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Space Science

Assessing Asteroid Threat 202

Posted by Hemos from the learning-more-about-it dept.
Makarand writes "According to a proposal submitted to the European Space Agency a fleet of five mini-probes should be sent each targeting an asteroid considered potentially dangerous. The mission objective will be to learn more about dangerous near earth objects so that we can plan how best to respond when under threat. Once in space, the probes would use ion propulsion engines that provide thrust by shooting out a stream of electrically charged particles. Power for the ion engines would be provided by ultra-lightweight solar arrays. Each probe will carry instrumentation to learn about the physical and chemical make-up of the target. The mission would cost around $150 mil which is quite low according to space mission standards."
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Assessing Asteroid Threat More

Assessing Asteroid Threat

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  • Anyone else run into this problem? (Score:4, Funny)

    by HarveyBirdman ( 627248 ) on Monday February 17, 2003 @10:19AM (#5319255) Journal
    After watching the news or reading a paper, I find myself rooting for the asteroids.
    • Not to troll or anything, but frankly human beings have not interest in solving the problems of the world themselves. It always takes a disaster to knock some sense into us.

      If there was only a way technology could be used to solve big picture problems. Too often it solves the immediate needs at the expense of long term planning.

      • If there was only a way technology could be used to solve big picture problems. Too often it solves the immediate needs at the expense of long term planning.

        I think this is due more to human short-sightedness and greed than a problem with the technology itself.
      • Not to troll or anything, but frankly human beings have not interest in solving the problems of the world themselves. It always takes a disaster to knock some sense into us.

        Very true. Case in point: Saddam and Islamic terrorists before 9-11.

  • Armageddon (Score:2, Funny)

    by beaucfus ( 584676 )
    I am not worried, Bruce Willis will save us.

  • Awesome link (Score:2, Informative)

    by matt_fk ( 626813 )
    However, it is more like $160m.. not $150m in USD. 159,972,995.78 USD to be exact, as stated by http://www.xe.com/ucc.

  • hey! (Score:5, Funny)

    by Joe the Lesser ( 533425 ) on Monday February 17, 2003 @10:24AM (#5319287) Homepage Journal
    I thought I fixed this problem years ago with my Atari!

  • optimistic fools! (Score:5, Funny)

    by new death barbie ( 240326 ) on Monday February 17, 2003 @10:29AM (#5319316)
    Only an optimist wuld believe that the U.N would commit to a path of aggression, until all diplomatic options had been exhausted. The asteroids must be convinced to disarm themselves.
    • No, just let Mr. Laden say that muslims should strike back with terrorist attacks if the asteroids are harmed. According to Mr Powell that is enough evidence to send the entire US army to 'disarm' the asteroids.
      • No, just let Mr. Laden say that muslims should strike back with terrorist attacks if the asteroids are harmed. According to Mr Powell that is enough evidence to send the entire US army to 'disarm' the asteroids.

        Well, it is conceivable that al-Queda would resist attempts to deal with a dangerous meteorite heading towards Earth on the grounds that Allah sent it, or something.

  • Solution looking for a problem (Score:4, Funny)

    by Gothmolly ( 148874 ) on Monday February 17, 2003 @10:32AM (#5319332)
    Some VC has a Neat Idea, which nobody wants. Is that his fault, no! Who will buy it - Governments, they can print as much money as they need. Of course this was done in Europe, their monopoly-money machines work better than in the US (Russia has no money, monopoly or otherwise).

    Here's how you really get rid of an asteroid:
    Insert used ICBM into Space Shuttle (or equivalent)
    Place ICBM and suitable launch device into LOE.
    Aim ICBM at the place where the asteroid will be when it gets there.
    Press the button that we've wanted to push for so long. Sell tickets, I'm sure the Russians would want to attend - maybe a joint "button pushing" ceremony? Heck, bring the Chinese and N.Koreans in too.
    Watch as ICBM blows up asteroid.
    Profit!
    (Part where it ushers in a new sense of global peace and brotherhood is optional)

    • Re:Solution looking for a problem (Score:5, Insightful)

      by pe1rxq ( 141710 ) on Monday February 17, 2003 @10:39AM (#5319387) Homepage Journal
      Of course this was done in Europe, their monopoly-money machines work better than in the US (Russia has no money, monopoly or otherwise).

      You on the other hand have been watching to many american films... It is practicly impossible to do anything with an ICBM (or a whole bunch of them) against an asteroid.

      A new sense of global panic and anarchy is much more likely.....

      Jeroen

      • "You on the other hand have been watching to many american films... It is practicly impossible to do anything with an ICBM (or a whole bunch of them) against an asteroid."

