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Space

Apocalypse Missed: Asteroid Near Miss 132

Erik Hovland writes: "The NEAT project at JPL found a nice big rock (about half a km). And it is going by earth at about 0.0317 AU, a close call by cosmic terms but definitely a miss. Still one of the closest encounters yet, glad someone is playing chicken little for us.Full story here." The chunk of rock has been dubbed 2000 QW7, and was spotted last weekend because of its speed and brightness. But rest easy, since "there is absolutely no danger of a collision." As if they'd tell us -- even now, I bet Bruce Willis and Liv Tyler are suiting up.
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Apocalypse Missed: Asteroid Near Miss

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  • If it were lotto, I'd buy a ticket.

  • tooth (me) said: I think this is the only experiment from Apollo that is still usable today

    I found a link that may be of interest: Apollo 11 experiment continues to return valuable data [xs4all.nl].

  • What we need is another unit of measure for close Earth distances, instead of Astronomical Units. AUs are fine for interplanetary distances, but confuse everyone when dealing with things that are closer.

    So I am suggesting the Moon Unit, the distance from the earth to the moon. In this context, the asteroid passes about 12.19 Moon Units from Earth, and the sun is 384.6154 Moon Units away.

    Point being, some people panic when you say 0.0317 AU, but would probably be more relaxed if you said 12.19 MU (Moon Units).

    - - - - - - - -
    "Never apply a Star Trek solution to a Babylon 5 problem."

  • given that the Moon is actually moving *away* from us.
    --
  • by roystgnr ( 4015 ) <roy&stogners,org> on Saturday September 02, 2000 @05:52AM (#809757) Homepage
    Not to rain on the chicken littles, but...

    Oh, don't apologize. It's not rain we're worried about falling from the sky...

    There's room for a lot of 1km chunks of rocks in .0317 AUs (3% of the distance between the earth and sun).

    Yup. Just the fact that we've seen this NEO (and a couple hundred other 1km rocks) pretty much means we can tell it's not going to hit us any time soon. Some of us worry about the thousands (based on the limited searches we've done and the density we've found there) of kilometer-sized earth-crossing asteroids we haven't seen, though. Not to mention the tens of thousands of "city killer" sized NEOs that are theoretically out there, but that we can't easily track.

    Hollywood got it wrong repeatedly; if we were to get hit by an asteroid, not only would it not have to be "Texas sized" to wipe us out or kill thousands, it wouldn't even necessarily be detected. We've had asteroids pass within a million miles of Earth, but only be detected *after* they went by.

    If we haven't had a serious hit in the last 2k yrs

    But we have. We had a "city killer" hit in Siberia last century, for example. God only knows what has hit the oceans or similarly unpopulated areas when nobody was watching.

    what do you think the chances of us getting one in the few years since we've had the technology to see them?

    Conservatively, about 1 in 2 million that we'll see a mass extinction sized event in my lifetime; about 1 in 20 that we'll see a "city killer" hit a moderately populated area in my lifetime. There are "in between" events to consider too, but that gives you the basic idea. Even wildly speculating, I'd guess no higher than a 10% chance that I'll see either. But when you consider that the damage from a nicely aimed city-killer could reach $10e12, and the damage from a multi-kilometer rock would be (from our point of view) infinite, the situation is still a little worrisome.
  • ...Deep Impact or Armageddon (exactly the same plot)
    <O
    ( \
    XGNOME vs. KDE: the game! [8m.com]
  • it's those dang martians throwing rocks at us again!!!
  • hey man, there's no need to brag.
  • How big does a rock have to be to get through earth's atomosphere? Obviously this will depenend of the composition of the meteor and where it lands, etc... but how big are we talking ballpark for something on the scale of say, a small nuke blast?
  • by Bruce Perens ( 3872 ) <bruce@perens.com> on Friday September 01, 2000 @09:23PM (#809762) Homepage Journal
    Consider how little a nudge it would take to make it hit us right on. I'm afraid I don't have the math for orbital mechanics, but my guess is that out by the apogee of its orbit it would take a very small angular change. How much force would it take? Are we talking about a small asteroid impact, a pass by a massive object warping its orbit, or what?

    Thanks

    Bruce

  • Got to thinking about how to detect astroids way off in space. OK, so the 4th root applies to detecting radiation off of an object (hey, it's just like calculating a flash picture) so the transmitter if using radar would have to be pretty powerfull. Granite does't have that great of a radar cross section, so you have to hit it with a lot of energy to get an echo at interplanatary distances. Iron and nickle would be a cinch, but we should worry about astroids that don't have metal in them.

    So what else could be used? Light? Well, OK, but what about low albedo (sp, sorry) objects? Use something like lidar? (Laser radar.) Again, low light reflection dictates high detection power.

    If we could detect mass somehow, that would be the way to go, but we can only detect mass at a distance by observing how it affects other mass as it passes.

    Well, radiation (and this means more than radioactive, it includes light, radar, ect.) would mean very high output power and very sensitive recievers, with long dwell time for speed of light delays.

    Any thoughts?

  • > Today's hasty cosmic visitor -- known by researchers as 2000 QW7 --
    > was discovered just last weekend on August 26, 2000

    This makes me wonder what sort of realistic contingency plan we have for reacting to such a thing within a week, if this is all the advanced notice we are going to get. And no, I don't count seeing Armageddon as adequate preparation.
  • This "nice big rock" is one-half of a kilometer in diameter. In perspective, that is not very big compared to the earth. To what extent would there be damage if a rock of this size actually did hit earth, and wasn't a miss of a mere .0317 AU's? (The asteroid, btw, is a very long distance away - about 12 times as far away as the moon, hardly what I'd call near.)
  • "If we haven't had a serious hit in the last 2k yrs what do you think the chances of us getting one in the few years since we've had the technology to see them?"

    Exactly! That's just what the asteriods want us to think. See, once we've spent all the world's nations' emergency budgets on asteroid-fighting equipment... that's when the Alien invasion comes!

