 25, 2004 @05:49PM (#11182269)
    Am I just sick, or do other people find the possibility of this thing hitting to be pretty damn exciting? The chaos, the devestation, the panic, the collapse of all social systems... jeez, that would honestly be one of the coolest (And last) things to ever happen in most of our lives. The timeframe is nice too... many of us that are currently in our late 20's, early 30's will be wiped out before things start going really downhill for us (physically), but we'll have enough time to get a decent bit of fun stuff done too. Bring it on!

  • Common mistake in press coverage (Score:5, Insightful)

    by AxelBoldt ( 1490 ) on Saturday December 25, 2004 @05:50PM (#11182270) Homepage
    Many press reports essentially say "the chances of impact is relatively high with 1 in 45, but don't worry since it is almost certain that future observations will exclude the possibility of impact." Even the original NASA report contained a sentence like that.

    It's important to note that if the chances of impact are 1 in 45, then the chances that future observations will exclude the possibility impact are 44 in 45.

    The two events "asteroid hits us" and "we can never exclude the possibility of it hitting us" are equivalent: the first happens if and only if the second happens. Therefore the two events have the same probability.

    So the "don't worry" part of the above sentence is pointless: the second half sentence is a mere reformulation of the first; there is no reassuring "extremely high" probability that future observations will correct the number downward.

    • I'm not so sure that I follow you. The impact happening or man being able to predict it are two independent concepts. We can predict that it will happen and still be wrong; likewise, we can predict that it won't happen and be dead wrong (literally). The impact probability is cumulative, but every observation introduces a certain amount of error, some of which can be compensated for (known quantities like the CCD resolution of the telescope that took the measurement), while others can't (human error, poor ca
      • Well, I'm assuming of course that the prediction mechanism is adequate, meaning that NASA's impact probability predictions get better over time, and right before the impact date they will be either (very close to) 0% or (very close to) 100%.

        The latter will happen if and only if the asteroid actually does hit us. So the events "asteroid hits us" and "NASA eventually predicts that it will hit us" are (very close to) equivalent; they are not independent concepts as you claim. The two events have therefore (v

      • Well, seems you don't get the problem.

        Simple map of the Earth moon Sysstem:
        1 _ _ _ 10 _ _ _ 20 _ _ _ 30 _ _ _ 40 _ _ _
        E ... m
        Simple map of the path of the asteroid:
        / / / ... ... / / /
        That should be 42 stripes but the junk char filter ....

        As you see, the first stripe hits earth, the other 41 don't hit. Well, moon is in fact at opposite position when the asteroid comes in, but it was difficult to "draw" that. So, remember moon wont be hit.

        Further observations of the asteroid will give us more data to determine wether the asteroid will travel stripe number 1 or 2, or wether it will travel stripe number 20 or 30 or whatever.

        If we figure the asteroid is traveling NOT stripe 1 we are 100% certain that it will miss us.

        If we figure the asteroid will not travel stripes 31 to 42, the likelyhood of an impact increased to 1:30.

        Both calculations are "100%" certain. OTOH, your parent was right. The likelyhood that the chance of getting hit decreases is high. You have 42 draws ... and in 41 draws you have the chance that stripe number 1 -- the stripe which hits earth -- is removed from the set or possible pathes. Because more accurate measurement shows that the asteroid wont go that path/stripe.

        angel'o'sphere

  • Terminology (Score:2, Informative)

    by Anonymous Coward
    Let's get the terminology straight here.

    Chance is measured in percent. Probability is measured as a decimal or fraction between 0 and 1, with 1 being 100% certainty. Odds are measured as a ratio such as 1,000,000 to 1.
  • I, for one, will give 100,000-to-1 odds that the favorite, earth, will survive 2004 MN4. Paypal accepted.

  • Not too big a deal, I think (Score:5, Insightful)

    by philovivero ( 321158 ) on Saturday December 25, 2004 @05:56PM (#11182299) Homepage Journal
    From the last post about this, I went and read up on the whole thing. I went to the beautiful CGI script where you input asteroid size and velocity and all that, and assumed I was 100km from the impact.

    I had to up the asteroid size to 1300 metres and a velocity of 14kps of dense rock colliding with porous rock before I could interpret the results as something that would suck for me (2nd degree burns on my body from the fireball).

    There would be no major earth effects of such an asteroid hitting Earth, so it said.

    Compare these stats against our current fearsome asteroid.

