Become a fan of Slashdot on Facebook

 



Forgot your password?
typodupeerror
×
Space Science

Earth's Asteroid Risk Downgraded 231

xanthines-R-yummy writes "Relax, everyone - the risk of a gigantic asteroid colliding with Earth just got smaller! Nature reports: "A new survey revises down the likelihood of a massive asteroid hitting the Earth by 20-30%. We're only due to collide with rocks larger than one kilometre across roughly once every 600,000 years, it concludes." Whew! What a relief!"
This discussion has been archived. No new comments can be posted.

Earth's Asteroid Risk Downgraded

Comments Filter:
  • I feel so safe (Score:4, Insightful)

    by Atragon ( 711454 ) on Saturday November 15, 2003 @05:08PM (#7483039)
    Wow, we're only slated to be hit by a rock bigger than 1km wide every 600,000 years...

    Man, I guess I won't have to worry about any rocks smaller than 1km big, it's not like they'll do any real damage.

    • Yeah wasn't that last one that Big the one that wiped out the dinosaurs a few million years ago? That would make us Well overdue! That is not good news :)
    • Thank God! Now I can get rid of my aluminum-foil hardhat.
    • acording to my quick calculations, a 0.8km rock flying at 10km/s would have about 3600megatons worth of kinetic energy (presuming that it was about the density of water -- ymmv).

      Given that it would have about a 2/3 probability of hitting water, I'm exepecting some seriously impressed surfers that day.

    • System effects (Score:5, Interesting)

      by Beryllium Sphere(tm) ( 193358 ) on Saturday November 15, 2003 @06:28PM (#7483419) Journal
      You can calculate the energy release, overpressure radius, and so on. You can estimate the casualties and property damage from a half-kilometer disaster.

      My nightmare, though, is having the next Tunguska-sized event happen during the next Cuba-like nuclear crisis.

      It only takes a small rock to do a good short-term simulation of a nuclear weapon going off. If that happened at the wrong place and wrong time, it could trigger indescribable horror.
      • Given how carefully governments watch for missile launches, I doubt that would really be an issue. People might assume that the detonation was nuclear, but in the absence of detected launches, it would probably be attributed to a terrorist attack of unknown origin.
      • an half kilometer asteroid would do much more damage on impact than every nuclear war he could provoke. People messure the energy of such imapct with Gigatons TNT... and mostly hundreds of them...
      • Just don't live near any monuments like the Eiffel Tower, The White House, Golden Gate Bridge etc..

        On the movies they are the things that get hit first!!!
      • THAT'S your nightmare? Your nightmare system is way out of wack. The likelihood of this happening is.... basically 0. We'd have to have another nuclear missile standoff, an asteroid hit in exactly the right place to look like a missle hitting our/their country... seem a little unlikely?

        Plus our satellites will be watching their country... no launch signature means we'd know it wasn't a missile. So the thing would have to come down over the other country at just the wrong time... preposterous.
    • by swordboy ( 472941 ) on Saturday November 15, 2003 @07:25PM (#7483673) Journal
      If you haven't seen the End of the World [tiscali.nl], then have a look at what you are missing.
    • The sad thing is that I only learned of the possible threat through a story on Slashdot saying "don't worry about it". So when the big one comes, I won't know about it anyway. Now when is Friends on next... (j/k!!)
    • No silly. Version 6.6.7 of the Armegeddon ebuild had a compile error for the Mips platform, so they masked it bumping everyone down to 6.6.6.

      Don't you guys read the portage changelog?

  • More importantly... (Score:3, Interesting)

    by ohad_l ( 683421 ) <lutzky@g3.14159mail.com minus pi> on Saturday November 15, 2003 @05:10PM (#7483044) Homepage
    How likely are we to be able to nuke 'em once we see them? How likely are we to see those anyway? We've had several near-misses that we only detected after the asteroid passed us...
    • by fname ( 199759 ) on Saturday November 15, 2003 @05:24PM (#7483128) Journal
      Depends on the advance warning. With 30-40 years notice, we'd probably have time to send out a scout team to characterize the asteroid. Then, we could send a follow on team with the proper explosives and nukes. Hit it soon enough (at least a couple years before collision), and we could deflect it.