    So, we've got to convince the world's leaders to save their Asteroids quarters for fighting Space Invaders instead!

    Hey! What're you all laughing at?!? This is a perfectly legitimate discussion here! We're even forming Political Action Committees as we speak! Now, if only we could find a good PAC Man...

    (Score: -1024, Grooaaaaannnnnnnn..., my head hurts...)

    At this point in time, Spurious George would like to apologize for the wholesale massacre of several beloved cheesy 80's arcade icons, and would like to squarely pin the blame on the aliens... Next time, we promise to wear our aluminum wrap helmets, to, ahem, "foil" the alien mind control devices...

    (Loud "WHAP" noise, followed by the sound of slimy space creatures slurping and crunching the remains of Spurious George's mangled corpse. Audience cheers. Momentarily. Then the dark shadow of a near-Earth asteriod appears overhead. Panic ensues. Loud "crunch" noise. Audience's response is justifiably lukewarm. The End. Don't say we didn't warn you.)

    --
    while ( !universe->perfect() ) {
    hack (reality);

  • Ultimately, the scariest aspect of this is to be reminded we don't have an organized program monitoring for killer asteroids. While forewarning might make that big of a difference if we don't have the technology to divert/destroy/deflect the asteroid, at least other types of precautions could be taken.

    With all this talk about a Missile Defense program which is almost completely pointles s [stygianlabyrinth.net], I'd be more interested in a asteroid defense system.

    On a side note, with all the treaties against space based nukes, has any country ever tested a nuke in a vacuum? Maybe that would ignite our atmosphere and in a Twilight Zonian twist, the asteroid wouldn't hit the earth and we would have been destroyed by our own ignorance. Or not. Depends who is writing it and who is producing.

  • I'm sure that Moon Unit Zappa would appreciate the usage -- she's been out of the public eye for over a decade. Being the "celebrity" spokesperson for a unit might be a good gig.
  • You mean, how many have collided and seriously disrupted life on earth? None within recorded history, much less modern history.

  • I don't really ever see us stopping that 10km wide thingy coming at us at 100,000km/h, at least not with the technology today, perhaps when we develop technology to bend space-time on a planetary scale the odds will be better..

    Personally, I'd rather see us become more aggressive in our attempts to colonize other worlds as means to insure our survival as a species.

  • I don't know much myself.. but I think it depends on more the SPEED and SIZE than just plain ol' size.

    So it is more than just size that matters. ;)
  • You mean, how many have collided and seriously disrupted life on earth? None within recorded history, much less modern history.

    None within recorded *human* history. If the theory is true that the dinosaurs were killed off by an asteroid (I'm not saying that it is or isn't true), then your argument here proves false.

    =================================
  • Hate to break it to you.. but that "face" upon closer inspection turned out to be a more natural random formation of rocks that look nothing like a face.

    The human brain has a very large section specifically for perceiving faces. It hunts for faces in the visual field, and will spot them in virtually any pattern that vuagely suggests a face. It also attempts to identify identity, emotion, and a number of other factors.

    So everywhere we look we see faces - in light sockets, on the lids of cans of grated parmesan cheese, and in the shadows of topographic features on Mars.

    One description of this effect, and an interesting exercise utilizing it, occurs in the book "understanding comics" by Scott McCloud. The exercise:

    - Draw a random squiggly closed curve. (Think "amoeba".) It looks like a random squiggly closed curve.

    - Add an "eye" composed of a small circle with a dot in its center, somewhere inside the closed curve (preferably near an edge). Now it looks like a "comic book" head.

    As for Mars: Shortly after the "Face on Mars" flap started NASA published another photograph from the same probe, which had found a feature that might as well have been a deliberate sculpture of Kermit the Frog.

    IMHO there is enough interest in the "Face" site (both by believers and debunkers) that NASA should spend a little of a probe's time to re-image it, and publish a radar topographic probe and reflectivity map.

    Plug that into some existing software and you could do a virtual flyby and walkthrough of the site. You could set the viewpoint and illumination to replicate the original image (to see that it was the right spot), then wander over and around it, illuminating it from other angles, to see what it's really like.
  • Earth's atmosphere cannot be ignited. A reaction to produce nitrogen oxides from air would require too much input energy. Besides, a nuke in vacuum is still a nuke. Just a big flash of energy and no hit wave, so it would do very very little physical damage.
  • no, what i meant is this: according to some organazation, i forget their name, we only activley scan 40% of our sky for astroids and comets, etc. (forgive me if im off, im saying this from memory)
  • they move in the night sky because THE PLANET ROTATES.

    And so do all the sagans-and-sagans of "fixed stars". So how do you differentiate the incoming object from J. Random Ordinary Nova?

    If you're VERY LUCKY you spot it while it's still far enough out that the orbital mechanics makes it appear to move slightly relative to the stellar background. But when it's far out it's a lot dimmer, looking like the rest of the asteroidal junkpile. It doesn't take a very big rock to create an extinction event.
  • Ultimately, the scariest aspect of this is to be reminded we don't have an organized program monitoring for killer asteroids.

    Didn't you follow the link to the ? What do you think found THIS one? [nasa.gov]

    You might argue that it's underfunded, will take too long, might miss something significant, might not spot a collider in time to do something about it, or that it will only spot asteroids and not comets (or at least not in time).

    But I recall a decade ago when we DIDN'T have such a project in place AT ALL and I'm MUCH happier with the current situation.

    Every time they spot a new one that comes anywhere near close enough they get another opportunity to publish an estimate of the number they HAVEN'T found. A nice argument for a few more bux for telescopes and observers.

