Nuclear weapons could be used to stop earth-bound asteroids, but in most instances, they are not the best option, said Apollo astronaut Rusty Schweickart during a public lecture this Wednesday in San Francisco.
The venerable scientist explained that all but the largest heavenly bodies can be redirected by rear-ending or towing them with an unmanned spacecraft. But last year, NASA issued a report stating that using nukes is the best strategy to prevent a catastrophic collision with earth.
Although Schweickart has a great deal of faith in the agency, enough to risk his life piloting their lunar lander, he feels that they issued the misleading statement -- under immense political pressure. It was a nefarious excuse to put nuclear weapons in space.
His own organization, the B612 Foundation, intends to use gentler tactics to alter the course of an asteroid by 2015.
Right now, humans are not tracking most of the objects that could cause serious damage to earth, but in the next century, as powerful new telescopes come online, we will begin watching many of them. When that day comes, we will know which ones stand a chance of hitting earth, and it will be time to make some tough decisions.
Since tracking asteroids contains an element of uncertainty, there will be a lot of false alarms, so it may not be necessary to take action at all. If it must be stopped, should we bump it, drag it, or blow it off course?
The astronaut compares our current situation to standing blindfolded in a batting cage. Right now, we can't do anything, but we know that some balls are hurling towards us. In a few years, our blindfold will come off, and the whole world will be forced to decide -- together -- when to duck.
See Also:
- Virgin Galactic Unveils Launch Plane for Upcoming Spacecraft
- Gallery: NASA's Most Amazing Extraterrestrial Vehicles
- First Look at Virgin Galactic's New Mothership, WhiteKnightTwo
- Exclusive Video: Meet the Spacecraft That Could Save NASA a Fortune
Image: Don Davis / NASA Photo: Jessica Culler
Posted by: George M. Bonnett | Jul 27, 2008 4:19:32 PM
You don't want to destroy or deflect comets or asteroids, you want to capture and harvest them. How much do we pay to launch a pound into space? It's time to think recycle and refine in space. The first real presence in space will be defined by our ability to use native materials.
When that day comes, space exploration will be profit based and the universe will open up to humanity.
Posted by: cyberbian | Jul 27, 2008 4:35:33 PM
I see a whole new series of Hollywood movies here. Just send the towing guys up there. Heck Billy Bob and Big Duke can pull it out of the way - nothing to it. Then Oops!... and hilarity ensues.
Posted by: George | Jul 27, 2008 4:41:37 PM
I am not sure how well a nuclear explosion would work at nudging something when there is no atmospheric medium such as air. Usually a nuclear explosion in outer space(vacuum) creates mainly x-rays. At the end of the day, nudging is a momentum problem (mass*velocity). So you either have to put a lot of mass in space or something less massive with a lot of velocity. A smart thing to do would be to calculate how much mass at what velocity would need to be "chipped" off the asteroid to deviate its trajectory.
Posted by: Bob | Jul 27, 2008 4:50:06 PM
The radiation from the nuclear blast would vaporize some of the asteroid and send it flying away from the main body, creating a sort of ad-hoc rocket effect.
Posted by: AaronRowe | Jul 27, 2008 4:52:01 PM
As has been said the strategy of using of nukes is to nudge them of course well in advance using multiple detonations relatively near to the target object.
I doubt an unmanned craft would be nearly as effective.
Also for the real last minute emergencies we should have a plan to use a large mass near to the earth to collide with an incoming object (we should be ready to sever off a fairly large mass of moon rock)
Posted by: | Jul 27, 2008 4:52:20 PM
when the time comes some of us will be ready
Posted by: brianly | Jul 27, 2008 4:55:53 PM
Got Bruce Willis?
Posted by: Smiddi | Jul 27, 2008 5:08:03 PM
If a big asteroid were to hit the earth, I'd just laugh.
Posted by: Matt | Jul 27, 2008 5:09:27 PM
way to go NASA....soooo many things can go wrong I can't even start
Posted by: | Jul 27, 2008 5:17:59 PM
So many of these coments fail so hard.
Posted by: Holy Steve Buscemi, Batman. | Jul 27, 2008 5:26:13 PM
If we were to use a nuclear weapon against an asteroid, there would be a few problems-
1.The asteroid might break apart into several smaller pieces, possibly making the problem worse
2.The size of the nuclear warhead would have to be enormous in order to blast a huge rock out of the way. Blowing up a huge nuclear warhead would create alot of radiation, and some of it will come back down to Earth.
