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Asteroid Flies Under the Radar, Literally

mrn121 writes "Space.com is reporting that a 16-foot wide asteriod has passed the Earth in a phenomenally close call. The Asteroid, named 2004 YD5, passed just below the 22,300 mile range where geostationary satellites sit. What makes the incident most interesting is that the asteriod was not seen until after it passed the Earth, due to the well-known Cosmic Blind Spot caused by the Sun."

77 of 385 comments (clear)

  1. First post by IO+ERROR · · Score: 5, Insightful
    Asteroids this small, if they were to enter the atmosphere, would break up and the pieces would burn up on entry. Little or none of it would reach the ground in any form you could recover it.

    The asteroids that are large enough to do damage can be seen far away enough that the cosmic blind spot is irrelevant. The article mentions a 2.9 mile wide asteroid (which would quickly wipe out all life on the planet if it hit) which scientists have known about for years. It won't come anywhere close.

    At the moment, we have no defense against a planet-killing asteroid, but the European Space Agency is studying the issue, and NASA's Deep Impact project is also working on it.

    --
    How am I supposed to fit a pithy, relevant quote into 120 characters?
    1. Re:First post by Laivincolmo · · Score: 4, Informative

      NASA's Deep Impact is going to impact a comet to study the composition of it. If sucessful the impact will create a crater on the surface. It has little to do with breaking up asteroids.

    2. Re:First post by Anonymous Coward · · Score: 5, Funny

      Not really, the asteroid could be totally illiterate and it would still burn up.

  2. Hmm by Anonymous Coward · · Score: 5, Funny
    Someone wants us dead.

    Sounds like we need to send an exploratory force out towards the sun to find out who the bastards are! Maybe they're on venus or mercury or somethin.

    Oh wait. We don't _have_ an exploratory force. Oh well, guess we'll just have to be sitting ducks.

    Or hope this was just a freak coincidence.

    Sounds like a plot for a new movie...

  3. Well if I'm going to be obliterated by an asteroid by Timesprout · · Score: 3, Interesting

    I'd rather not see it coming.

    --
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  4. true but by poison_reverse · · Score: 2, Interesting

    it could have taken out a satellite by chance

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    1. Re:true but by Tablizer · · Score: 2, Informative

      it could have taken out a satellite by chance

      The chances of something that large hitting a given satellite is probably only a bit more than it hitting you. It is a bit more because it may burn up by the time it reaches the ground. There are 5+ billion people and probably only around 2000 active satellites. Assuming such a rock has about a 50/50 chance of making it to the ground without vaporizing, then it is far more likely to hit a person than a satellite.

      (5,000,000,000 * 0.5 * 0.5) / 2000 = 62,500

      (The second 0.5 is because most sats are bigger than people.)

      Thus a person is about 60,000 more times likely to get hit by a rock that size than a satellite.

      Now small rocks are another story. Those pose a far bigger danger to satellites. We on the surface are protected by our atmosphere against pebble- and baseball-sized space rocks. But satellites are not, and those things rip through them like bullets.

    2. Re:true but by Shanes · · Score: 2, Informative

      As others have pointed out the chances for that hapening are very remote, but anyway, here's an interesting graphic showing the 2004 YD5's position when passing compared to all Low Earth, GPS, and geosynchronous sats. As the page says, it passed 1.88 earth radii from the orbit of GPS satellite BIIA-19.

  5. Everybody PANIC!!! by ChuckleBug · · Score: 3, Funny

    My God, we're doomed! I mean, if an asteroid too small to hit the surface can go undetected, how will we blast it out of the sky with our Planetary Orbital Defense Network?

  6. Material Make Up by LabRat007 · · Score: 2, Interesting

    Does anyone know if an asteroid of this size could make landfall if made of the proper materials. Such as nickle, lead or other make up?

    --
    "Capital punishment makes the state into a murderer. Imprisonment makes the state into a gay dungeon-master"
    1. Re:Material Make Up by StarsAreAlsoFire · · Score: 2, Interesting

      A lot of factors come into play. Is it coming 'straight at us' (will it hit the atmosphere with the combined velocities of the orbiting earth and its own relative motion?). Or is it playing 'catch up' with the Earth, coming up behind us so that the relative velocity is lower?