    Just think: If we stop one extinction-event rock, humans and technology will have prevented vastly more environmental damage in a single operation than has been caused by all the humans since we first appeared. Take THAT, Earth First!
  • The Meteor Crater in Arizona was caused by a nickel asteroid only about 30 meters across, if you want some perspective. But one that size won't be visible until it's right overhead and it's too late to do anything about it.
    • First of all, 0.03 AU is quite far away. If 1 AU = 150 * 10^6km. 0.03 AU = 4.5 * 10^6 km, which is 5 million km. There were FAR closer misses before (there was an asteroid that missed Earth by 200,000km.
    • I don't believe we can do ANYTHING destructive with a chunk of a rock this size. Nuclear bombs don't do so well against solid matter. So it seems to me that it would be better to try to deflect an asteroid from its course (even one degree at 10^6km will deflect the course by 10^6 * tan 1 ~ 17,000 km (more than Earth's diameter), persuming that the trajectory is relatively straight. This could be done by putting an many ion thrusters on the surface of the asteroid, and activating it for a period of many years. So, while this is definitely not as spectacular as a nuce, it will be far more effective.
  • by Captain Pillbug ( 12523 ) on Friday September 01, 2000 @09:38PM (#809780)
    (and paraphrasing off the top of my head). From the site [permanent.com]:

    The exact damage inflicted by an asteroid or comet depends upon a number of factors -- size, speed, composition of object, and whether it hits land or ocean. (HDCA, paper ref.)


    For a land impact, it can be said in general that an object of roughly 75 meters diameter can destroy a city, a 160 meter object can destroy a large urban area, a 350 meter object can destroy a small state, and a 700 meter object can destroy a small country.

    For an ocean impact, the destruction is much greater -- smaller objects can cause far more widespread damage. The effects of an ocean impact are felt much further away than the effects of an airburst due to the more effective propagation of water waves, and the fact that human populations and assets are largely concentrated in coastal cities which historically became established due to water transport (i.e., shipping and trade) and businesses near ports.

    For example, the earthquake-induced tsunami in Chile in 1960 produced waves in Hawaii 10,600 km away of height up to over 10 meters (30 feet), and up to 5 meters (15 feet) in Japan 17,000 km away with an average of 2 meters, causing heavy damages and loss of lives.
  • Is that REALLY a close call?

    These things just don't go past once and then leave, they *ORBIT* the sun. Guess what that means? They cross earths orbit twice for each one of their "years"

    That means the chance of a collision incresses with time. How many of these "small" rocks that cross earths orbit are there? Who knows...

  • > but how big are we talking ballpark for something on the scale of say, a small nuke blast?

    I don't know much myself.. but I think it depends on more the SPEED and SIZE than just plain ol' size.

    The worry of something hitting us is that it could create a wave that would create a large enough earth quake to disrupt the 'thin' crust that seperates us from the lava we float on. =)

    My beef about this story is why is it I ONLY heard about this on slashdot?? I did NOT see this in the News cast, nor the NPR Broadcast this morning nor on the way home from work, nutin. Not like it was a totally close call, but heck it wouldn't take much to spin things off like this our way.

    Seriously, they saw it a week ago, why couldn't they even mention it somewhere to the masses? It might be on the front page this morning.. It's 11:56pm right now (for me in AZ) ..

    -- life is short, buy nike.
  • I realize that this is a joke, but removing Jupiter would make Saturn and Earth the closest gravity wells to the asteroid belt (Earth being closer). This could create some problems for us.

    The delicate balance of the Solar System took billions of years to establish, and I wouldn't want to mess with that.

  • by Cebert ( 69916 )
    Question...how come we can go thousands of years without looking into the sky, yet all of a sudden, because we're looking, we're finding all this shit "coming close"? Just seems too much of a coincidence.
  • AARGH! Hit the wrong button. Let's try again...

    Ultimately, the scariest aspect of this is to be reminded we don't have an organized program monitoring for killer asteroids.

    Didn't you follow the link to the NEAT project [nasa.gov]? What do you think found THIS one?

    You might argue that it's underfunded, will take too long, might miss something significant, might not spot a collider in time to do something about it, or that it will only spot asteroids and not comets (or at least not in time).

    But I recall a decade ago when we DIDN'T have such a project in place AT ALL and I'm MUCH happier with the current situation.

    Every time they spot a new one that comes anywhere near close enough they get another opportunity to publish an estimate of the number they HAVEN'T found. A nice argument for a few more bux for telescopes and observers.

    Just think: If we stop one extinction-event rock, humans and technology will have prevented vastly more environmental damage in a single operation than has been caused by all the humans since we first appeared. Take THAT, Earth First!
  • it is going by earth at about 0.0317 AU, a close call by cosmic terms but definitely a miss.

    I disagree with the characterization of 3% of the distance between the Earth and the Sun as a "close call". I'd save it for things that come a LOT closer - like the big one that passed inside the orbit of the Moon in the last decade or so.

    But rest easy, since "there is absolutely no danger of a collision." As if they'd tell us

    But they DID tell us last time they had one where the preliminary figures put the Earth inside the uncertainty boundary of the initial orbital calculations. ("They" in this case was a researcher, not NASA administrators {who didn't even know about the object yet}.)

    It caused a flap, and maybe the researchers won't be so quick to talk to the press NEXT time. But once an object is spotted a call goes out to astronomers all over the world for possible previous spottings, to refine the orbit. That's a big audience (and includes lots of amateur comet spotters). Once the numbers are out anybody with the tools can crunch their own confirmation and/or look at the object in the sky and make their own measurements. So I wouldn't sweat being kept in the dark.
  • You are right with your first sentence,
    the astroid was only discovered a view days before.

    But your conclusion, we would not see it and it
    would just get larger is false.

    It's no problem to have an asteroid comming from
    a random point on a random course crossing the
    earth orbit just at the moment when the earth
    is at the crossing.

    In fact most asteroids just have a course like that.

    Imagine an asteroid with aphel nearer to sun
    then earth and perihel farer away from sun as
    earth.

    Ther are at least two crossings (in 2D space,
    in 3D space there might be no crossing!)

    Depending on your distance to the crossing,
    earth and the asteroid approach in a 90 angle
    to that crossing.