I think the best way to deal with an asteroid is to send a rocket to the asteroid, land on the rock and use that rocket to push the asteroid out of the way. It would be a real pain, but we have landed spacecraft on an asteroid before.
And if that fails... NUKE IT!
Posted by: bigplrbear | Jul 27, 2008 5:38:45 PM
Let's try to put this in perspective:
Look at the Tunguska event 100 years ago. Anyone have any idea how much the earth has been disrupted from it's "original" orbit/trajectory from that event?
Like the SF writers of yore knew: Resistance is Futile
Posted by: mike | Jul 27, 2008 5:39:02 PM
I think this says it all:
http://youtube.com/watch?v=1-ReuLZ2quc
Neil Degrasse Tyson is one of the leading astrophysicists in the world and here's his take on how to defect an asteroid, in this case Apophis.
Posted by: Doug S. | Jul 27, 2008 5:56:03 PM
Can't we just fly up to the asteroid with a rag-tag team of the world's best oil drillers, land on the asteroid, drill a few thousand meters to its core, and drop the nuke inside of it? Also, Steven Tyler. This ride needs a killer soundtrack.
Posted by: Jon B | Jul 27, 2008 6:08:01 PM
The way the world is going, it might be destroyed hundred years before the next asteroid comes.
Posted by: Ninad | Jul 27, 2008 6:08:18 PM
How is it that all of you commentors completely missed the point of this article?
"It was a nefarious excuse to put nuclear weapons in space."
You're all excited about how to re-direct an asteroid but not at all concerned that the gov't is taking a strong-armed hold on space?
If we're going to be concerned about our apocalypse, why not start with examining all the people preparing to kick it off?
It'll be a nuke space race. The Really Cold War.
Posted by: eric | Jul 27, 2008 6:51:03 PM
If a threat were detected early enough, we could deploy a solar parachute and let the solar wind do the work.
Nukes would likely be a last-shot solution.
Posted by: Martin | Jul 27, 2008 7:02:39 PM
And if the rocket that carries the nuke fails - i will just laugh so hard.
no matter what, the government does what they want to do. So stop pointing out things and enjoy the show.
Posted by: hahahah | Jul 27, 2008 7:26:09 PM
I'm not worried about the asteroid breaking up into big pieces--just nuke the pieces. Nuclear missiles are cheap compared with other solutions so we can have spares. What does worry me is the thought that the first explosion will throw off bits of dust &c that will be lethal obstacles for subsequent rounds. Has anyone looked into this? The bomb has to get within about fifty to a hundred metres or so, IIRC, which is a difficult guidance problem.
Posted by: David Bofinger | Jul 27, 2008 7:38:21 PM
As of right now... he is wrong. There are no spaceships or anything of large enough mass to tow or bump an asteroid.
I suppose mining the moon for mass to hurl against the incoming asteroid is a possibility.
Perhaps we should just tow a solid iron asteroid into earth orbit and attach thrusters to it to have something to actually hurl at it.
Really, though, how you take out an asteroid depends on the composition of the thing. Some are just balls of dust, some are a solid chunk.
I think a bunker busting style nuke makes the most sense. You want something that will have a controlled blast not like a standard nuclear explosion which detonated above the surface.
I think basically a stream of these asteroid busters could basically chisel through just about any asteroid. AND it's technology that really exists. You might need a few thousand to take out something huge, but the best way to look at it is .. what's the lightest fuel we can lift into space that has the highest energy density or power density.
You could certainly make a tow ship or array of tow ships, but you have to attack an anchor or such which is going to be difficult since asteroids vary in solidity.
Plus, more importantly, what magic fuel will you use to generate that much force ? AND how will you get the tow ships to the asteroid in time to slowly move it off course ?
Nuclear is just the most power density we have, and it's the only even mildly realistic idea.
You basically make a serious of guided nuclear powered drills.
The idea that the asteroid will be more dangerous in many smaller pieces is simply wrong.
At the very least more surface area means more friction, which means less inertia upon impact.
However, hitting a collection of fly debris from millions of miles away is going to spread the debris over a large area. Since most asteroids are not solid and their mass is not that great, nuclear blasts will in fact spread them apart advantageously unless only done at the last second.