      Hell yeah, a solid nickle object that size could hit the surface given the right conditions! But with a shallow, grazing entry it would be unlikely to do so. And shallow entries are more likely.

      However a fast, dead straight approach would give the asteroid/meteoroid only tenths of seconds of actual atmospheric contact. Earths orbital velocity around the sun is around 30km per second, and if the object were coming straight at us you can assume that its orbital velocity would be near to that; if it were falling toward the sun it would be higher, if ascending the velocity would be lower. So 60km/second would give the object about 1/2 a second in any 'real' atmosphere in a vertical descent profile. For some object which was solid and metallic there would be a nice new crater - not enough time for heat transfer to create the massive thermal gradients which would make the object shatter.

      If the object were not completely solid the shockwaves created by its own passage through the atmosphere would likely cause it to explode into smaller peices, but even then you could expect a good number of those pieces to blast some pretty serious holes in things.

      I once read, LONG ago in some book meant for 'tweens, that objects smaller than a VW bus tend to burn up. Objects larger stand a good chance getting significant chunks of themselves onto the surface of the planet.

  7. Oops? But does it matter? by agent+dero · · Score: 3, Insightful

    While that does kind of suck that we had no idea of it before it passed "close" by, one has to ask, does it matter if we see it coming or not?

    If an asteroid does head for us, will it matter if we see it coming or not? Or will the grandiose idea presented in "Armageddon" be employed (despite being cool as hell.)

    Personally, i'd rather be blindsided by a sixteen-wheeler, than sit by and see it head towards me for hours/days/weeks.

    --
    Error 407 - No creative sig found
  8. Let's see by Linguica · · Score: 3, Interesting

    The diameter of the earth is about 8,000 miles, so take the globe on your desk (you have one, right?) and imagine an object a little less than 3 diameters away...

    1. Re:Let's see by jericho4.0 · · Score: 2, Informative

      0.000195 of a centimeter.

      --
      "A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
    2. Re:Let's see by Anonymous Coward · · Score: 2, Interesting

      Do you think that, if a meteorite with a diameter of 0.24 mm would hit a 30-cm wide globe at a speed of 0.35 mm/sec, this would destroy most form of life on this planet ?

      Yes.

      This is the exact reduced model representing the 10-km wide meteorite that hit the Yucatan Peninsula 65 million years ago at a speed of about 54000 km/h, creating the 170-km wide Chicxulub crater, and caused the extinction of the dinosaurs.

      Impressive, isn't it ?

  9. This is NOT reassuring ... by i_want_you_to_throw_ · · Score: 4, Interesting

    Four small groups of dedicated astronomers in Arizona and California, totaling fewer than the number of employees at an average fast-food restaurant and using mostly off-the-shelf equipment for their telescopes, have been mapping the heavens and steadily adding to the number of known near-Earth objects. The article from TIME is here

    Something more dedicated to this would make everyone feel better probably

    1. Re:This is NOT reassuring ... by Anonymous Coward · · Score: 3, Informative

      your link is defunct, the correct link is http://www.time.com/time/reports/v21/science/aster oid.html

    2. Re:This is NOT reassuring ... by DocSavage64109 · · Score: 4, Interesting

      Even if they did find something, the government would cover it up so as to avoid a panic. May as well save tax dollars and let the amateurs do it.

    3. Re:This is NOT reassuring ... by Anonymous Coward · · Score: 2, Insightful

      What's the point? Is the skipper going to change course? Are we going to somehow vaporize it?

      Who cares how people feel about it. I can see how tracking near-Earth objects might be interesting from a scientific perspective. However, I don't see the point in using a massive amount of resources in doing so just in an attempt to provide piece-of-mind.

      I am the type of person that, in the case of the annihilation of the human race, believes that ignorance is bliss. If a scientist discovers that we will all face certain death in the next 24 hours, I don't want to know about it. If nuclear war broke out, I'd want to be one of the first to fall.

      I, for one, would much rather just go about my ordinary, self-absorbed life and sleep peacefully at night.

      I ask again, what's the point?