    However, you can turn the orbits of the asteroid
    and the earth in a way you like and get
    nearly each angle from 0 two 90, but as
    fas as I know not greater because all
    bodies orbit into the same direction.

    Regards,
    angel'o'sphere
  • Yes. It is actually f=mv^2. Very different, considering that these things are whipping around and the 30,000 (17,000 mph) kph range. Another interesting point is whether or not the thing is solid, a lump of gravel, porous. Very important to know how it's going to react when we hit it. An interesting question is what would happen if it shattered? Would a shotgun blast of material be as lethal at a large stone?
  • I remember a segment on Space (Canada's Scifi network) where they put two balls on a field and started hitting tenis balls between them, with a baseball bat. Chunks of rocks, even HUGE chunks of rocks are very small in comparison to even the distance between the earth and moon.
    Yes, but balls don't have significant gravitational fields, pulling tennis balls closer and closer on each orbit.
  • We probably don't need to be too worried about a complete extinction, Armageddon like, asteroid - the chances are very small. There have been a significant number of smaller asteroid strikes though.
    It's perhaps less likely now than it was 15-20 years ago at the height of "Cold War" paranoia,, but it's still possible that someone might mistake a "small" asteroid/comet impact for a nuclear first strike and launch a retaliatory strike.
  • One example: Shoemaker Levy 9
    Wellll... that's a comet, but Jupiter still gobbled it up.
    ---
    Mouse location changed. You must restart Windows for the changes to take effect.
  • Out of curiosity - how does this work anyway? Is it the _average_ distance between the earth and the sun? There's no way it is always the same distance, unless the earth's orbit was perfectly circular.

    --
  • Just put your head between your legs and kiss your ass goodbye.
  • Heh. I make sure my mom and daughter [perens.com] give me some of that every night!

    Bruce

  • The new national missile defense will protect us from these stupid rocks. NMD is the answer - it will shoot lasers and blow up the rocks, thereby providing alternative entertainment for those bored of the regular TV sitcoms.

    w/m
  • by Sir_Winston ( 107378 ) on Friday September 01, 2000 @09:46PM (#809796)
    "As if they'd tell us -- even now, I bet Bruce Willis and Liv Tyler are suiting up."

    Script suggestion for *Armageddon II: Liv Lives*; Scene !!!, Liv and NASA Geek in her dressing room just before flight.

    "Liv, can I zip you up? Please?"

    "Umm, no, you little geeky pervert. You and that puny little Perl script you have the nerve to call an application can get the hell out of my dressing room. Don't even *think* about *applying* that thing to me."

    "No, don't worry I've already seen them in that topless scene you did in *Stealing Beauty*. I'm not trying to cop a peek or feel, I just want to help you save the world from that asteroid through whatever highly unlikely and unscientific methods those hack screenwriters have dreamt up without consulting technical experts who didn't get their degrees from Joe Bob's College of Astrophysics and Auto-Repair."

    "Oh. Okay, then, zip me up."

    "Wow, your lips are so much more beautiful and soft-looking in person. They're just like Julia Roberts' lips, only on an *attractive* face."

    "Oh my God, is that a slide rule in your pocket or...ohh, we have to bring you with us! Maybe the sight of your enormous..."T-square"...will scare the asteroid away into a more elliptical orbit! Or at the very least our all-female crew can ravage you in a desperate attempt to cover up for poor screenwriting by depicting lots and lots of gratuitous sex!"

    "But what about Bruce Willis, he's part of your crew too?"

    "Well, he gets to ravage you too. It's in his contract."

    "Umm, err...okay, you're worth taking it in the ass from a deranged scientologist foolish enough to divorce Demi Moore's breasts. I mean, Demi Moore."

    [Kissing and groping]

    "So, you like my lips, NASA geek. Everyone does. It's the one thing I got from my Dad--well, that and Alicia Silverstone; we used to share her on alternate Thursdays."

    "Oh no....that's right you're...Steven Tyler's daughter! I forgot! Oh, my God, I can't look at those luscious lips without thinking about your dad. Oh no, it's like kissing Aerosmith! Acchhh, I'm going to be sick! I feel like I just made out with Aerosmith...gross..blechh....barf [much vomiting. NASA geek exits stage left, leaving a trail of vomit and shouting "Nooooo, I just made out with Aerosmith! Yuck!]

  • by quux26 ( 27287 ) on Friday September 01, 2000 @09:47PM (#809797) Homepage
    "If we haven't had a serious hit in the last 2k yrs what do you think the chances of us getting one in the few years since we've had the technology to see them?"

    Do you mean "What are the chances of us getting hit with a rock that will end all life on the planet if not the planet itself"? Then the answer is non-zero.

    We shouldn't overstate the liklihood, but we should not understate the consequences of that unlikeliness. After all, the dinosaurs did become extinct because they didn't have a space program (Sagan, I believe).

    My .02
    Quux26

  • God I would love that. My life is a complete hell right now. I had this really ugly baby boy (or was it a girl?) and I ain't gettin any from the Mrs.

    Thanks

    Bruce

  • Which movie? Do you want to go to the movies with me? I have no friends.

    Thanks

    Bruce

  • Not to mention blowing a planet into little bits would do little if anything to affect its gravitational influence on its surroundings, since you'd still have the same amount of mass with the same center of gravity.

    But then, you have to break a few eggs to make an omelette.
  • jeez. from now on, I promise to remember to log off of slashdot *before* I leave the computer lab

    --
    while ( !universe->perfect() ) {
    hack (reality);
  • Given that fact, having the moon decide to move closer would be all the more horriffic
  • Perhaps they've been shooting by all the time but we've only just started noticing- the car that splats a bug isn't the first car to drive by. Tunguska, 1908, is a recent possible impact site. The theory is a 60 metre asteroid blew up in the atmosphere 5 miles above Tunguska, in Siberia. It didn't even make it to the ground, yet the 15 megaton equivalent explosion flattened the forest for thousands of square miles, and the seismic shock was felt in London. Hardly a world shattering event, but it would have been pretty devastating over a builtup area.
  • I was more or less making fun of the people who see catastrophe regarding each and every man made event.