        Use a series of them to nudge it out of the way, ala Project Orion.

      • Re:Solution looking for a problem (Score:5, Interesting)

        by jafac ( 1449 ) on Monday February 17, 2003 @02:35PM (#5320901) Homepage
        No, I think an ICBM would just about do the trick too, take off the warhead, and your payload becomes the third stage, get the third stage out of LEO using about half it's fuel (very rough assumption, expecially since we also would have had to fit it with appropriate guidance and maneuvering systems), land the 3rd stage ass-end-up on the asteroid, and fire the remaining fuel.

        ICBM doesn't necessarily mean "nuke".

        FYI - Mercury's Redstone, Gemini's Titan, etc. were formerly Ballistic Missiles - adapted for use in manned spaceflight - FYI.2; Titans are still one of the premier spacelauch vehicles in use today, and many are actual decomissioned ICBMs. (they're pretty useless as ICBMs compared to Minuteman or Peacekeeper, because Titans are liquid fueled) - but even so, I think a Peacekeeper would make an excellent asteroid-shover in a pinch, but I'm not sure exactly how much of the third stage would be left for asteroid-shoving if one just removed the warheads and fitted it with guidance/maneuver equipment. Maybe with some strap-ons?

        Now, we all KNOW that an ION engine would be better for this application, because you get your energy from solar radiation (or nuclear power), instead of burning your propellant and oxidizer, plus, you get to apply thrust over a much longer period of time, with much finer control. But on the other hand, we've had exactly ONE successful use of ION engines. It's a worthy wheel to reinvent, but that doesn't mean we shouldn't get something rolling more quickly than development of an ION-based asteroid-shover would take. Then do ION-based technology later. In any case, we definately have adequate technology to get such a device positioned. Much of it sitting unused, waiting around for armageddon. If an asteroid strikes our world and ends all life because we were saving our launch capability (idle ICBMs) for a massive nuclear strike, we'll even be jilted of that.
      • actually yet another very fine American Jerry Bruckheimer film called "Armageddon" would indeed teach you that throwing missiles to an asteroid wouldn't do shit. Instead you gotta send bruce willis after it, so he can dig a whole to its core, drop a nuke, and blow the thing into pieces. Jerrry Bruckheimer rules.
      • Insert used ICBM into Space Shuttle (or equivalent)

        Not only would an ICBM be tough to use, but a *USED* one would be even tougher.
    • Or more likely:

      Watch as ICBM blows up asteroid.
      Watch as world get bombarded by all the astroid's debris.
      Watch as instead of one continent/city (depending on size) gets destroyed, all world is obliterated.

      • no damnit. haven't you heard of the zero-barrier? it's that precise moment before which the thing needs to get blown up so the two pieces of the asteroid pass right by earth. Surely the movie Armageddon has it all figured out.
    • Sorry, forgot the
      <funny>
      tag, for the humor impaired.
    • Unfortunatly that won't work.

      An ICBM not even has the targeting capability to hit the asteroid.

      Neither does the war head has the precise enough timers to trigger in time(in case you like to ignition the war head on impact).

      Such an asteroid approaches the ICBM with a speed of about 10,000m/s. This is about 6 to 7 miles per second.

      If you trigger the war head on passing by, nothing happends at all, besides a heated surface, or probably a melted surface.

      Ok, so lets suppose you can approach the asteroid with a lander and plant the war head on the ground.

      Unfortuinatly that still wont work .... you need about 1000 war heads to alter the course significiant.

      Or you can dig some holes into the asteroid and plant the war heads inside. Exploding them, might break up the asteroid into parts.

      I for my part don't think that it is a big difference if one single piece hits north america(or europe, which is my side of the earth) or if 100s of parts are spread all over the northern hemisphere.

      Well, obviously its no difference also if one of those scenarios happens on the southern side :-)

      angel'o'sphere
      • "I for my part don't think that it is a big difference if one single piece hits north america(or europe, which is my side of the earth) or if 100s of parts are spread all over the northern hemisphere."

        Don't smaller pieces have bigger chance of burning away in the atmosphere?
      • Unfortuinatly that still wont work .... you need about 1000 war heads to alter the course significiant.

        However, due to the advancements in nuclear technology since the last great Hydrogen bomb was built in the 1960s (You know that 60 Megaton one that the soviets made), I'm sure we could slap together a device that could kick out in excess of 800-1000 megatons by now, hence just enough to do what you are suggesting.
        • However, due to the advancements in nuclear technology since the last great Hydrogen bomb was built in the 1960s (You know that 60 Megaton one that the soviets made), I'm sure we could slap together a device that could kick out in excess of 800-1000 megatons by now, hence just enough to do what you are suggesting.