    4. Re:This is NOT reassuring ... by Pantero+Blanco · · Score: 4, Insightful

      If there WAS an asteroid hurtling towards us and we had significant warning, I'm sure we could throw something together. If we don't have that ability today, the information we gather now could be useful in the future if such an event occurs.

    5. Re:This is NOT reassuring ... by iamatlas · · Score: 3, Funny
      If there WAS an asteroid hurtling towards us and we had significant warning, I'm sure we could throw something together.

      Dude, like, I know some people who drill for oil that are sooooo the right people to call in on something like this.

    6. Re:This is NOT reassuring ... by Rei · · Score: 2, Interesting

      Bah, I've got a better page than that: calculate your own custom asteroid impact.

      --
      We're all familiar with the tragedy of being you.
    7. Re:This is NOT reassuring ... by Doc+Ruby · · Score: 3, Insightful

      We have a Greenhouse effect that is threatening us NOW, more slowly than a hurtling asteroid - so we can deal with it - but just as inevitably. Instead of doing something about it, we're denying it and making it worse. What makes you think an asteroid won't be "just a theory" to the people too entrenched in feeding at the status quo trough to raise their snouts?

      --

      --
      make install -not war

    8. Re:This is NOT reassuring ... by Ralph+Wiggam · · Score: 2, Funny


      I think watching the world go all Mad Max would be really interesting. I plan on welding spikes on a dune buggy for no reason.

      -B

    9. Re:This is NOT reassuring ... by HeghmoH · · Score: 3, Insightful

      Newton's law of gravitation is much simpler than the incredibly chaotic system that makes up our climate. Once such an asteroid is discovered and the details published, anybody with a year or two of university-level math and physics will be able to verify its path.

      --
      Mod down posts with a "Free Mac Mini/iPod" sig, they're spam!
    10. Re:This is NOT reassuring ... by EvilTwinSkippy · · Score: 2, Funny
      4:17 GMT, March 8 2007

      Just look surprised.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
  10. 16-foot ASTEROID? by Marxist+Hacker+42 · · Score: 2, Insightful

    Heck, I've seen BOULDERS bigger than that (if you ever visit Central Oregon, the High Desert Museum has one about that size sitting on top of a car- it's pumice obviously). That ain't no asteroid, that's a meteor.

    --
    SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
    1. Re:16-foot ASTEROID? by Anonymous Coward · · Score: 2, Informative

      Pedantic Man to the rescue!

      You meant meteoroid, not meteor. A meteoroid is a solid body, moving in space (not in atmosphere), that is smaller than an asteroid and larger than a speck of dust. It becomes a meteor when it enters a planetary atmosphere (and meteoroids almost invariably burn up on atmospheric entry).

      Pedantic Man, away!

  11. Planet saving == funding drive by EmbeddedJanitor · · Score: 5, Funny
    How people love to play on our fears to get power, money etc.:

    Church: "Give us your money and listen to us or you BURN IN HELL!"

    DOE: "Give us your money etc or YOU'LL RUN OUT OF GAS!"

    NASA: "Give us your money or YOU'LL GET KILLED BY AN ASTEROID!"

    --
    Engineering is the art of compromise.
    1. Re:Planet saving == funding drive by Tablizer · · Score: 4, Funny

      How people love to play on our fears to get power, money etc.:....NASA: "Give us your money or YOU'LL GET KILLED BY AN ASTEROID!"

      The Dinosaurs didn't fund their NASA, and look what happened to them.

    2. Re:Planet saving == funding drive by Otter · · Score: 4, Funny

      Hey, they also pissed off God so much he wrote them out of the Bible! The dinosaurs weren't much for hedging their bets, apparently. They did solve the gas problem, though, although not really to their own advantage.

  12. Asteroid shield instead of missile shield by Elkboy · · Score: 2, Interesting

    Here's something we know will come and that has a destructive potential far greater than anything in our arsenals. It would foster global cooperation since all nations are potential targets, and it wouldn't create an arms race. An asteroid shield seems like a better way to spend all those money that goes into missile shield defense.

  13. Dupe by Anonymous Coward · · Score: 2, Funny
  14. Yay... by Scrab · · Score: 5, Funny

    Stealth Asteroids....

    I'm not worried though.

    I have my teeny triangular space ship, and I'll destroy it before it becomes a problem....