    But thanks for the illumination in regards to the subject.

  • Let's just call it a 'Zappa'...abbreviated as 'Z'. the Moon is 1 Z away from the Earth. :)
  • <I>The delicate balance of the Solar System took billions of years to establish, and I wouldn't want to mess with that.</I>
    <P>

    The delicate balance of the Solar System!?!?
    Are you freaking kidding me? It would take a wandering planet or brown dwarf to upset this 'Delicate Balance'
    <P>
    To sum, even if we tossed all of the nukes known to man at Mars, you'd get a nice light show, and a lot of glass souvenirs, and that's it.
    <P>
    Later
    Erik Z
  • The delicate balance of the Solar System took billions of years to establish, and I wouldn't want to mess with that.

    The delicate balance of the Solar System!?!? Are you freaking kidding me? It would take a wandering planet or brown dwarf to upset this 'Delicate Balance'

    To sum, even if we tossed all of the nukes known to man at Mars, you'd get a nice light show, and a lot of glass souvenirs, and that's it.

    Later

    Erik Z

  • We all know how much of an "expert" Kaku is about catastrophes as he predicted that Cassini would bring about the end of the world.
  • Here's a great site with info about this asteroid: http://meteors.com
  • Our moon is 3476 km in diameter and is constantly 0.0026 AU from the Earth

    Imagine if it eventually got tired of being 0.0026 AU and decided to come closer. Hrmmm... I wonder if we have any special telescopes continually observing the moon.

  • Would you want your daughter dating an earth-crossing asteroid?

    Hell no! I wouldn't want her dating a nigger, either.

    Thanks

    Bruce

  • At that size, if it hit land, then it could wipe out a small country and begin to disrupt global weather patterns. If it hit the ocean, then the resulting Tsunami could do even more dammage.
  • by tooth ( 111958 ) on Friday September 01, 2000 @09:58PM (#809813)
    [sorry for any typos]

    The Earth is a lovely and more or less placid place. Things change, but slowly. We can lead a full life and never personally encounter a natural disaster more violent than a storm. And so we become complacent, relaxed, unconcerned. But in the history of Nature, the record is clear. Worlds have been devastated. Even we humans have achieved the dubious technical distinction of being able to make our own disasters, both intentional and inadvertent. On the landscapes of other planets where the records of the past have been preserved, there is abundant evidence of major catastrophes. It is all a matter of time scale. An event that would be unthinkable in a hundred years may be inevitable in a hundred million, Even on the earth, even in our own century, bizarre natural events have occurred.

    In the early morning hours of June 30, 1908, in Central Siberia, a giant fireball was seen moving rapidly across the sky. Where it touched the horizon, an enormous explosion took place. It levelled some 2,000 square kilometres of forest and burned thousands of trees in a flash fire near the impact site. It produced an atmospheric shock wave that twice circle the earth. For two days afterwards, there was so much fine dust in the atmosphere that one could read a newspaper at night by scattered light in the streets of London, 10,000 Kilometre's away.

    -- Carl Sagan, Chapter IV "Heaven and Hell", Cosmos (ISBN: 0-349-10703-3)

  • by Anonymous Coward
    "Corner cubes" is the official name, although a more appropriate one would be cube corners. Take any three mirrors and arrange then perpendicular t o each other, like the inside of the corner of a mirrored cube. A little simple geometry will tell you that any beam of light that is close enough to the corner to bounce off of all three mirrors will come back exactly parallel to the direction it went in. Thus you can get a reflection back no matter what direction the cube (or in NASA's case, the array of cubes) is facing. It's completely passive and only requires that you know what spot on the moon to aim the laser at.

    Corner cubes are funky to play with. If you look at one with one eye closed, your pupil will always appear exactly at the corner no matter how you twirl the thing around.

  • The next time this paticular "object" will be comming close will be September 21, 2109.

    And that will be 0.043 AU which is FURTHER away than the one that happened yesterday (Sept. 1, 2000).

    (IF they are correct about it's current orbit, if they are SLIGHTLY off on the orbit, we could all be toast.. j/k..
  • This following the Martian Metorite [slashdot.org]

    Let me postulate a theory:

    1. There was life on Mars. One of their largest structures, which only partially survived, was a face.

    2. The Martians thought, "The danger from the sky will never hit us," and 200 million years ago they didn't see it coming.

    3. The impact was so great, they all perished; so great, in fact, that it blew chunks of the planet into Earth's path.

    4. The building blocks of life were contained in ... Nah, that's going too far. ;-)

    Nice conspiracy theory, even without 4. This tells me we need to devote more resources to our "eyes."

    Thing 1

    --

  • "Let's wait to find something that is going to hit us before we start panicing. Sure, go ahead, develop tracking and interception technologies, that's only prudent, but it's not front page news."

    I agree, but how do you educate the public about an impact with a rock that will turn the air to fire, possibly fracture or obliterate the planet and cause our home to become as sterile as a Backstreet Boys liner note without inciting fear?

    I understand what you're saying - we don't want to shoot ourselves in the foot about this (like we did once already) - but public funding sucks. I don't see how you bring this to people's attention w/out being accused of the Chicken Little/Cassandra complex.

    My .02
    Quux26

  • Don't listen to him! It's them Aliens talking!

    --
    while ( !universe->perfect() ) {
    hack (reality);
  • Funny thing is, we can't predict this stuff in advance. Of all the civilian technology I've been privy to, nothing will give us much more than a days warning of a NEO. Glare from the sun, as well as the fact that the asteroids don't radiate anything (glow) combine to make it hard to spot them. And that's all based upon the assumption that we're looking at the precisely correct portion of the sky at precisely the right moment. Keep in mind that space is big (real big,) and it gets harder to find things the farther they are away from the planet.