    In one thread I saw someone refer to this as possibly a human-extinction event. I have a hard time believing that once I actually bother to go check this out. It'd sure suck for everyone within 100km of the impact site but for everyone else, I guess we'd have about the same effects as a major earthquake to deal with.
    • 1300 meters is not that big and they can travel up tp 80kps.

      This one is 2.9 miles wide which is over 6k meters.

      A 1300 meter meteor could easily create a 20 mile wide creater and could cause disasterous tidal waves and tsumias that extend many miles inland.

      The human species would survive but 90% of us live near a body of water.

    • Re:Not too big a deal, I think (Score:5, Insightful)

      by coyote-san ( 38515 ) on Saturday December 25, 2004 @08:36PM (#11182889)
      Maybe you'll "only" get second-degree burns from the fireball, but what about everything else in your vicinity exposed to the same energy?

      Anyway, for large nuclear explosions radiation isn't an immediate concern. If you're close enough to catch much radiation you're already dead from the other effects. What kills you at distance is the overpressure wave and the radiant energy. The former knocks down structures and the second ignites fires that grow into firestorms.

      If you think back to those early films of atomic bomb tests, that's why the paint on the house smolders (radiant energy) before being blown to kindling (overpressure wave). Terminator 2 showed the same sequence.

      You might think you're safe from 2nd degree burns if you hang out side during the initial flash, but that won't do you much good if the house is blown down around you.

      P.S., before somebody mentions it a nuke's nuclear reaction has stopped long before the fireball is a foot or so across - the size of the original warhead. Afterwards everything else is a case of extreme thermodynamics, the origin of the energy is irrelevant.

      An impact's fireball is far more spread out, but it ultimately comes down to a very large fireball and local seismic effects.
    • Assuming that the thing hits us, we have LOTS more to worry about than only whether we personally get 2nd degree burns from the core fireball. Even if it hits on land, there will be a fairly wide zone of ejecta debris (hot rock) falling, starting fires, etc. If it hits in the ocean, it will be MUCH worse -- think colossal tsunami, as in several hundred feet. 1500 megatons is not the end of the world, but it is nothing to sneeze at.

      If we are lucky enough to have it hit in a very sparsely populated land m
  • It looks like that server just got hit by a meteorite. Oops.
  • Now I know this might be a world killer, etc, but someone should be able to tell me with the trajectory it is on, which way the earth would be facing should it hit....

    I'm just curious what will be cratered, what will be melted, what will be evaporated, and what will just die.

  • it actually can be a good thing (Score:5, Insightful)

    by BigGerman ( 541312 ) on Saturday December 25, 2004 @06:07PM (#11182341)
    you know.

    Imagine how much technology boost all the related stuff will receive. If the Moon shot (the pure publicity stunt) generated so much progress, imagine this.

    By the time we will know it is going to miss by 500km, we will already have cheap reliable interplanet travel and will be able to melt/mine/whatever the asteroids. Cool.

  • Maybe I'm a sick puppy.., (Score:4, Interesting)

    by TLLOTS ( 827806 ) on Saturday December 25, 2004 @06:15PM (#11182360)
    ...but I sort of hope it is found to have a much, much higher likelyhood of hitting earth, so much so that's it's almost certain to occur.

    Why? Simply because it would post such a great challenge for humankind. It could well bring much greater cooperation between countries, cooperation of a level presently unheard of.

    Certainly, I'm not hoping it actually strikes earth, merely that people work together in order to stop it.

    Just be glad that Bush won't be the president at the time. If it did hit, in US soil no less, then he'd start pouring billions per month into NASA for the development of spacecraft to fight the alien 'terrorists' who threw that asteroid at America.
  • First thing Monday morning, talk to bank about refinancing house with a 25-year balloon mortgage.
  • Crivens! At least we now know why to welcome our new absinth overlord that day.
  • Look, the chances are now 1 in 2!!!

    http://neo.jpl.nasa.gov/cgi-bin/ip?0.5e-0 [nasa.gov]

    Actually, it's not. The URL just lets you plug in any scientific notation number. Hope I didn't alarm you too much. =)

  • The torrino scale creates unneeded histeric people (Score:3, Insightful)

    by Psychic Burrito ( 611532 ) on Saturday December 25, 2004 @06:21PM (#11182391)
    You know what? I think we need sometime else besides the Torrino scale.