    --
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  15. End of the world website by RagingChipmunk · · Score: 2, Interesting

    End of the world chart in true scientific fashion - a website dedicated to tracking asteroid collision paths - a 'solution' euphamistically means 'striking the earth' http://www.hohmanntransfer.com/crt.htm#news

    --
    The only PT Boat Journal on the web: http://www.PT171.org
  16. RTFA, mrn121!!! by JonLatane · · Score: 2, Informative
    The asteroid was not 16 feet wide.

    According to the article, "the object, now named 2002 EM7, was probably between 40 and 80 meters (130-260 feet) in diameter" and was capable of flattening a whole city.

  17. asteroid, meteor, meteoroid, meteorite by Animaether · · Score: 5, Informative

    Just to correct something...

    Asteroid:
    Any of numerous small celestial bodies that revolve around the sun, with orbits lying chiefly between Mars and Jupiter and characteristic diameters between a few and several hundred kilometers. Also called minor planet, planetoid.
    I.E. still in space and orbiting.

    Meteor:
    A bright trail or streak that appears in the sky when a meteoroid is heated to incandescence by friction with the earth's atmosphere. Also called falling star, meteor burst, shooting star.
    I.E. that which is shooting through the atmosphere, heating it and itself up in the process due to friction.

    Meteoroid:
    A solid body, moving in space, that is smaller than an asteroid and at least as large as a speck of dust.
    I.E. still in space, not necessarily orbiting, smaller than an Asteroid. I think you meant this one.

    Meteorite:
    A stony or metallic mass of matter that has fallen to the earth's surface from outer space.
    I.E. Fallen onto the Earth. It's what you may find if you're either lucky, or very observant.

    So just to conclude.. this is indeed a Meteoroid, as it's not big enough to actually be an Asteroid. But it's more fun to say, and less confusing to the masses - especially the Nintendo owners out there.

    1. Re:asteroid, meteor, meteoroid, meteorite by kinema · · Score: 2, Funny

      Metroid: Species of jellyfish-like alien predators from SR-388.

  18. WARNING! by Spy+der+Mann · · Score: 4, Funny

    Asteroids may be closer than they appear.

  19. What's the burning about? by Elkboy · · Score: 2, Interesting

    Speaking of asteroids... I've heard somewhere that the burning of objects that enter the atmosphere being caused by friction is a misconception. Instead, it's actually heating caused by the immense air pressure that's created when an object moves fast enough through air. Is this true?

  20. Re:Well if I'm going to be obliterated by an aster by fyngyrz · · Score: 5, Insightful
    No, no -- you must be from some other earth. Here, we don't spend money on planetary defense, we spend it on sports figures, actors, and politicians. And porn, of course.

    --
    I've fallen off your lawn, and I can't get up.
  21. Re:meh by jc42 · · Score: 4, Informative

    Yeah. A couple years ago, I ran across an article that contained a graph of object size versus frequency of entering the Earth's atmosphere. The 1-per-day frequency was for objects of about 3 meters diameter.

    Several objects of this thing's size enter our atmosphere each week. Most of them disintegrate in the atmostphere. A few have pieces that hit the ground, though they're usually rather small by the time they (or the pieces) hit.

    To do serious damage, we'll need a rock at least a few hundred meters across. Of course, one of those may hit us next week. Or 10,000 years from now. (Or both. ;-)

    I wonder if I could find that graph again?

    --
    Those who do study history are doomed to stand helplessly by while everyone else repeats it.
  22. Define: Irony by HeliumHigh · · Score: 2, Funny

    My slashdot fortune cookie:

    "This is the tomorrow you worried about yesterday. And now you know why."

  23. well known cosmic blind spot? by zanderredux · · Score: 3, Funny
    how is it well known?

    I've never heard of it, until today!

    1. Re:well known cosmic blind spot? by Capt'n+Hector · · Score: 2, Informative

      It's known by people who work in the field. There are several other blind spots in astronomy, though:

      1) the moon (although the moon itself is only ~0.5" across, telescopes need to stay far away from it...
      2) the earth (jokingly for earth-based stuff, serious for space telescopes)
      3) the galactic plane (unless of course you're looking at stuff in the galactic plane...)
      4) andromeda (it's friggin huge!)