    {|}---Tony Hagale -- tony@hagale.net -- http://tony.hagale.net
  • We probably don't need to be too worried about a complete extinction, Armageddon like, asteroid - the chances are very small. There have been a significant number of smaller asteroid strikes though. There was one in Northern Siberia in the early 1900's that flattened an area roughly the size of Greater London (2000 square kilometers or so bigger than many cities). There have been 2 or 3 others in the last thousand years or so as well, but I can't remember where. With a greater world population and cities that are more spread out then their is a chance that the next one will get a fair few people. No it's not worth insuring your house against, bu it is more likely than global extinction.
  • ...someone's *finally* shooting Bruce Willis into space?

    - A.P.
    --


    "One World, one Web, one Program" - Microsoft promotional ad

  • (Disclaimer: these numbers should be taken within a fudge factor of 10!)

    10! = 3628800

    I'm sure you can be more accurate than that ;-)

    Woz
  • The Gamblers' Fallacy only holds for events that can truly be considered "random," such as dice roll results or coin flips. The physical distribution of asteroids (combined with the other factors that increase or decrease the likelihood of a convergence with our own coordinates) is not purely random. In a purely random distribution, it would be possible for all belt asteroids to exist in one tight cluster, whereas in real life such a distribution would be so unstable that it would either coalesce into a single body or more likely break apart into a more entropic distribution in short order.

    I don't know how apt an analogy this is, but: Think of two consecutive poker hands separated by a significant shuffle. Since the more ordered groupings that result from the first hand are returned to the deck intact and then shuffled, it is far less likely that you'll draw a hand identical to any of the first dealt hands than it would be to draw the given hand from a fresh deck. Hence the cards do have a memory of sorts, or perhaps more accurately, a short-term amnesia.

    IANAM,
    Ludwig
  • one substantial hit in 1,000,000 years. That gives you the odds of an asteriod hitting you tommorow of 1 in 365,000,000
    But it would kill 5,000,000,000 people. That's an average of 5000 every year.
    So the chance that an asteroid kills you beats the chance that an airplane-crash kills you.
  • Eh? The logical conclusion is that these asteroids have been coming "close" all this time. We just didn't know it because we weren't looking.

    We have plenty of geological evidence that sometimes they hit. The results can be fairly local for small objects and extinction level in other cases (bye bye dinosaurs!)

  • ...even now, I bet Bruce Willis and Liv Tyler are suiting up.

    You know, all these porklips movies represent a danger in their own right. When the Big Rock (or the Deadly GM Weeds, or whatever it was God used to deal with the Mastadon and Spiro Agnew) finally puts in an appearance, will people just shrug and say, "Hey, I saw the movie. This is even less convincing!"

  • man this is 3 times now every time i get on top of my car and start curseing for it to bring it on and every time the end is to much of a wuss to mess with me, either that or the sight of me naked on top of a car curseing with a bottle of tequila in one hand is to much for it bear :)
  • a near hit? A near miss, it seems to me, would be a hit.

    Oh God, it nearly missed us!.

    Stealing blatently from George Carlin.

    --- Never hold a dustbuster and a cat at the same time ---

  • This sounds a little like the classifications of civilizations by energy consumption, originally described by the Soviet astrophysicist N.S. Kardashev:

    Kardashev Level 1 - civilizations using the entire power output of a planet

    Kardashev Level 2 - civilizations using the entire power output of a star

    Kardashev Level 3 - civilizations using the entire power output of a galaxy

    Our own civilization is still somewhere under the K1 level. Getting to K2 would require something along the lines of a "Dyson sphere" to collect the energy output from the Sun, especially that above and below the plane of the ecliptic (which is currently radiated away from anything in the solar system which could use it).

    Oddly, Kardashev did not extend his analysis beyond galactic scale. Perhaps he thought that getting to K3 level would be a big enough challenge :-).

    Relating the Kardashev scale to Kaku's scale...a K1 civilization would probably be somewhere between 0 and 1 on the Kaku scale. K2 civilizations would probably be between 1 and 2, and K3 civilizations would probably score between 2 and 3. So there's a good correlation. (I agree, a civilization that scored 4 or 5 on the Kaku scale would probably be so far beyond our comprehension that it would be impossible for a mere 21st-century human to comprehend...)

    Eric
    --

  • by Neandertal ( 126319 ) on Friday September 01, 2000 @10:11PM (#809836)

    Its nothing new to most people that a catastrophic impact is just a matter of time. Tomorrow, next year, whatever. And if its not a meteor or asteroid, it could very well be a large volcano, etc. Regardless, the survival of our species will be threatened.

    I highly recommend Michio Kaku's "Hyperspace". In this book Kaku describes a very real and valid method by which we can classify a civilization based on its understanding of physics, even though we have no data points besides our own. This understanding of physics will have a direct result on how any civilization utilizes energy in surviving a variety of inevitable crisis.

    This is from memory, so it could be totally wrong. But, you'll get the idea:

    0. Level Zero. This civilization depends on natural energy deposits in its environment. It is unable to survive a large scale disaster, despite any technical or artistic accomplishments it has achieved.

    1. Level One. This civilization is able to harness true sources of energy production on a large scale, as opposed to only harnessing local energy reserves. The only true source of energy in the universe is fusion. This could be in reactors, or in some clever harnessing of a star. A level one civilization will be able to utilize and direct enough energy to survive a planetary disaster. This could be by diverting the disaster, or by relocating enough resources to a safe area of a solar system and rebuilding.

    2. Level Two. This civilization can utilize and produce enough energy to survive a solar system disaster. This could be a massive solar flare, death of a star, or destruction of the solar system by interstellar collision between neighboring stars, supernova, etc. Survival of such a disaster would imply the ability to manipulate a planet or star, or the ability to move about a group of solar systems with relative ease. Planetary engineering and terraforming would be taught in the freshman physics lab class.