      Some folks think that painting it is a better solution. You see, if you paint part of it white, it will deflect the asteroid by about 1 earth-radius 20 years ahead of time. (Less than the margin of error in our guess, most likely. Might knock it into us.) And, to paint a 100-meter or 1-kilometer rock takes A LOT of paint.

      Anyways, the short of it is, if it's an asteroid, we can probably have 100 years notice if it's big enough (not today, but our detection ability is improving). If it's a comet, we might only have a few months notice. Then we'd be in trouble.
      • There's the catch. *With* 30-40 years notice. We recently noticed a large asteroid only after it passed between us and the moon. If we are going to protect ourselves (if there's a good chance at 600,000 years, there's still a chance now) we had better get our act together. What would that require?

        Not much. An array of 100 or so 1-meter telescopes spread throughout the northern and southern hemispheres would do the trick. Sure, every patch of sky wouldn't be observed each night, but with the right sp

        • Plotting their trajectories is something else

          Plotting the trajectory of an object is easy once you know it's there. Especially if you have 100 extra telescopes available.

          TTFN
      • by Dark Lord Seth ( 584963 ) on Saturday November 15, 2003 @06:11PM (#7483340) Journal
        Some folks think that painting it is a better solution. You see, if you paint part of it white, it will deflect the asteroid by about 1 earth-radius 20 years ahead of time. (Less than the margin of error in our guess, most likely. Might knock it into us.) And, to paint a 100-meter or 1-kilometer rock takes A LOT of paint.

        That, and hiring a small army of painters to actually paint the damn thing would cost a fortune! They charge a fortune for coming over here even if they are from the same town, can you imagine what they would charge for going to an object somewhere between Mars and Jupiter?

      • What if we paint it with a nuclear paint bomb? That way we get the best of both worlds.
      • by RabidStoat ( 689404 ) on Saturday November 15, 2003 @07:26PM (#7483679)
        Depends on the advance warning. With 30-40 years notice, we'd probably have time to send out a scout team to characterize the asteroid. Then, we could send a follow on team with the proper explosives and nukes.

        Couldn't we send in a team of negotiators to try reasoning with it ? Maybe offer it a bribe to hit the next planet along ? If all else fails we could try mocking it.

      • Depends on the advance warning. With 30-40 years notice


        You'll never have 30-40 years' notice. You won't know for sure if it's even going to hit you until more like the 2yrs timeframe, and even then, there's a chance it will miss. There is just no instrument on earth with enough accuracy to determine 90%+ that an asteriod is on a collision-course given that kind of time frame.
      • How does the paint work? I didn't know, so I googled and found this PDF [usra.edu] about the Yarkovsky effect.

        Google's HTML transcript [google.com.au]

  • Thank goodness - I was worried.
  • Hmm (Score:5, Funny)

    by Bigthecat ( 678093 ) on Saturday November 15, 2003 @05:11PM (#7483049)
    Will this finally put an end to all those damn asteroid-hitting-the-Earth movies?

    Please?
  • by Dimwit ( 36756 ) * on Saturday November 15, 2003 @05:12PM (#7483051)
    I mean, there hasn't been a rock that large hitting us in, like, 599,000 years...

    Aw FUCK!
  • We're only due to collide with rocks larger than one kilometre across roughly once every 600,000 years, it concludes

    Ah, yes grasshopper...but what are our chances of colliding with copies of bad asteroid movies in the video rental store?

  • Now, what can we do about Yellowstone [usgs.gov]?
    • From the same website. [usgs.gov]

      So what's the big deal?

      There may be none. This region has active hydrothermal features, and possibly some uplift. It's possible that the area could host future hydrothermal explosions, but so could other areas beneath the lake and other areas within the Park.