    With all those asteroids, it's always the same game: high probability at the start, it goes up or down and after 2 weeks, we've got some numbers that really mean something, but the problem is that during this time, people start freaking out because they would like to hold to some true numbers, not just "probabilities that are bound to change".

    So, what we need to communicate with even more weight than those torrino scale numbers is a "measurement progress percentage" and tell everybody "if it's not 100%, don't worry yet". That way, with the always updated percentage number, the masses can reliably hold to something, and know that "progress below 100% means that what we know is not reliable".

    Actually, for the current incident, we don't have this number, so I really won't wonder if some people will be freaking out over the next few days.

    Astronomers: full exposure it the name of the game! Tell us how long it will take to measure the path, and where you are currently standing!

    Thank you.
    • or, we can just establish a color-coded threat-level scale. Simple, powerful, well understood by the general public ;-)
    • That's what the Torino scale measures. Low numbers such as the current asteroid has are nothing to worry about. And 100 % of what? We have no idea what the final observational accuracy will be, partially because we don't even know what technology will be observing it 25 years hence. Additional numbers will make things more confusing, not less.

    • Re:The torrino scale creates unneeded histeric peo (Score:4, Interesting)

      by VertigoAce ( 257771 ) on Saturday December 25, 2004 @08:00PM (#11182759)
      There are numbers besides the Torino scale. The press doesn't use them because they're not as easy to explain. A value of 4 on the Torino scale explicitly means that the public should not be at all concerned or even really aware of the possible impact. It is meant to attract the attention of other astronomers so that more measurements can be done.

      As far as a measure of progress, here's a simple one. At 100% progress the probability of impact is either 100% or 0%. Intermediate progress is the width of the window in which the impact might occur. If this window narrows to such a point that it does not include the earth, you get a 0% probability. If the earth is bigger than the entire window, you get a 100% probability. Anything else means there is more work to be done. The rate at which the window narrows will depend on the orbit of the asteroid, but that would give you a rough idea of when you'd be 100% sure.

      If you are really curious, the locations and time of every observation that contributes to this is available online [unipi.it]. It's interesting to note that more observations were done today than any other day. This is a direct result of the object being identified as an object of interest on the Torino scale.
  • Reasoning about probabilities is pretty tricky stuff and even reputable physicists often get it completely wrong. Does anybody have more details (maybe a pointer to a publication) about how they arrived at these estimates and what assumptions went into it?

  • "Earth Impact Effects Program" Calculations (Score:3, Informative)

    by CharonX ( 522492 ) on Saturday December 25, 2004 @06:58PM (#11182528) Journal
    Here some calculations I made via the Earth Impact Effects Program [arizona.edu].
    My Parameters: Diameter 390m, Density 3000kg/m^3, Impact Velocity 11 km/s, Angle 45 degrees, Distance from Impact 25 km (sounds acceptably close but not "hey, it hit me on the head" close - if you are closer than that... though luck.)
    If it hits Rock:
    Final Crater Diameter: 4.87 km = 3.02 miles
    The major seismic shaking will arrive at approximately 5 seconds. Richter Scale Magnitude: 6.6
    But watch for the air blast... Max wind velocity: 186 m/s = 416 mph - Multistory wall-bearing buildings will collapse.

    If you are at least 100 km away, you will still feel the earth shake and hear the air blast, but little damage will be done.
    To sum it up, sorry, nope, humanity won't get extinct if this one hits us, and you won't be too affected unless you are rather close to it (100km) or if it hits water (Tsunami anyone) and you live nearby on the coast.
  • "What's everyone so worked up about? So there's a comet, big deal. It'll burn up in our atmosphere and what's ever left will be no bigger than a Chihuahua's head." - Homer Simpson, 2F11, Bart's Comet

  • Important Footnote on the Site (Score:3, Interesting)

    by Master of Transhuman ( 597628 ) on Sunday December 26, 2004 @12:10AM (#11183551) Homepage

    "Impact Probability
    The probability that the tabulated impact will occur. The probability computation is complex and depends on a number of assumptions that are difficult to verify. For these reasons the stated probability can easily be inaccurate by a factor of a few, and occasionally by a factor of ten or more."

    What they don't say is whether the inaccuracy means more or less risk - or both. I assume on either side.

  • actually, it has a 98.7 impact probablility (Score:3, Funny)

    by heby ( 256691 ) on Sunday December 26, 2004 @08:27AM (#11184497) Homepage
    check it out here. [nasa.gov]

    that must be the lamest cgi script i've seen in my life...

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