In which case enough volleys will produce enough force to move it or bore through it or whatever you have to do.
It's like the shuttle vs the launch vehicle on a missile. You want to make a small, mass produced nuke warhead that fits the payload capacity of your most mass producible missile. This way you hit the sweet spot and you cost effectively put the most fuel into space in the form of nuclear warheads.
It doesn't HAVE to be a simple nuclear warhead, but most likely the fuel we would use is nuclear and most likely in the form of a cluster warhead or just a stream of missiles.
There really isn't a lot of other real options beside as I said getting out own pet asteroid and mounting thrusters on it to control it's course and slingshot it into any incoming asteroids. I think, it's an odd one, but it's practical and within our technological limits.
Other ideas like... sending a floating mirror out there.. at least the efficiently battle the lack of energy problem by using solar power, but I don't see them actually achieving the goal of moving a variety of different asteroid types.
No all asteroids have ice pockets and how much thrust does heating ice pockets really make.
Nope... nuclear bunker busters redesigned into asteroid busters is likely the best we can do.
Instead of betting on the technology to deflect asteroids ranging in size from half a mile to 120 miles or even more. We should prepare for disaster... we should have an underground city, that functions like any other city today but is ready to preserve technology and American culture in case of a global disaster, which is BOUND to happen.
It could just be a continental land or ice shelf breaking off causing hundred foot tidal waves. It could be a gamma burst that roasts the ozone and radiates the surface. There are lots of things that could just end our way of life and erase most of the progress humanity has made.
Instead of some dumbass moon or Mars base, an underground city running on geothermal with industry and people, not just some tiny bunker that sits there and wastes money and will likely be forgotten when it's time to use it.
Imagine the national security of being the ONLY nation prepared for these extinction level events. America would pop back up 10 times faster than nations who did not prepare for potentially several years underground or longer.
We should be ready, being underground is the edge the mammals had that left the world to them after the last major extinction.
Little moles took over the planet and now they think they can tow asteroids.. cmon. Tow something 3 miles wide... with merely what you can launch into space. We'd probably spend 100 years lifting that much fuel into space and assembling a huge tow ship.
It's a waste because we simply don't have that type of technology at all, the energy levels just don't exist without nuclear explosions.
So either produce a nuclear engine that produces tons of thrust efficiently or you'll have to resort to the energy release of fission.
I don't think without slingshots we have the type of fuel and engines we need to move objects of that size even over a long time. The prospects of getting that much fuel and technology millions of years out to earth and having it all work.. is pretty slim.
On the other hand.. I bet we could manage to design guided/autonomous missiles to hit moving targets through space. NASA managed to hit a comet, so the technology is likely ready though we don't spend much time on nuclear research anymore.
The scary part, of course, is getting all those nukes into space.
What we need for now is better tracking and a little bit of luck that the big one doesn't come.
Posted by: Matt Everett | Jul 27, 2008 7:47:04 PM
"...we should have an underground city, that functions like any other city today but is ready to preserve technology and American culture in case of a global disaster" 3 words, LOL.
Posted by: marzbite | Jul 27, 2008 8:11:13 PM
A nuke probably wouldn't incinerate the asteroid into nothing. It could potentially create scattershot - so instead of us getting hit by a single asteroid, we could be pelted with fragments.
(I imagine the latter is probably better than the former most of the time, but ideally, we would want to get hit with nothing. That's the preferred outcome.)
Posted by: I agree with him. | Jul 27, 2008 8:29:06 PM
Physics, people. It's not just a buzzword.
Posted by: Ben | Jul 27, 2008 8:36:02 PM
Note to Cyberian: nice try, but slowing it down so that we can use it requires more energy that simply lifting the raw materials from earth or mars or venus.
Posted by: Harmonious Botch | Jul 27, 2008 8:55:59 PM
Remember people, if you simply blow something up (especially with an explosion at its center) you don't change the path of its center of mass. So excellent chance some or much of it ends up hitting close to where it was going. You need an offset force applied in the right direction, and not very much force if you start far enough away, to change the path and just miss Earth. NDT's gravitational tether is interesting but probably too slow. I'd land a spacecraft on the proper side of the rock with a good size rocket engine facing "up". Then do a controlled burn to change the path enough. A lot more civilized and certain than nuking it.