          Slap together?

          The US has not been seeking ways to build bigger and bigger nukes, in spite of what some think here. Once we discovered we already had enough to make the planet uninhabitable (70s) then bigger was irrelevent.

          Because of the physics involved, its gets exponentially difficult to design bigger and bigger. Also, no way to test it on the planet. And no chance to make a 2nd one if the first one is a dud. Oh, and you are talking about a shitload of material to make that sucker. Even if you took all the material out of all the existing bombs to work with.

          Oh, one last point: Do you want them to build or launch that sucker in your hometown? I could see all kinds of no bath taking fuckers protesting all day and all night (after all, they don't have jobs to go to). I'm sure Nancy Pelosi would have a hayday attempting to get congress to block construction before an environmental impact study was done.

          (no pun on impact intended)
  • if they spot one heading for us the space elevator idea will suddenly seem extremely plausible

  • Spongy Asteroids (Score:5, Insightful)

    by Ella the Cat ( 133841 ) on Monday February 17, 2003 @10:35AM (#5319355) Homepage Journal

    Here in the UK there was a TV documentary (probably BBC2 Horizon, not sure) about asteroid impacts, how to deal with them and so on. I for one thought it was much like Arthur C Clarke's Hammer of God - find it early, deliver an impulse, deflect it a teeny weeny bit, and it misses by a few miles. Nope. The asteroid could be very porous, it just absorbs the blast, or requires an impossibly big bang to be sure it deflects. So sending probes to gather facts about asteroid composition is a good and useful practical thing over and above the scientific justification.

    • The asteroid could be very porous, it just absorbs the blast, or requires an impossibly big bang to be sure it deflects.

      Um sorry, but momentum is momentum. In space, the volume of the object doesn't really matter when you're trying to impart an impulse (as there's no air friction to worry about), it's just the mass. In that case, being porus would only help because it would mean that the mass is less than estimated. Any "absorption" wouldn't matter...

      Still a not a bad post.


  • That's no asteroid. It's a giant Space Potato [soupyet.com]!

  • I see what they're trying to do, but so what if we do detect an asteroid the size of Texas headed straight at us ? (Armageddon or Deep Impact, anyone?)

    I doubt that there will be anything significant that we will be able to do except predict the end of the world, and you bet that I'll be quitting my job then! :)

    • There must be some range of size that is too big to ignore and small enough to do something about. So why not?
    • Its not pointless at all.

      There are plenty of ways to alter the course of an asteroid.

      E.g. if there are gases, or frozen liquids on such a thing you could try to use a steam rocket.

      Solar power heats the stuff up and uses the gases like in a rocket engine.

      You could try to alter the albedo/colour by painting the surface. There was a /. article about that idea bout 6 monthes ago.

      Far more interesting is the attempt to put solar sails on it, to drag it away, however such a asteroid will be rotating somehow. Rotation would be needed to stop, or a way needs to be found to tackle a rotating asteroid.

      Lasers could be used, not like in Star Wars but as constant pressure, instead of solar sails, to push it away(of course we would need a laser on the moon for that or in space).

      I could imagine there are hundrets of concepts thinkable but ony a few will suit a specific asteroid.

      Also: not only asteroids are a problem, comets as well. But those are more rare and more easy to spot :-) However they are that fragile that they will be realy hard to get rid of them. A steam rocket might be suitable but also it might just not stick on the body because of the fragility.

      So a giant net, wrapped around the asteroid might be usefull ... to attach solar sails or steam rockets on it.

      How to manufactor them, probably with resources on the body itself ...

      Pleanty of questions. Plenty of reason to go and look.

      angel'o'sphere
    • detect an asteroid the size of Texas headed straight at us?

      Just for the record, Texas is 266,807 sq miles [kidport.com]. Does it make sense to compare a two dimensional item like a state to a three dimensional object like an asteroid? How? Compare the surface area of the asteroid to Texas? 4 pi r^2 is the formula for the area of a sphere.

      Maybe one should use the largest cross section? This site says Vesta [solarviews.com], the third largest asteroid, is the size of the state of Arizona. This site [enchantedlearning.com] and this site [solarviews.com] list some of the larger asteroids.

      Let me suggest that the chance of Ceres sneaking up on us is not one in a billion, or one in a trillion. Let me suggest it is zero.

      Are there any asteroids the size of US states that haven't been discovered yet? None with Earth crossing orbits.