      Do any of the features beneath the lake relate to possible volcanic eruptions?

      It is very unlikely. All active features are related to faults and hot water (hydrothermal) vents. Identified craters were formed by
  • Bam! We get hit tomorrow...
    • Yeah, you'd better make a landing area in the backyard, and that should be with all lights even including flashy green ones and those which change color.

      p.s. Do not forget about hot-dog stand, who knows it might even be an attraction and youmight even make profit

      Simple steps of this bussines plan:
      1. Asteroid lands in your backyard
      2. hot-dog stand has being prepared
      3. PROFIT
  • You're not going to die from a killer-asteroid fall.

    You can now safely return to previous activity.
  • by NightWulf ( 672561 ) on Saturday November 15, 2003 @05:16PM (#7483078)
    That the dinosaur version of Slashdot released that same story on the Jurassicnet just 48 hours before they left the earth.
  • "There was a lot of error in our previous estimates," says astronomer Alan Harris of the German space agency, DLR. "It's all because near-Earth asteroids are somewhat brighter than we thought".

    lots of errors is a bad thing. what if their estimates are wrong now, and the previous estimates were right. I hope it's not the same people who made the previous calculations. And who exactly did they survey?
  • by Chromodromic ( 668389 ) on Saturday November 15, 2003 @05:19PM (#7483099)
    This must just be an abysmally slow news-for-nerds day or something because, you know, the joke in the post is valid. Did anyone breathe a sigh of genuine relief here? Did anyone go, "Oh, God, well, now I can stop worrying about that!"

    Did anyone see Armageddon and then go home unable to sleep for nights on end?

    I just find it hard to believe that in the vast informational space of the Internet, this is a story that collided with the front page of Slashdot.

    The analysis doesn't change the chance of an asteroid hitting the Earth, points out astronomer Iwan Williams of Queen Mary University of London, UK. "But assuming that there are fewer large asteroids, the damage will be less," he says.

    When news editors say, "Damn it, just print something!", this is what we get.

    • by Anonymous Coward
      i saw armageddon, then wished i hadn't wasted money on a stupid, excessively emotionally charged fake piece of crap movie with a dumb love story tied in. yeah sure. go chase one of your employees through the ramparts of a fucking oil thingy in the ocean with a shotgun (was it?). oooo yay. if you actually thought that was anything remotely sane you're a fucking moron. your comment makes me incapable of sleeping at night, you fucking jackass piece of shit cocksucker fucking dualksjdf;oaihg80h24b80h
    • What other page would it make? Slashdot, like any news source, is just trying to find content. I can think of more trivial articles than this in the recent past.
    • Actually, I can't think of anything more terrifying than the extinction of the human species. What's even scarier is that unlike most things that threaten a person's existence (beyond just getting too old), there's absolutely nothing you, nor anyone else can do to prevent this.

      Do I lose sleep over it? Not really. But to me it's like contributing to a pension - you may never see it, it won't happen for decades, but you do it anyway. Because when the time comes it will be the single most important thing in y
    • Did anyone see Armageddon and then go home unable to sleep for nights on end?

      Yes. Although it didn't have anything to do with a fear of asteroid strikes.

    • Basically, I watch 'Earth getting blown up' movies for one reason, and one reason only. I love seeing Earth explode with all the nifty special effects Hollywood can muster. Nothing much hit the earth in Armageddon, and that was a big dissappointment.

      In the same way that the destruction wreaked by whatever bad guy really makes the Final Fantasy series games, and many an anime flick ( most of which feature the end of the world as a minor plot point ) I enjoy watching the Earth blow up in major Hollywood fi

  • by mattyp ( 720004 ) on Saturday November 15, 2003 @05:23PM (#7483120)
    It makes a big difference. If it's a Poisson Process, no matter how long we wait, every day our probability of being struck remains the same. If not, every day that we don't get struck, increases our probability for getting struck the next day.
  • down 20-30%...? (Score:3, Interesting)

    by Devil's BSD ( 562630 ) on Saturday November 15, 2003 @05:25PM (#7483131) Homepage
    if we're going to be hit by a massive asteroid approximately every 600,000 years, doesn't that kind of make the probability 100%?
    • Re:down 20-30%...? (Score:3, Informative)

      by EulerX07 ( 314098 )
      Not really. Even if statistically one should hit every 600 000 years, it is statistically possible to go 2 million years without any impact.