      --
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  24. Re:Might want to recheck the size ... by Rakishi · · Score: 2, Insightful

    2002 is different from 2004, I feel bad for your HS Math teacher.

  25. No they couldn't by BrianH · · Score: 3, Informative

    Despite what Hollywood would have you believe, ICBM's aren't designed to be launched into space and they have neither the thrust to propel a warhead out of our gravity well, nor the accuracy to hit anything smaller than 50km wide even if they did (and that's assuming that the asteroid is close). ICBM's were designed for one purpose...to put a small warhead within a few hundred yards of a stationary target less than 15,000 km away from the launch point. They are useless against moving targets hundreds of thousands of km away.

    There is nothing else we could throw at an incoming asteroid. The simple reality is that if we humans spotted a big rock coming at us, even with a month or two to prepare for it, all we could really do is dig a shelter, store food away, and pray that it comes down on the OTHER side of the planet.

    --

    There is nothing so pathetic as seeing a beautiful young theory roughed up by a tough gang of facts.
    1. Re:No they couldn't by BrianH · · Score: 2, Insightful

      I should have been more specific. We can predict where and when it would come down but the course alterations due to its entering the gravity well would probably prevent the exact point of impact from being determined until the weeks, and possibly even days, before impact. Prior to that you're not going to get any more accurate that "it'll come down somewhere in north or south America, the Atlantic, or the Pacific", or possibly "Europe, western Asia, or Africa".

      So yeah, the people on the side of the planet that it was coming down on would know that their hemisphere was about to be hit, but no more than that. And honestly...what good would that information do? Even if we could narrow the impact site down to a continent sized area like North America, do you really think we could evacuate the entire United States, Canada, and Mexico in that period of time? Where would those 400 million people go?

      Nope, our technology simply isn't advanced enough to allow us to deflect, or even evacuate before impact, if a truly siseable asteroid ever stuck the Earth.

      --

      There is nothing so pathetic as seeing a beautiful young theory roughed up by a tough gang of facts.
    2. Re:No they couldn't by esanbock · · Score: 2, Informative

      Evacuate them where? The skies would be darkened for years from the debris. Global famine would kill billions. Personally, I'm actually more worried about a supervolcano called "Yellowstone" taking out North America.

  26. Re:Tell that to Bikini Atoll... by BrianH · · Score: 3, Insightful

    Correct, a nuke detonated against an asteroid could conceivably break it up or change its course. It's just a shame that we don't have a delivery system with the range, speed, or accuracy needed to actually HIT an incoming asteroid.

    --

    There is nothing so pathetic as seeing a beautiful young theory roughed up by a tough gang of facts.
  27. Near-misses unnoticed by adam31 · · Score: 3, Funny
    But many near misses by small asteroids likely go unnoticed

    I think the Slashdot effect is very similar...
    submit a story, it gets rejected, and a server admin sleeps quietly through the night.

    One day... Mr Beer-Powered Robot Man. Just keep that site running......

  28. Frequent Close Calls by respite · · Score: 2, Insightful

    Is it just me, or does it seem like we have one of these each month.

    Are they becoming more frequent, or is it that we can monitor them more effectively now.

  29. Re:Tell that to Bikini Atoll... by SonicBurst · · Score: 3, Informative

    OK, I am totally guessing here and I'm sure I'm so far wrong it is funny, but I'll still say it anyway.... You point out that there wouldn't be any atmosphere. So, much less shockwave, since there isn't much there to carry it. However, the physical energy released by the bomb must go somewhere. Would it not be *more* focused on the asteroid, since it is the most available medium? Please don't flame me too bad for this wild speculation :)

    --

    Geek used to be a four letter word. Now it's a six-figure one.
  30. Re:Did this really fly under the radar, LITERALLY? by Mawbid · · Score: 2, Funny
    Well...

    It soared over Antarctica -- underneath the planet

    ...so I guess they're right after all :-)

    --
    Fuck the system? Nah, you might catch something.
  31. Not just friction by Tony · · Score: 2, Informative

    If you compress a gas, the temperature of the gas increases, When you expand a gas, the temperature of the gas decreases (which is why those compressed air cans get cold when you use them). Quite a bit of the heat generated by a meteor is caused by the compression of the atmosphere as the meteor enters the atmosphere. As the atmosphere re-expands behind the meteor, it cools back down; but the meteor is in a constant hot-spot.