      Are Kuiper Belt Objects asteroids? If so Ceres is no longer the largest asteroid. [planetary.org]. But it is even more unlikely that something would divert a Ceres size KBO from past the orbit of Pluto to Earth orbit.

      How long would it take to divert an asteroid from an Earth impact? Decades? Centuries? Millenia? Anyhow, Deep Impact had the incoming object be a comet. Even with a project to find deadly NEOs, we could still be snuck up on by a long period or extra-solar comet.

  • Ok, so these are asteroids percieved to be dangerous, as in "may hit us at some point". If they do hit us, what the heck is knowledge of their chemical composition going to achieve in terms of post-impact help? This does not make sense to me...

    ----rhad

    • Composition matters (Score:3, Insightful)

      by Firethorn ( 177587 )
      For several reasons. The primary, of course, is so we know what methods will work best for moving the asteroid's orbit enough so it doesn't hit. Secondly, knowing it's composition will allow us to better estimate it's effect. A mostly silicon (sand-ball) asteroid will have different impact characteristics than a lead/iron 'bullet'.

  • In other news ... (Score:3, Funny)

    by Xthlc ( 20317 ) on Monday February 17, 2003 @10:40AM (#5319390)
    ...NASA proposes a $300 million project to build a gigantic "Welcome to Earth! We value our children, please abduct safely!" sign on the moon. This is to remind alien vacationers (who come speedin' down that local group highway like nobody's business) to slow down a spell, and think carefully before they start carrying off our kids and probing them.

    Seriously, does anyone else think this is a waste of resources? Give that $150 million to Highlift [slashdot.org] for Pete's sake...

  • cold war leftover (Score:3, Insightful)

    by oliverthered ( 187439 ) <oliverthered@hot[ ]l.com ['mai' in gap]> on Monday February 17, 2003 @10:40AM (#5319393) Journal
    Seriously, when did you first hear about dirty bombs and Asteroids that would kill us all?
    Shortly after the 'end?' of the cold war.

    All that got swept under the carpet when the axis of evil decended upon the earth(though the dirty bomb's popped it's head up again).


    • Seriously, when did you first hear about dirty bombs and Asteroids that would kill us all?
      Shortly after the 'end?' of the cold war.

      All that got swept under the carpet when the axis of evil decended upon the earth(though the dirty bomb's popped it's head up again).

      Well,

      I'm 36 ... erm, shit. 37 now.

      I know it snce I can think back, so probably since the age of 10.

      No idea how long you know it, probably you are just to young? Or to ignorant? I mean: you still try to say, you do not know it, even more: you think its an invention, right?

      angel'o'sphere
    • It's just a matter of priorities. A dirty bomb or hijacked airliner will kill a few thousand at most. With the Cold War we faced the prospect of a few nukes on every major city at once. Directly comparing the terrorists to the cold war lacks any sense of proportion.

  • A gamble for 10 billion... (Score:4, Interesting)

    by little1973 ( 467075 ) on Monday February 17, 2003 @10:41AM (#5319398)
    That is the raw translation of a hungarian novel written in the early 80's.

    It takes place in the near future when the Earth population is 10 billion. An asteroid threatens Earth, but so big nothing can be done just one thing. By calculating the trajectory of the asteriod the engineers notice that it nearly collide another, but smaller asteroid.

    So, they send up a spaceship with full of explosives and ram it into the small asteroid in order to give it a push which is sufficient to make it collide with the big one.

    Billiard on the cosmic scale. And it was written well before the public became aware of the asteriod threat.

  • Different types of object? (Score:5, Funny)

    by spakka ( 606417 ) on Monday February 17, 2003 @10:43AM (#5319412)

    Each Simone spacecraft will have instruments designed to examine the physical and chemical make-up of its target asteroid. It is hoped the missions will help scientists predict the risk posed by asteroids and develop effective strategies for dealing with different types of object.

    What properties, other than mass and trajectory, are of interest? It's not like they're going to find harmless ones made out of rubber or whatever.

    • Density, composition, anything likely to affect our ability to change its path by pushing it, attempting to break it up into smaller pieces that would either miss the Earth or burn up during entry...

      Knowing whether these asteroids are ice, rock, hollow, loose clumps of small pieces held together by gravity, all of this is important.

      Not all of physics can be modeled by assuming everything is a sphere with mass and velocity.

    • What properties? (Score:3, Insightful)

      by dpilot ( 134227 )
      Principally, how physically strong is the object.

      If it's strong enough, perhaps like a nickel-iron object, perhaps the best way to deflect it is with explosives.