      Flip a coin. You've got 50% chance of getting heads or tails. But it is possible to get heads 10 times in a row. The odds of this combination happening is 0.5^10*100 (in percentage = 0.09765% chance of happening).

      An event that has 1/600 000 years chance of happening does not have a 100% chance of happening every 600 000 years.

      Been a while since my stats course and I'
  • LIES! (Score:5, Funny)

    by Lord_Dweomer ( 648696 ) on Saturday November 15, 2003 @05:26PM (#7483134) Homepage
    This is just what they want you to think. They just don't want everybody panicking right up until we do get hit! LIES! ALL LIES!

    (The preceding text is brought to you by the Tin-Foil Society for Public Awareness, have a nice day.)

  • IF we were under a threat ? What would be the strategy ?

    Rockets that use nuclear bombs ? Or use retrorockets to push the asteroid ? Lasers ?

    • by Danse ( 1026 ) on Saturday November 15, 2003 @06:06PM (#7483325)

      World leaders would retreat to their shelters deep within the earth where they have been hoarding food, fuel, HDTVs, and Playboy Playmates. They'll start a new civilization consisting of moderately attractive people that don't know how to do anything except lie, cheat, steal, and make a fantastic raspberry smoothie.

  • ... that we now get hit by an asteroid.
  • Duh (Score:5, Insightful)

    by benk ( 93688 ) on Saturday November 15, 2003 @05:41PM (#7483201)
    > "Relax, everyone - the risk of a gigantic asteroid colliding with Earth just got smaller!"

    Surely the risk hasn't changed, just our estimate of it...
    • by Evil Pete ( 73279 ) on Saturday November 15, 2003 @06:45PM (#7483498) Homepage

      The article points out that rather than there being 20-30% fewer rocks out there which could hit us, they are 20-30% smaller. So the chances of being hit are not less, just the chances of of it being over the magic size 1 kilometre (claimed to be the size required to knockout civilisation or whatever).

      • You miss The point, neither the risk nor the chance of it being a certain size have changed. If you look at the empire state building and say it's 1300' tall, you then measure it with a tape measure, you don't change it's height
        • As I recall, the article states that there are a certain number of kilometre sized objects which are known. New more accurate measurements now show that the objects are 20-30% smaller than originally thought. So there are fewer 1 km objects (down from about 1300 to about 1000 ... though I'd have to recheck the article), but none of the original objects have gone away and these objects are Apollo objects ... the ones most likely to hit the Earth.

    • Surely the risk hasn't changed, just our estimate of it...

      Now think about that a bit...our estimate of it is the only thing we are talking about when we talk about such predictions. If we had all the information there was to have, we wouldn't talk in terms of risk, we could just say exactly when one would hit. (ok, i suppose quantum theory introduces a certain level of true uncertainty, but still....)

      Another of saying it is, if the weatherman was smart enough, there is never really a 60% chance of rain
      • Another of saying it is, if the weatherman was smart enough, there is never really a 60% chance of rain tomorrow ....its either 0% or 100%

        Reminds me of an old joke about blondes and statistics.
        When asked from a blonde what are the changes of seeing a dinosaurus walking on the street tomorrow? Close to zero? zero? nope, 50/50. Either I see it or I don't.
  • I wouldn't worry (Score:3, Interesting)

    by earthforce_1 ( 454968 ) <earthforce_1@yaho[ ]om ['o.c' in gap]> on Saturday November 15, 2003 @05:41PM (#7483204) Journal

    We have plenty of more probable ways to destroy civilization. Assuming we do absolutely nothing about the problem for another 1000 years, the change of getting clobbered by "the big one" is still miniscule, and the odds are still much less that we won't detect it in enough time to do something. There have been a few near misses that were not detected until the last moment, but many others were found with decades of warning - enough time to devise a mission from scratch to push the sucker into a slightly different trajectory.