Posted by: Georgie | Jul 27, 2008 9:17:42 PM
You use nukes, but not big nukes to break up the mass. That doesn't change the trajectory of the debris.
It *does* break up that debris, which might make a collision even *worse*, since you've got dozens of smaller masses hitting like a shotgun blast rather than a single mass hitting like a bullet.
Instead, you use many many *very* *low* *yield* nukes to alter the asteroid's trajectory without breaking it up. Use them as a nuclear pulse drive. Look up "Project Orion" in Wikipedia.
Best thing would be to keep nudging that trajectory until the asteroid is in a nice stable orbit around earth. Than start mining it for whatever raw materials it contains. Or use it for a trans-shipment station. Or use it for an experiment station.
Posted by: Stormcrow | Jul 27, 2008 9:40:30 PM
Another thing to consider, would be a super high velocity mass driver cannon, moon based if possible, that could fire large projectiles, at a fairly constant rate, to change the trajectory over a period time.
Posted by: Mel | Jul 27, 2008 10:10:31 PM
Im sorry to say that if a massive NEO meteor chooses our path, there is beyond little that we can do to stop it. These are all just pathetic theories all with VERY high probability of failure. Im afraid if its literally in our cosmos to be hit, then it will simply happen. No amount of preparedness can change that. Imagine if you will bacteria on a basketballs surface, now shoot a bullet at it and tell me the bacteria have a chance to stop it? NO. The sheer physics of it are unimaginable. We have about as much of a chance as we have of changing our own orbit at the last second to dodge it. Slim to none. It wont of course stop people from speculating, trying, and hoping.
Posted by: einstein | Jul 27, 2008 10:59:50 PM
We just need to point Hercules and Peter the Great at it and use their nukes to drop it!
Seriously though,does anyone really believe if the US government wanted nukes in space they would need an excuse? They'd just put up an "observation sat" with the nukes onboard. In fact it really wouldn't surprise me if the US and Russia does already have a warhead or two up there as a "got ya last".
Posted by: kb | Jul 27, 2008 11:03:05 PM
You don't need to use nuclear material to blow up asteroids, or even blow up nuclear weapons to move asteroids.
If you were to make a nuclear "rocket " (basically a Uranium-based liquid contained in a magnetic toroid bottle, check NASA's website, as they came up with this idea back in the 50's) you could actually use the material from the asteroid itself as the propulsion mass. The Uranium would generate massive heat, yet be contained within the toroid. The heat could then be used to melt a portion of the asteroid mass (such as water ice if it could be found on the asteroid, or most any material that has a low enough melting point) and then passed through the center of the toroid. This superheated matter would then be jetted out of the "rocket" at extremely high speeds, thus providing the thrust needed to nudge the asteroid into orbit as opposed to striking the earth. The asteroid would then be available for mining.
Posted by: | Jul 27, 2008 11:09:22 PM
Asteroids aren't exactly bright shining stars, last I read we'd have a 6 month warning if there was one heading directly for Earth. At that point, all a nuclear bomb would do is irradiate it, so we would be worried about a radioactive asteroid heading for Earth.
Posted by: | Jul 28, 2008 12:33:52 AM
If they wanted to put nuclear weapons in space, we can expect a world event where an "asteroid" hits the Earth. After that, we's hear some leader say "you are with us or with the asteroids."
Posted by: | Jul 28, 2008 1:18:14 AM
the old theory depends on nuke's shockwave after explosion.
there is no AIR in space.
so there is no shockwave. so its like a trying to kick a man down with x-ray machine. have you ever been at doctor? do you feel a punch when they take a picture?
i'm not saying what even towing etc will help. just what we are so tied on earth to our common thinking models - if explosion works on earth, why cant it work in space etc. yeah. well try to shoot a "normal" gun in space. there is no air or oxygen. it will not burn. so there is no explosion
Posted by: think a bit out of the box | Jul 28, 2008 2:47:48 AM
Wow, lot of scientists that have a clue about all of this here...
Posted by: xxx | Jul 28, 2008 2:51:54 AM
I think an anti-matter torpedo would be the best solution. Or maybe a repulsion ray.
Posted by: jojo | Jul 28, 2008 3:26:33 AM
I am in despair over the sheer brilliance and solid grasp of science shown by the comments here.