    3. Level Three. A black hole is sucking up half the galaxy? No problem, these guys will move to the other side of the galaxy, or, maybe they would move the black hole to a safer place.

    4. Level Four. All the resources used up in the galaxy? No problem, we'll go find more useful galaxies to plunder. Traveling about the universe would be no problem.

    5. Level Five. The universe has existed for so long that protons are starting to decay. The universe is coming to an end - either in the big crunch - a repeat of the big bang, or the big chill - matter in the universe expands to the point of oblivion, kinda like a fart in a wind tunnel. A level 5 civilization would step into a different universe, or would engineer their own.

    From our perspective, a level 5 or 4 civilization would look like the Kingdom of God. We probably wouldn't comprehend it.

    A level 3 civilization would be something like Isaac Asimov described in his Foundation Trilogy.

    A level 2 civilization would be like Star Trek or Star Wars.

    A level 1 civilization would be like the early episodes of Star Trek.

    A level 0 civilization would be like the dinosaurs that used to roam the earth, and its current inhabitants of strangely naked apes, otherwise known as humans. We're not even close to being level 1. Our economies are so dependent upon oil that its sad, and we have no idea whats going on in our own solar neighborhood. We're trying though. With any luck we'll get to level one before mother nature or our own stupidity does us in.

    -Neandertal

  • Probability of hitting earth for an asteroid closer within the .0317 AU range: (Re = radius of earth, Ra = radius of asteroid)
    pi*Re^2
    ------- = one chance in 560,000
    pi*Ra^2

    Though it's not likely a certain asteroid hits earth, with about 50 such asteroids every year, let's expect the earth to be hit by this kind of (large) asteroids about every 10,000 years! That's quite often compared to the age of the earth.

    (Disclaimer: these numbers should be taken within a fudge factor of 10!)
  • If you want to get a feel for the probabilities, you might want to read Rain of Iron and Ice [ssi.org] by John S. Lewis. A section of the book gives the results of multiple computer simulations of the chances of the Earth being struck by various size objects as fictionalized descriptions of the results. Many large objects can hit the ocean without being noticed, except by any sailors unlucky enough to be in the area.
  • Crazy idea for a business: collect $1000 from people in return for a place in a queue [?] [everything2.com] for getting asteroid names [uni-heidelberg.de]. Use the money to pay for the operation of an observatory. Send asteroid data to the Minor Planet Center [harvard.edu]. If the observatory is the first to spot an asteroid whose orbit is later determined, we choose [umd.edu] a name for the asteroid based on the name of one the contributors in our queue.

    Of course, this only works if you can find lots of people crazy enough to pay $1000 to get an asteroid named after them. But just think: you could get your name on the doomsday asteroid!

    --

  • If we could detect mass somehow, that would be the way to go, but we can only detect mass at a distance by observing how it affects other mass as it passes.

    just a few thoughts... I'd say that when (if?) we can detect a gravity field directly, I doubt that we could use it for this sort of thing in the near future (+200 years). The Earth and Sun would swamp any mesurments we tried to make. Comparing to early radio astronomy and stuff like that.

  • And they measure that distance continuously. It used to be true that the Earth-Moon distance was known with better precision than the distance between London and New York, in fact.

  • Vincent Courtillot's book Evolutionary Catastrophes [dannyreviews.com] pretty much convinced me that mass extinctions on Earth have been due to volcanic events, not meteorite impacts.

    I don't know if that makes me feel more secure, though, at least we can see the asteroids coming, but our understanding of mantle dynamics isn't up to predicting Deccan Traps style volcanic events yet...

  • I just finished reading "Hammer of the Gods" by Clarke -- definitely a bit higher level than Armageddon. While certainly the society there is a bit more advanced than our current one, Clarke does give a good sense of scale -- such as long *long* sub-light speeds take to get from point A to B in the solar system, and just how much damage something small at those speeds can do.

    And besides, it was worth it to get to a quote in the epiloge: "A meteor hit a parked car in New York City -- what else was it going to hit?"

  • by JoeShmoe ( 90109 ) <askjoeshmoe@hotmail.com> on Friday September 01, 2000 @09:03PM (#809850)
    Uh, Tim...if anything Liv Tyler did some suiting down in that movie.

    - JoeShmoe

    -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -=-=-=-=-=-
  • by Minupla ( 62455 ) <`moc.liamg' `ta' `alpunim'> on Friday September 01, 2000 @09:04PM (#809853) Homepage Journal
    Not to rain on the chicken littles, but...

    There's room for a lot of 1km chunks of rocks in .0317 AUs (3% of the distance between the earth and sun).

    I remember a segment on Space (Canada's Scifi network) where they put two balls on a field and started hitting tenis balls between them, with a baseball bat. Chunks of rocks, even HUGE chunks of rocks are very small in comparison to even the distance between the earth and moon.

    If we haven't had a serious hit in the last 2k yrs what do you think the chances of us getting one in the few years since we've had the technology to see them?
    ----
    Remove the rocks from my head to send email
  • by Captain Pillbug ( 12523 ) on Friday September 01, 2000 @09:04PM (#809854)
    Gravitational nudges by Earth, Mars or Jupiter can potentially set such asteroids on a collision course with our planet, says Yeomans.

    That's the last straw. It's for precisely this reason that we as a nation (needn't be specified -- you know who we are) must fulfill our manifest destiny and blow Mars and Jupiter up off the face of the earth. I don't care whether we have to blow them into a billion little asteroid-sized pieces, and I don't care that Jupiter is primarily gaseous in character. We defeated the British, the Mexicans, and the Vietnamese, er, umm, I mean the Evil Soviet Empire, so the least we should be able to do is destroy two unsuspecting and poorly defended planets.

    Just think of all the money we'll save by not having to fund manned missions to explore what will no longer exist!
  • by pb ( 1020 ) on Friday September 01, 2000 @09:05PM (#809856)
    I think I saw that movie...