    And by that time I predict we will either be i) extinct, ii) living in a second stone age, or iii) have unimaginable technology such as planet wide deflector shields or some super weapon that could take care of the problem in the blink of an eye.

    • Re:I wouldn't worry (Score:3, Interesting)

      by Saeger ( 456549 )
      or iii) have unimaginable technology such as planet wide deflector shields

      With "unimaginable technology" why would you assume the majority of life will still be living in fragile bio-based bodies at the bottom of gravity wells with tons of wasted molecular building material beneath our feet?

      I say we rip the Earth apart [aeiveos.com] to put it to better use - sentimental value be damned! :)

      --

    • For some reason your post reminded me of this:

      Smithers: Oh Mr. Burns, we'll thaw you out the second they discover the cure for... seventeen stab wounds in the back. How are we doing boys?

      Professor Frink: Well, we're up to fifteen!

      It also reminds me of the mentality a lot of people still have re: the environment. Destroy it now, because by the time it really matters we'll either be dead from something else, or we'll have such good technology we can fix the damage.
  • If these guys are so smart, why were all those recent close calls such a surprise? Someone is playing with numbers here so I wouldn't get all cozy about being prefectly safe from THE BIG ROCK.

    Then again, Mr Bush will probably cause WW III so what's THE BIG ROCK going to do but kill a dead planet. ;-)

    Dr Smith: Doomed, we're all doomed.

    LoB
  • Just relax... (Score:2, Interesting)

    Yeah, take it easy. Two major asteroids passed within 200,000 miles of us (less than the distance to the moon) in the last year or so... http://science.slashdot.org/article.pl?sid=02/01/0 7/138256&mode=thread&tid=160 http://science.slashdot.org/article.pl?sid=02/06/2 0/1916206&mode=thread&tid=160 Fortunately, we didn't know about them until after they had passed...
  • bet it's gonna be a whole lot less time until the impact of another "asteroid impact with earth, starring bruce willis" movie...

  • Great. I had already decided to blow off doing my homework and go out instead tonight, since I figured there was at least a decent chance that the world would be obliterated by an asteroid any day now anyway. There goes my plans for tonight...

  • As usual, my latest investment is now proven to be a total lost cause.

    I had just finished completion of my under ground bunker located 100km beneath the surface with lead walls and a built-in optical-network uplinked to a well fortified satelite dish array (so I can get online, watch some Japanese hentai and shop at eBay till the end of the world)
    And am waiting for my shipment of rations to arrive (FedEx said they'd be here Monday, I was too cheap for the express overnight/weekends)

    So hey Mr. Scientist, F
    • haha, I wonder if in 100 years, we'd have the technology to build something 62 miles under the surface of the earth, in the outer mantle. I haven't heard of any alloys made by man that could endure 10 minutes under those conditions. You might want to get a long tape measure & do a check, I think your contractors lied and only made it 5 miles deep.
      • I haven't heard of any alloys made by man that could endure 10 minutes under those conditions.

        We'll be able to synthesize cheap diamond in mass very soon; its the hardest substance known, and it melts at the insanely high temp of 3546 degrees C. The Earth's mantle is ~3km deep and is "only" 2200 degrees C at its hottest.