Let's see - asteroids are either metallic carbonaceous (glorified dirty snowballs) or silicaceous (stony); carbonaceous asteroids are 75% of the asteroid population, and they are not unitary bodies. Firing a nuclear missile at a carbonaceous asteroid is kind of like firing a 20mm cannon at an avalanche - well, if it makes you feel any better ... and not utterly stupid!!!
The only way I can see to affect that is to change the orbit, and the best ideas I've seen are emplanting a rocket on the surface to move out of the collision orbit with slow, measured firings, Rusty's idea of gravitational tug-boating, and an idea I've thought on, using a high-powered laser stationed at a distance to ablate various parts of the asteroid in order for the reaction to alter its orbit.
In addition, you want to mine asteroids, and blowing them to kingdom come means you lose them, big-time. As far as nuclear explosions affecting asteroids, the radiation does it - but it does it in an uncontrollable manner - and that is like demolishing a building by sticking a big pile of explosives in the basement. Not the way the professionals do it.
Posted by: Wesley Parish | Jul 28, 2008 3:29:54 AM
does anyone else think that by seeing these "threats" to earth that we will in turn "threaten" ourselves with chaos and wars?
what happens if one country wants to bump the asteroid and another wants to blow it up and another wants to leave it alone... that it causes a war of greater magnitude then ever seen before?
Posted by: huh i hear world war 3.. and it sounds like an asteroid. | Jul 28, 2008 3:33:09 AM
you would need a really big bomb to do serious damage *blow it apart* and right now the only thing that would come close are theories regarding a Helium 3 detonation...*destroyer of worlds compound found in moon rocks-if harvested, refined and turned into a weapon..would = enough power to rip apart continents*- (thought of as the next evolution to nuclear fuel and possibly the fuel to begin intergalactic space travel and that's only if the moon has A LOT of this material and if we ever figure out the reactor tech behind it..)
but to push it..umm not so much so..granted you have to fly to catch up to it- and then land something or smack it..to exact a force over a very large distance..is about all we could do right now...even if you could push it an inch..that inch would become 1,000's of miles over the course of interstellar distances...
yeaa
Posted by: kfoss | Jul 28, 2008 3:47:02 AM
A 50 Gton nuclear bomb is an effective solution vs a 500-1000 mt diameter asteroid: pulverized! No way. If an asteroid colliding the Earth is fragmented by a nuke the global damage will be reduced. We have this bomb NOW ... it is not a tech far 30 years. .... a excuse for put nukes in space??? Do You really believe that putting some nuke in the space will allow someone to gain the control of the World?? A nuke in the space may allow a strategic dominance? NO!
Posted by: l | Jul 28, 2008 3:52:25 AM
Former astronaut Ed Lu is working with Schweickart at the B612 Foundation and he's one of the primary figures in the August National Geo story "Impact Earth," which posits nuclear weapons as a last resort, not a first:
"Now an executive at Google, [Lu] is helping design a massive database for a successor to Pan-STARRS, the Large Synoptic Survey Telescope, which will scrutinize the sky in even more detail starting in 2014. Lu is also the coauthor of a scheme for using a spacecraft to coax an earthbound asteroid off its dangerous path. “We were originally thinking about how you would land on an asteroid and push it,” he says. "But that doesn't work well." If the surface is crumbly, the lander might skid off. Moreover, asteroids twirl through space. "If you're pushing and the thing is rotating, the pushing just cancels out," Lu says.
Then he and Stanley Love, a fellow astronaut, realized pulling would be much easier. A spacecraft could hover nearby and fire its thrusters, gently tugging the asteroid along. No harpooning or lassoing would be required. "Rather than having a physical line between you and the thing you're towing, you're just using the force of gravity between them," Lu says. The "gravity tractor" would tug the asteroid off course at a mere fraction of a mile an hour. But this subtle shift, magnified over the vastness of space, could mean missing Earth by tens of thousands of miles.