      If it's weak enough, perhaps explosives could blast it to smithereens, all small enough to burn up in the atmosphere. This would also indicate that it's time to get together and work up an exception to the "no nukes in space" treaty.

      If it's somewhere in between, then it's time to ship some sort of rocket engine up there to move it. In that case we have to question just how much thrust it can structurally take before it breaks into pieces, leaving our engine shooting off into nowhere.
      • perhaps explosives could blast it to smithereens, all small enough to burn up in the atmosphere?

        IANA physicist, but it seems to me that the parent contribution here, like many contributions in this thread, seriously underestimates the magnitude of the forces we are talking about.

        Would the fragments of a demolished asteroid burning up in the atmosphere be significantly less disruptive than having the intact asteroid smash into the Earth? What were the global effects of the dinosaur killer?

        It threw up huge amounts of dust? If fragments of the asteroid "burn up in the Earth's atmosphere" will that produce a worse dust problem or a better dust problem than if one big asteroid strikes the surface?

        Heat radiation ignited continent wide firestorms? Would a rain of billions of tons of meteors burning up in the atmosphere ignite a firestorm? The Tunguska object ( if it existed [zetatalk.com]) was something like 50 to 80 meters in diameter. If I have done my math right, it would have massed something like half a million to a couple of million tons. The dinosaur killer was supposed to be something like 10 to 20 km in diameter, I believe. That would be 10 to 100 trillion tons.

        Kinetic energy is, IIRC, one half mass x velocity squared. Earth's escape velocity is 11 kilometres per second. Suppose that was Tunguska's initial velocity? IANA Physicist, but wouldn't a one kilogram meteor, at 11,000 meters per second, surrender 60,500,000,000,000 Joules? 1.5*10^12 calories? It takes something like 660,000,000 calories to boil a cubic metre of water. And so your one kilogram meteor could boil 23,000 cubic metres of water. If I have done my arithmetic right, Tunguska could have boiled something like several tens of thousands of cubic metres of water. And, the dinosaur killer could have boiled at least 10^17 cubic metres of water. The Earth's atmosphere currently contains 1,290 cubic kilometres of water [nasa.gov]. A dinosaur killer, that burned up, and surrendered all its energy in the atmosphere, would release enough heat to raise the amount of water vapour in the atmosphere one thousand fold.

        Maybe the Earth would be better off if the next dinosaur killer stayed in one piece, and spent some of its energy busting rock?

      • This would also indicate that it's time to get together and work up an exception to the "no nukes in space" treaty.

        There are several treaties that would proscribe a single nation from militarizing space with nuclear weapons. One is the 1972 Anti-ballistic missile treaty. George W. Bush has already announced that the USA will no longer abide by this treaty.

        But I don't believe any one of those treaties would proscribe a truly international effort.

      • ...then it's time to ship some sort of rocket engine up there to move it. In that case we have to question just how much thrust it can structurally take before it breaks into pieces, leaving our engine shooting off into nowhere.

        Woops. Consider that the Saturn V could deliver just 49 tons to the Moon's orbit.

        The Tunguska object, would have massed more than 500,000 tons -- maybe 5,000,000 tons. The asteroid Apollo, 1.6km in diameter, masses 20 billion tons -- 20,000,000,000 tons [enchantedlearning.com]. How much power do we need to divert it?

        The bottom stage of the Saturn V generates something like 160,000 horsepower, for something like 160 seconds. That is, if my arithmetic is right, something like 10^12 joules. Of course we couldn't get an intact Saturn V delivered to an approaching asteroid -- not with chemical rockets. The Saturn V could only deposit 50 tons to the Moon's orbit. But suppose we could? If the asteroid Apollo was going to impact right in the centre of Earth how far in advance would we have to light the candle of this theoretical Saturn V to divert the asteroid enough to miss us?

        Kinetic energy == mass * velocity squared / 2

        10^12 joules transmitted to 2*10^13 kilograms? If my Physics is not too rusty, will impart a velocity of one twentieth of a meter per second. Five centimetres a second? That is 0.18 km / hour.

        At that rate you would have to light the candle on that theoretical Saturn V at least four years before impact to prevent the collision.

        To be really safe, because tidal forces would rip the asteroid apart prior to impact. Tidal forces ripped Shoemaker-Levy 9 into fragments. So you would be better served lighting the candle decades in advance.

        Now, consider how big a payload could we deliver to a comet or asteroid years or decades in advance? Miniscule.

        So, what about using atomic charges? Asteroids might be as fragile as piles of rubble. A single charge might shatter the asteroid, leaving an uncontrollable cloud, still aimed at us like buckshot from a giant shotgun.