    Friction does play a part. Heat is created as the potential energy of the meteor is converted to kinetic energy (due to acceleration as it loses speed with respect to the atmosphere).

    --
    Microsoft is to software what Budweiser is to beer.
  32. Re:Tell that to Bikini Atoll... by SuperBigGulp · · Score: 4, Funny

    Wrong. We have have an accurate delivery system in the form of Clint Eastwood, Tommy Lee Jones, Donald Sutherland, and James Garner.

    If we need a second chance, maybe they can get Lance Bass.

    --
    Someday a Slashdot ID of 177180 will mean something.
  33. Literally by UnpopularOpinion · · Score: 5, Insightful

    So... when you say 'literally', you mean 'metaphorically' right? As in not literally under a radar... *sigh*

    1. Re:Literally by CaptainAvatar · · Score: 2, Interesting

      Well, yeah, and there's also the fact that nobody uses radar to discover these things anyway. It's all done with mirrors - that is to say, optical telescopes.

      --
      The real Captain Avatar is a fictional character, so I suppose he doesn't mind if I impersonate him.
  34. Re:I would... by WIAKywbfatw · · Score: 2, Insightful

    I would think that even the least socially-gifted geek would have no trouble finding someone to screw if the world was going to end tomorrow.

    --

    "Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
  35. Obligatory Simpsons Quote by Brad1138 · · Score: 3, Funny

    Homer: "So there's a commet. Big deal. It'll burn up in our atmosphere and whatever's left will be no bigger than a Chihuahua's head."
    Bart: "Wow, dad. Maybe you're right."
    Homer: "Of course I'm right. If I'm not may we all be horribly crushed from above somehow."

    --
    If you could reason with religious people, there would be no religious people
    1. Re:Obligatory Simpsons Quote by LuckyPhil · · Score: 2, Funny

      (from same episode)

      Moe: Quick... lets burn down the observatory so that this never happens again!!

  36. Is this a problem? by HarveyBirdman · · Score: 2, Insightful
    This is like worrying about that dust particle that almost hit me when I was walking out to my var Monday.

    We don't have to spot the 16 footers.

    --
    --- Ban humanity.
  37. Re:Did this really fly under the radar, LITERALLY? by Euler · · Score: 2, Insightful

    It flew under the weather radar satellites - LITERALLY. There.

  38. Re:Tell that to Bikini Atoll... by ozmanjusri · · Score: 3, Informative

    To really do any good, one would drive the warhead into the asteroid before detonation

    No, that would just break it up and make it worse. Some fragments might be accelerated sideways enough to miss the earth, but more will be accelerated forward or backward along the asteroid's current path. The result would be like being hit by shotgun blasts as the earth rotated through the asteroid fragments.

    The total energy imparted to the planet by the asteroid would remain the same, but it would be spread over a greater area.

    A better idea would be to use a stand-off blast where the nuke is detonated alongside the asteroid to give it a sideways shove and deflect it whole, but even this would be extremely inefficient, and you'd need to identify the trajectories very early.

    NB, to the grandparent poster, the fact that the asteroid is the only object in the vicinity of the explosion would have no affect on the amount of energy it receives.

    --
    "I've got more toys than Teruhisa Kitahara."
  39. Re:Slashdot Article Completely Inaccurate by The+Cisco+Kid · · Score: 3, Informative

    There were two asteroids. The link labeled 'blind spot' was a link to an earlier, larger one. The link actually labelled '16 foot asteroid' described the smaller one.

    Both discuss the 'blind spot'

  40. Re:Tell that to Bikini Atoll... by ozmanjusri · · Score: 2, Informative

    There's a good chance that most, if not all of them will be too small to survive and even if some hit, it will be a number of small smacks, not one big WHAM

    I think the problems will be caused by energy being imparted to the earth by millions of tonnes of rock at high velocities rather than the impacts with the ground.

    What do you think the result of flash-heating the upper atmosphere to several thousand degrees for several hours is likely to be?