    Good thing this is just Slashdot, so it isn't real or anything... :)
    ---
    pb Reply or e-mail; don't vaguely moderate [ncsu.edu].
  • by Minupla ( 62455 ) <`moc.liamg' `ta' `alpunim'> on Friday September 01, 2000 @10:45PM (#809859) Homepage Journal
    Agreed, I certinally wouldn't wanna underrate the job that the fine people at NEAT and the other tracking projects are doing, but all the same I do not think a few million mile away chunk of rock should be blown out of perportion.

    Y2K could have been a disaster too, but with (relitively) calm and proactive response by the IT industry it turned out to be a bust. This was wildly hailed by the media as "IT professionals yell wolf" after the fact. I'd rather not see the people from NEAT and others get tared with the same brush if there turns out that there are no asteroids on a colision course with our blue marble.

    Let's wait to find something that is going to hit us before we start panicing. Sure, go ahead, develop tracking and interception technologies, that's only prudent, but it's not front page news.
    ----
    Remove the rocks from my head to send email
  • I visited JPL [nasa.gov] a few summers ago and saw some of what the NEAT [nasa.gov] people were doing. They explained how the tic-tac-toe pictures [nasa.gov] on their page work. The basic idea is that a computer spends a few hours looking for blobs that look like they have moved linearly throughout the night, and then a person spends a few hours weeding out false positives and figuring out which asteroids are already known.

    Plug for the Summer Science Program [summerscience.org]: I was there in 1998 [summerscience.org], and I think it's quite a cool program. We (about 35 high school students) tracked known asteroids using a medium-sized telescope, developed photographic plates in a darkroom, and wrote C/C++ programs to determine the orbits of our asteroids based on the data we had collected. Oh yeah, and we visited JPL. Hint: go right before taking calculus and physics, so you can slack off for a semester when you get back to school :)

    --

  • I highly recommend Michio Kaku's "Hyperspace".

    Spacebob has a quick review of this book here [earthlink.net].

  • Actually the point of the theroy is that the odds are exactly the same. Its called the Gamblers Falicy. No matter how many times you roll a six on your die, the odds of you rolling the next six is exactly 1/6. The dice have no memory.

    What I was doing was atempting to establish odds for an event that I have only limited information on, (Although I do believe I read something sthat said that the odds of a substantial asteriod hit in the next 100 years is approx 1-in-10,000, which after you de-sensationalize it, translates into one substantial hit per 10,000 centuries, or one substantial hit in 1,000,000 years. That gives you the odds of an asteriod hitting you tommorow of 1 in 365,000,000. I'd buy a lottery ticket long before losing much sleep. Oh and stop driving *now* as your risk of dieing from that is astronomicly more likely. :)
    ----
    Remove the rocks from my head to send email
  • 8) Should people everywhere worry about being struck by a comet or asteroid? [nasa.gov]

    No one should worry about being struck, personally, by a comet or asteroid. The threat to an average person from disease, car accidents, accidents in the home, and from other natural disasters is much higher...

    --

  • by quux26 ( 27287 ) on Friday September 01, 2000 @11:18PM (#809868) Homepage
    "Consider how little a nudge it would take to make it hit us right on. I'm afraid I don't have the math for orbital mechanics, but my guess is that out by the apogee of its orbit it would take a very small angular change. How much force would it take? Are we talking about a small asteroid impact, a pass by a massive object warping its orbit, or what?"

    Think of it like a billiard ball. If the ball is going to miss the hole by just a little, a minor nudge will put it in. The closer it gets to the hole, the more of a nudge it will need to correct course. On the other hand the deflections doesn't need to be precise the closer it occurs to the pocket. But then add to that the complexity of three dimensions.

    So you'd have to have a very rare flyby of a significant object coupled with a very rare collision combined with some very unlucky and unlikely trajectory corrections that for all intent is random. I'm not holding my breath.

    But the question shouldn't be "how likely during my lifetime" but "how likely during the period of which we are not technilogically advanced (or willing) to evacuate." If you ask "how likely" as an open-timed question then the answer is "1".

    My .02
    Quux26

  • This really isn't a near anything... It's a huge miss.. Don't get paranoid...
    The only thing preventing rocks from pounding earth into dust is chance..
    Space is big... The Hitch Hikers guide to the galacy had it right....
    Earth is a really tiny target...

    Now to get worryed... that is ALL that protects us...
    That and we have NASA...
    (Hay Rob Limo want help your buddys at NASA when it comes to justifying NASAs budget? Tell em about near misses we keep having and how NASA may be all we have if we ever get something that is NOT a near miss.. we can nuke it if we know about it... thats were Nasa comes in)

    Ohhh maybe thats where the Mars landers went... they weren't landers.. they were bombs sent off to blow up asteroids heading into earth... We were never told..

    Anyway... don't get complacent... but don't get paranoid...
    Random chance is what keeps us from going splat...
    and that is like security by obscurity...
    It slows down.. it limits.. it dose not prevent...
    We are ok... relax...
    If a real rock comes... then break out the nukes...
    I'm thinking something like the bunker buster we develuped for the Golf War and a nuke... then we plow the missle into the heart of that larg rock and smash it to partical dust...
  • That's right, and it's like 93 million miles to the sun, so .037%
    comes out to around 2.9 million miles, or over 10 times the
    earth to the moon.

    Is that REALLY a close call?

    Steve
  • One of the most interesting things about this story is that the asteroid was only seen last weekend.

    If it had been on a collision course we wouldn't have had enough time to do anything about it.

    Asteroids on a true collision course don't appear to move in the sky; they just get larger. This makes them harder to detect than one which moves relative to the background of stars. An asteroid on a true collision course might not even be recognized as a threat until it was way too late to do anything. It is the punch you don't see that gets you.

  • by Anonymous Coward on Friday September 01, 2000 @09:10PM (#809883)
    (about half a km). And it is going by earth at about 0.0317 AU

    Our moon is 3476 km in diameter and is constantly 0.0026 AU from the Earth.

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