        Would it matter if the asteroid shattered, if we didn't use one charge, but rather dozens, or hundreds, designed to explode more or less simultaneously? In the sixties there was lipservice paid to using atomic charges for peaceful demolition work here on Earth. The best known plan was to blast a 2nd, sea-level, Panama canal. One of the odd things you learned if you read about this was that if the charges all exploded at once you would get a trench with remarkably straight, even walls.

        Or, consider how a shaped charge anti-tank warhead works. The charge is turned into a kind of lense of explosive. The business end has a conical hole carved in it. That cone is coated by a thin layer of copper. When the warhead explodes, the explosion travels through the explosive. When it gets to the apex of the conical hole it begins to focus the metal into a jet. I came across some really cool slow motion pictures of this process -- can't find them now though.

        So, what if we landed a network of charges over one hemisphere of the asteroid, and had them go off in a rapid sequence? Could the expanding concussions redirect rubble away from the Earth, leaving a small amount of very rapidly moving small particles going east, and the rest of the asteroid going west, with essentially none coming right at us? If the asteroid shatters, would the overlapping concussions focus the bulk of the rubble in a single direction? Would charges spread all over the surface of one hemisphere help preserve the structural integrity of asteroid in a way a single charge wouldn't?

    • What properties, other than mass and trajectory, are of interest? It's not like they're going to find harmless ones made out of rubber or whatever.

      How about "How easy it is to push into a different orbit that misses the Earth?" I don't know about you, but that's a property that I'm very interested in, and it'd be silly to think that all asteroids are the same...

    • What properties, other than mass and trajectory, are of interest? It's not like they're going to find harmless ones made out of rubber or whatever.

      An asteroid made of a nice brittle material could be shattered - a softer or more porous material would have to be deflected. One that's mostly water could be dealt with slowly by focussing sunlight onto it over a period of years, so evaporation alters its trajectory. One that's mostly basalt or iron would require a different strategy.

  • Simon says (Score:5, Funny)

    by QEDog ( 610238 ) on Monday February 17, 2003 @10:45AM (#5319423)
    "The asteroid mission has been named Simone (Smallsat Intercept Missions to Objects Near Earth)."

    Pretty smart using Simon to stop the asteroid... "Simon says jump on one foot. Simon says don't hit the Earth..."

    Next on /. how to save Earth from an Alien attack using the Hockey-Pockey

  • so what they're telling us (Score:1, Funny)

    by Anonymous Coward
    IMO, is that an asteroid that's on a collision course for Earth has been detected and they're leaking it in various ways to news reporters.
  • not from the heavens, but from the human beings on the planet.

    Why do we worry about these thing when the population of this planet can't even figure out how to deal with the threats on this planet that we have control over?
  • Deep Space 1 (DS1) was the first probe to use ion propulsion. There were 12 other advanced technology used on that probe. You can find more here [nasa.gov].

  • what characteristics? (Score:4, Interesting)

    by fermion ( 181285 ) on Monday February 17, 2003 @10:56AM (#5319485) Homepage Journal
    The article is quite short on details of exactly what threat characteristics we are to catalog. My understanding is that the two most important characteristics that threaten us is that the object has mass and will likely collide with earth. Both of these can be estimated quite well in enough without a mission to the object. Any characteristics beyond that, be it shape or chemical composition, does not seem to be so critical.

    Now, one might argue that if we knew things like chemical make up or density or the like we might know how to destroy the object or perhaps could change it's trajectory with engines or a tractor beam or something. However, this implies that we know the object exists with enough advance notice to do something. To plan a research encounter, that might be a year. To plan a destructive encounter, I think that might be a month. I seem to remember that the in the last near miss, we did not detect the object until after it had passed.

    Which is to say that we need better detection technology coupled with serious research of how to change trajectory. I do not believe converting a single projectile into hundred of projectiles is a reasonable solution. And of course, if we don't know the object is coming, there is nothing we can do

  • then what? (Score:1, Redundant)

    by Xpilot ( 117961 )
    After we identify a dangerous asteroid... we send Bruce Willis up to nuke it?
  • Instead of changing the orbit of the asteroid, why not simply change the orbit of the earth. All that is needed is the entire Chinese population jumping. Once we have safely avoided the asteroid, someone on the other side of the earth can nudge it back in place with some additional jumping, we might even improve the orbit a tad while we're at it. Obviously this is cheaper, more enviroment friendly and whole lot more "down to earth" than the proposed ICBM plans.
    • Trouble is, they come back down again, negating the effect. Better to get some large population to all face the same way, then fart. Muslims would be ideal. Issue them with cigarette lighters for a larger deflection.
      • Wouldn't that just change the rotation? They would all have to be pointing up or something.