        --

        • you forget diamond BURNS LIKE COAL at temperatures of just over 1500 degrees. as the other replier has pointed out, you're a layer off - the outer mantle goes from 7 miles to about 190 miles (10-300 km), with temperatures of 2520 to 5400 degrees F, more than enough to make diamond burst into flame in the presence of oxygen, and to melt steel.
          • ...and Tungten melts at the very high temperature of 3000 degrees F (1650 C). Let's not forget the pressuem, estimated to be 4.5 GPa at 140 km, about 650,000 PSI. I don't think we'll be going down there anytime soon.
  • What a total crock of steaming bovine fecal matter - we have NO idea how often large asteroids have impacted in the past, there are any number of ways the impact craters can be hidden since most of our planet is under water, and glacials have scrubbed large areas of the land masses. And even if we had a perfect record of our past asteroid hits, that has NO bearing on future encounters. There could be a stream of ten 10-kilometer asteroids bound to hit earth in the next 100 years , put on that trajectory b
  • My viewpoint on this is far from mainstream (for now), but I just wanted to say that it would be extremely unlucky for humankind to be wiped out by an asteroid impact -- of all things [gmu.edu] -- in the next ~30-50 years that matters most in our technological evolution.

    It is far, far more likely that our exponentionally advancing technology [kurzweilai.net] will destroy us before we've had a chance to leave the nest, and transcend [singinst.org] to a safer form (non-bio) minus some of our outmoded evolutionary jungle-brain baggage.

    --

  • by Animaether ( 411575 ) on Saturday November 15, 2003 @06:31PM (#7483434) Journal
    Not to slight the research and the pure theoretical chance calculations and all, but..

    The statistics are only as good as the sampling set.. and suffice to say, we're *not* watching every single asteroid out there - greater than 1km (diameter) or not.
    And any single one asteroid we're not watching has the potential to be that 'killer asteroid'.
    And we already know that we've had 'near misses' only realized until after the asteroid had already passed.

    Which means that for any foreseeable future, the practical chance of us getting hit by an asteroid of size 1km in diameter or larger, tomorrow, is 50%.

    Either we do, or we don't. And we won't know until it either happens, or not.
    That's what the uncertainty of the limited sampling set brings us in practice.

    Which doesn't mean that if it doesn't hit tomorrow, that the chances for it hitting the day after tomorrow is 75%. The chances remain 50%.

    What's more interesting is predicting the chances of a particular asteroid we -are- spotting are of hitting us.
    • Yeah, to hell with history! It's 50%.

      By remarkably similar logic, the chances of Jesus' arrival back on Earth tomorrow is also 50%.

      So don't worry about the asteroid, as chances are that Jesus will arrive before or very soon after it hits. But before the bank closes tonight, you'd better stop by and cleanse yourself of the sin of usury, or you're going to burn in hell forever!

      Oh, and please post here to confirm that you've withdrawn your money from all interest-bearing investments. See you in lin
  • I'm so relieved. I think about this daily. It's much more of a concern to me than going bald prematurely, being impotent, or being intellectually feeble.
  • One Asteroid proof bunker, with 500,000 years provisions, cable TV and internet.

  • by RenHoek ( 101570 ) on Saturday November 15, 2003 @07:10PM (#7483613) Homepage
    After watching 'The elegant universe' [slashdot.org] (<--- torrent links)I can trade in my fear for an continent sized asteroid hitting earth for the more bleeding-edge fear of a new 'Big Bang' occuring. :) No rest for the paranoid.
  • What an impact. Someone hit me before I come up with more bad puns. Rock the hou - ouch.
  • the yellowstone caldera blowing its top....it's already "overdue"...

    see this national geographic article [nationalgeographic.com]

    if this thing blows in our lifetimes, the midwest will essentially become Mordor...I guess for some hardcore LOTRs fans that would be kind o' cool...

    Then again, LOTR trilogy is hella better than any asteroid hitting the planet movie...

  • This is great news! I think I will take that vacation after all.
  • But what about them there solar flares? If we ain't gonna get pummeled from behind by a big hard rock, how does that keep us from gettin blasted in the face by a big ball o gas? ;)
  • Relax, everyone - the risk of a gigantic asteroid colliding with Earth just got smaller!

    Yay! Finally the Department of Homeland Security protects us from something!

UNIX enhancements aren't.

Working...