    --
    "I've got more toys than Teruhisa Kitahara."
  41. Re:Tell that to Bikini Atoll... by Demolition · · Score: 3, Informative

    Actually the old Nike Zeus/Spartan antiballistic missle from the late 60s early 70s might have the range and speed. But it is unlikly that it chould it hit far enough away to make a big difference.

    Probably not.

    The Zeus EX/Spartan had an operating ceiling of only 560 km (350 mi) and maximum range of 740 km (460 mi). I've read that the ideal range to intercept an asteroid/comet, so that its trajectory is altered enough to guarantee a complete miss, is 300 million km (186 million mi). That's because such an object would be travelling very quickly (as much as 60,000+ km/h) and we'd need a lot of lead time (at least a week) to figure out the object's composition and course, and prepare a missile/payload that could alter its course (or destroy it).

    In other words, I don't think that anti-missile technology from the 1950s (or even present-day technology, for that matter) is going to save us.

    D.

  42. Re:Well if I'm going to be obliterated by an aster by RobinH · · Score: 3, Funny

    And, don't forget: blowing pieces of this earth that belong to other people.

    Doesn't that fall under the porn category? :-)

    --
    "I have never let my schooling interfere with my education." - Mark Twain
  43. Re:Tell that to Bikini Atoll... by techno-vampire · · Score: 2, Insightful
    What do you think the result of flash-heating the upper atmosphere to several thousand degrees for several hours is likely to be?

    Several hours? How long do you think it takes a rock to fall through the atmosphere? Less than a minute or so. And, unless all the fragments go through the exact same spot one after the other, the energy will disperse. The reason you have to worry about the impact is that the energy is transferred to something solid (At those speeds water can be considered solid because it can't move out of the way fast enough.) and turns into shock waves.

    --
    Good, inexpensive web hosting
  44. Saw one Explode at Football Game... by also+aswell · · Score: 4, Interesting

    It was back in maybe 1965/66? Dark night with no moon, playing an away game of jv football in Albemarle? NC.

    That sucker arced across 20% of the sky with a really orange red tail and exploded. Almost looked like dawn was coming, I waited for sound, started counting off seconds to range it's distance, but no sound ever came.

    Just for a moment I thought it was the Russians, but that's another story.

    Something I will never forget.

    And some asteroids come even closer, entering the atmosphere. Most never reach the ground because they break apart under the stress of entry. One study of data collected by U.S. military satellites logged 300 in-air asteroid explosions.

    --
    "Where did this apple come from?"
    --Alan Turing
  45. Politician mocked for supporting asteroid research by FleaPlus · · Score: 4, Interesting

    It's interesting to note that when Congressman Anthony Weiner (D-NY) tried to introduce a bill to provide additional funding for tracking near-earth asteroids, he was mocked by some of New York Mayor Michael Bloomberg's aides. In general, supporting things like this (even though they're actually pretty important) is a good way to get yourself targeted for "not caring about things here on Earth."

  46. trailing right behind it by moosesocks · · Score: 2, Funny

    scientists have also acknowledged the presence of a second, nearly identical asteriod trailing directly behiDFJAFNDFK DJF *#%*# *****NO CARRIER*******

    --
    -- If you try to fail and succeed, which have you done? - Uli's moose
  47. Re:Tell that to Bikini Atoll... by Stealth+Potato · · Score: 4, Interesting

    Well, let's run some numbers, shall we?

    Warning! Gross oversimplifications and estimates follow! :-)

    For the purposes of this problem, we'll assume the ginormous million-year doomsday rock, a 1000-m diameter chunk of iron. A 1000-meter sphere of iron has a mass of 3.30 × 10^13 kilograms. At an impact speed of, say, 30 km/s (approximately Earth's speed of orbit around the sun), that rock has a total of (1/2) * (3.30×10^13 kg) * (3×10^4 m/s)^2 = 1.5 × 10^22 Joules of kinetic energy.

    Now, let's make some assumptions about the atmosphere. We'll assume the atmosphere is of uniform density, distribution, and composition, and about 120km high (not a terrible approximation, but not a good one either). The volume of the atmosphere is then (4/3) * pi * ((6.498×10^6)^3 - (6.378×10^6)^3) = 6.25 × 10^19 m^3.