        Trouble is, they come back down again, negating the effect.

        I still think the jumping option is promising. If the whole population of china jumps up onto chairs, waits for the asteroid to slip by the planet, and then jumps down again, then we are set.
  • So everyone is making jokes about the topic, but wasn't there this story about this asteroid that would get close to earth somewhere in 2016 or so (can't remember the year), and that would raise the temperature of the earth to 50 degrees celsius at the moment it passes by? Or was that story declared invalid later on?

  • We spent more money... (Score:3, Insightful)

    by EvilTwinSkippy ( 112490 ) <yoda@e[ ]oc.com ['toy' in gap]> on Monday February 17, 2003 @11:27AM (#5319700) Homepage Journal
    Seeing if ants will tunnel inside of a test tube in space. (Not to mention 7 lives.)

    $150 million to explore the REAL dangers of space is cheap at twice the price.

  • While this research may well give us some miscellaneous bonus research regarding asteroids and such, it seems slightly fruitless.

    Yes, there is a chance an asteroid will hit us. There's also a chance black hole will spring up next to us and suck us in. There's even a tiny chance that the sun will extinguish itself leaving us with the task of trying to reignite it.

    Why waste money on such research which will, inevitably, be pretty useless when (and if) an asteroid the size of Britain comes along our way.

    I think these guys have finally got around to renting Armaggedon and got a little paranoid.
    • Well, so far, no black holes have appeared right next to the planet and sucked it in, or, well, we wouldn't be having this conversation. OTOH, asteroids do hit the earth, and not all that infrequently, geologically speaking.

      You're right, there's not a damn thing we could do about an asteroid the size of Britain; that would be a planet-killer, and we couldn't stop it. Something along the lines of the dinosaur-killer, though? (Estimated at a few kilometers in diameter, IIRC.) That we might be able to do something about ... if we knew enough about it, and had enough advance warning. The spacefaring nations of the world could come up with some pretty impressive rock-stopping technology pretty fast with that kind of motivation. Ingorance in this case is definitely not bliss.

      You're putting the cart before the horse in mentioning Armageddon. The reason that movie was made is that someone in Hollywood finally noticed what scientists and SF authors have been talking about for years. If you honestly think that scientists got their ideas on asteroid impacts from Hollywood, you haven't been paying attention.
    • I think these guys have finally got around to renting Armaggedon

      No, I think you (and whoever up-modded you) fill entirely too much of your brain with bad sci-fi.

      The chance of a black hole suddenly popping up and sucking in the earth is around 10^-100. The chance of the sun extinguishing or exploding sooner than 2 billion years from now is comparable. This is based on both theoretical calculation (simple astrophysics) and physical observation (never seen).

      On the other hand, the odds of a killer asteroid impact within our lifetime is is 10^-6 or higher. We have seen impacts firsthand [stsci.edu] (note that the blast shown here [stsci.edu] is the same size as Earth), and we know the likely results [google.com].

      Last, between chemical rocketry, ion engines, and good old H-bombs, we have technology to do something about a future impact, given sufficient lead time. Summary: don't be a dork, russx2.
  • to make fuel and infrastructure from materials already in space [permanent.com]

    I hope to see that happen in my lifetime - even if permanent.com is too optimistic. That's why I like these probes, not because of the (negligible) impact danger.
  • Once in space, the probes would use ion propulsion engines that provide thrust by shooting out a stream of electrically charged particles. Power for the ion engines would be provided by ultra-lightweight solar arrays.

    Hmmmm....so, a pair of flat, lightweight solar arrays. I betcha you'd have to mount the ion engines in parallel, to keep the thing from spinning uncontrollably. And a center sensor/instrumentation package...

    Why does this sound familiar? [rpgplanet.com]

  • A lot of negativism (Score:5, Interesting)

    by panurge ( 573432 ) on Monday February 17, 2003 @11:54AM (#5319895)
    A lot of the arguments so far seem to be of the "why give up smoking, I might fall under a bus" variety. From the same people that continue to buy SUVs?

    Considering the amount of money spent on practising for war every year - "defense", the proposal to the EU is peanuts. It is a proposal to start investigating the possibilities of a very real threat. I seem to recall the Siberian meteor impact as estimated as equivalent to about a 30MT H-bomb, and we were very lucky it hit where it did. It also seems that satellite photography is identifying more and more impact sites on the Earth. When I was a kid very few of these were recognised, and it seems reasonable to me that if we are learning that the frequency of such hits is much higher than expected, we should start to do something.
    It's also worth remembering that the big impact on Jupiter occurred only a few years ago, and that very visible impact may well have concentrated people's minds. As telescopes get better, astronomers are realising there is far more debris out there than anybody knew- the old idea of 9 tidy planets and an asteroid belt has turned into a solar system full of all kinds of junk, moonlets, comet formation belts- the Solar System seems to be more like Mexico City than Singapore, if you see what I mean.
    A billion dollars sound like a lot, but how much is the ABM system going to cost?

    Dealing with a hard rock or a dirty snowball could need very different approaches (gentle push versus big bang?). Just because a multi-mile wide asteroid could be undeflectable and fatal, doesn;t mean that the real threat might come from a thing 100M across - obviously deflectable with the right technology, but nuking it could result in thousands of destructive small impacts.

    To sum up this ramble:

    • Destructive meteor impacts do occur on Earth
    • Some of them are potentially preventable
    • The cost of research is probably going to be far less than the US is going to spend developing nuclear warheads this year
    • The cost of stopping a small asteroid could be a lot less than the estimated budget for stopping Saddam Hussein
    • All in all, it looks far from a waste of EU money.
    Thank you for reading this far.
    • Yep, this is true, although you have to admit we would be horrendusly unlucky if a fatal asteroid did hit us anytime soon.

      Think about it, the dinosaurs had how many million years to develop ways to prevent a fatal disaster? And they didn't have the intelligence too. Intelligent humans have only been around 4/5000 years, and we've already come *incredibly* far. All we need is another 5000, and I predict we'll have moved off Earth and colonized hundreds of other plantets, as well as building permenant space stations, providing there is no fatal disaster. It would be a rather tragic end to humankind if, after only a very small period of time in evolutionary terms, we were wiped out. We should at least be given another million years :-)
  • We already know that there are a lot of objects in space which are powerful enough to cause a 10 megaton explosion but which we will not be able to see until they enter the atmosphere. Now, back in 1908 when one hit us, it hit us in a remote area so not many people in the world knew about (except, of course, those unfortunate people who where within a couple tens of miles of it when it struck.) But nowadays, EVERYONE would IMMEDIATELY know that an explosion as powerful as a nuclear weapon had just gone off in their back yard, and there's a good chance that they would immediately retaliate against whoever they thought launched it.

    Wouldn't it be ironic if we helped an incoming asteroid finish us off, rather than hindering it?

  • Ion Engines Not New (Score:3, Interesting)

    by beaverfever ( 584714 ) on Monday February 17, 2003 @12:36PM (#5320149) Homepage
    I found a website here [starwars.com] which has specifications for a space vehicle with dual ion engines and solar arrays to power them. This one is manned, too.
  • ESA was talking about this project (and five other) in September of last year.

    See this [esa.int] link for a little information on them all, and some background gumf.

  • "The mission objective will be to learn more about dangerous near earth objects so that we can plan how best to respond when under threat." ...can a near earth object really do harm to us? I mean really? Shouldn't it be quite obvious that they're going to smash into earth, boiling seas, causing tremendous tsunamis, earthquakes the likes of which have never been seen and never again will be seen by humans? Let me guess, the French proposed this "diplomatic" solution to try to talk the asteroids out of smashing into Earth. I'd rather see that $150 million invested into ways to destroy an asteroid before it becomes a serious threat.
  • It's not really based on hard evidence except what I've seen of meteorites in museums. Basically I think that when these probes are sent they'll find that asteroids are in fact made of rock.
  • There was a recent article about a similar sized probe, designed solely to inspect satellites for external damage. It will cost $60 millkion a pop. So I am highly skeptical that these probes, which will include a brand new ion engine, will cost just $30 million.
  • You can't deflect a meteor much by crashing NASA probes into it. I suppose that's why they're looking at it in Europe.
  • Once a threat is identified, it makes no sense to blow it up into pieces because the pieces still would have nearly as devastating effect on the earth as the original monolithic object. That leaves what is probably the best solution: change it's orbit by moving it. How to do that? Build nuclear blast proof parabolic dishes or excavate a parabolic shape on the menacing asteroid's surface and place a nuclear device at the focus and detonate it. The thrust from the blast will deflect the object from hitting Earth. Experimentation, research and computer modeling will need to be done before the efficacy of such an approach can be assessed, and as always, the more lead-time you have in identifying the threat, the better!

    BTM
  • to settle a long standing argument. When we are sure an asteroid is going to hit us we will attempt to stop it using only means that are not the result of weapons developement. That way we'll know for sure if all the hippies were right about war not doing anyone any good.

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