    The density of air at sea level is approximately 1.29 kg/m^3, so the mass of our atmosphere is then (6.25×10^19 m^3) * (1.29kg/m^3) = 8.06 × 10^19 kg.

    If we assume the volume remains constant, the specific heat of the atmosphere is 716 J/kg*K, so the introduction of 1.5 × 10^22 Joules of energy will result in a temperature increase of dT = E / (m*s) = (1.5 × 10^22) / (8.06 × 10^19 kg * 716 J/kg*K) = 0.26 K

    So, in summary, a 1-km diameter asteroid made entirely of iron, travelling at 30km/s relative to the Earth, and assuming all the kinetic energy was converted to thermal energy and spread evenly across the entire globe, would raise worldwide temperature by less than half a degree celsius.

    Now, if we assume a rock like the one supposed to have extinguished the dinosaurs, i.e., a 10-km rock, which consequently has 1000 times the mass, then the global temperature change could be as high as 260 degrees celsius, which is where things really start cooking.

    If I made any slip-ups in my math, please point them out. It's entirely possible, since I didn't bother double-checking. Although I made so many liberal assumptions anyway that if you use these numbers for anything, you're crazy. This was more a diversion into the sort of problem you'd find in an elementary physics textbook than an actual scientific exercise. :-)

  48. Re:RTFA, SVP. by NetFu · · Score: 2, Insightful

    I think when it comes to this kind of crap, we have to be "in it for the species". Whether we're talking about a city of 100,000 or a city of 10,000,000, it's still just a drop in the bucket of 8-10 billion.

    If we could come up with a way to stop these things, how often would we NEED to, and how much would it cost?

    We need to pick and choose where we spend our money. I'm all for spending much, much more on scientific endeavors, but I'd rather spend the LIMITED amount of money we have on scientific endeavors that will accomplish something.

    Or maybe we could save more people (over the same time it takes to have one of these things hit a "city") by simply finding a way to stop wars?

    That'd be a worthwhile cause in my book. Inventing a vaporous 21st century SDI system is not...

  49. Re:Tell that to Bikini Atoll... by Benm78 · · Score: 3, Interesting
    I didn't check the calculations, but I see a few problems with the assumptions:

    We'll assume the atmosphere is of uniform density, distribution, and composition, and about 120km high (not a terrible approximation, but not a good one either).

    The atmosphere is not that thick really. There is atmosphere up to this height, but its density is minuscule at an altitude of say 100 km. If you would assume constant density, it would be safe to assume a thickness twice the altitude where pressure is half that at sea level. This equates to around 2*5km, since at 5km pressure is 0.5 atm, and 50% of the air mass is contained below this level.

    This would increase the temperature rise 60-fold, an increase of 15K... which would probably not kill us all, but would have great impact on life.

    On the positive side, much of the energy generated will be radiated into space (over half of all radiation produced is directed away from earth). As the whole process probably occurs at high temperature, much of the energy will be radiant.

    Finally, the other half of the radiant energy will strike the ground, heating up soil and water, increasing the total amount of mass that absorbes the energy.

    Pretty complex stuff ;)

  50. Re:meh by doktoromni · · Score: 2, Informative

    To do serious damage, we'll need a rock at least a few hundred meters across.

    It depends on what you call "serious damage". The Tunguska event blasted thousands of square kilometers of Siberian forest and it is estimated that it was a meteor just 60 meters wide.

    A similar impactor hitting a populated area would decimate a whole metropolis or even a small US state. I would call that "serious damage".

  51. Re:Truth stranger than fiction? by HeghmoH · · Score: 2, Funny

    West Wing jumped the shark long ago. With cardboard cutout characters like "George W. Bush" and "Donald Rumsfeld", I can't believe anybody ever took it seriously. The whole mess in "Iraq" (wherever that's supposed to be) has just been ridiculously long and drawn out, and is obviously just a lame recurring plot device to make up for the fact that their writers have no original ideas. They constantly introduce new major adversaries and then forget about them (anybody remember "Osama bin Laden" from the 2001 season, or "Saddam Hussein" from last year?) and in general it's just a gigantic farce. I'm surprised anybody pays any attention to it these days.

    --
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