Lu's scheme would work only for asteroids up to a few hundred yards across that could be engaged far from Earth. If a small rock sneaks up on us, we could try ramming it with a spacecraft. But there's a drawback, says Morrison: "If you hit an asteroid with enough energy to break it apart, but not necessarily enough energy to disperse it widely, you now have a flying collection of stuff. You have to ask how practical that is." When all else fails, and for large asteroids and comets, only one strategy has a chance of working: We'll have to bomb them back to the Stone Age."
http://ngm.nationalgeographic.com/2008/08/earth-scars/stone-text/1
Posted by: Marilyn Terrell | Jul 28, 2008 3:53:50 AM
Asteroids are just God's way of saying it's time for "Earth, V1.2"
Posted by: Robert Raymond | Jul 28, 2008 4:47:02 AM
You could attempt a deflection by hitting a large asteroid with smaller and more controllable ones. It has been proved that nukes are far too puny to effect any change in trajectory. You guys just want to see the fireworks!
Posted by: pATREUS | Jul 28, 2008 4:50:58 AM
Everyone is FORGETTING SOMETHING!!...An Asteroid a few miles wide could very easliy be blown up with a thermonuclear device, and the remains would most likely burn up in our thick atmosphere...however, the parts of the asteroid that do remain would be highly radioactive. So we would have to ensure that they do not enter our atmosphere, otherwise there may be consequences...what if the debris from an asteroid were to fall above a city like Los Angeles or New York...
Posted by: The Puppet Master | Jul 28, 2008 5:02:11 AM
I'd want to ride the asteroid down.
Posted by: | Jul 28, 2008 5:38:25 AM
Ha Ha i had a good laugh reading alot of these posts. specially the drilling to a killer soundtrack. The truth is todays technology is able to track moving objects with our solar system and beyond months before they can collide with our little blue sphere. In fact there are many good possible solutions that all can work 1. Nuking the asteriod can break up the rock and thus dividing the masses kinetic energy among smaller masses. Consider this, just say 1 mass of 1 cubic mile is nuked into 1000 masses each mass has exactly 1/1000th the kinetic energy of the orginal mass unless the nuke alters the speed of the mass. A simple way to look at it is take it to the grain value and see if the impact is the same and then work in reverse. 2. Any slight change in the trajectory of the mass is greatly magnified by the time the mass reaches the target thus the force required would be minimal. I watched a documentry recently that speculated that in the future a powerful laser could apply a gentle force on the mass slightly changing the objects path over months or years. 3. Building a city underground or just a bomb shelter would need to serve humans/animals for centuries before we could sustain life above again, my opinion the lucky ones were nuked on the earths surface at the time of impact.
Posted by: Muzza | Jul 28, 2008 6:21:44 AM
If we can keep some nukes on moon base with nuke power rockets we may be able to distroy them at a much further away than sending a nuke from earth i believe.
Posted by: chanaka de silva | Jul 28, 2008 6:23:07 AM
Has no one seen Superman II? Lauching a nuke in space will release terrible Kyrptonite henchmen upon Planet Earth. Duh.
Posted by: Jim | Jul 28, 2008 6:28:53 AM
HANCOCK!
Posted by: Muzza | Jul 28, 2008 6:29:06 AM
I agree that nuking asteroids is not the best idea. We need to find a way to just redirect them to the mid-east.
Posted by: UHUH | Jul 28, 2008 6:47:38 AM
nasa
Posted by: sarika | Jul 28, 2008 7:01:44 AM
Kryptonite henchmen! gahh!
holy crap, after reading these comments, i am much more fearful of the gen pop than any asteroid.
i say bring it! It's clear that Earth needs a cleansing.
And there's already plenty of underground cities. The political elite from all first world nations have their *sses covered. Meanwhile, we'll be radioactive zombies on the surface!
Posted by: tim | Jul 28, 2008 7:02:44 AM
Whadda ya mean, Bruce Willis died for naught?????
Posted by: Land Shark | Jul 28, 2008 7:26:31 AM
Small delta vee change at long range = large displacement at target area. The key is early detection + having assets in place. You don't have to pulverize or stop the damn thing, just move it out of the 'strike zone'.
As to 'recycling'- easier to go to the Belt and push one in than to capture a near one (it's a long drop down the well, and those things are MOVING this close to Sol). Plus you can pick the type you want. But if we have that choice, why not mine it in place and 'drop' the refined goods to where we can more easily retrieve them. The good stuff will mass a lot less and you don't have to waste fuel on the dross.
Posted by: lazyeight | Jul 28, 2008 8:22:54 AM
Okay, so the planet hasn't been hit by anything dangerous in a lot of time...and so NASA thinks that just because it can interfere that it should. Who said that NASA should start making decisions for everyone? Now seriously the only question is when NASA will destroy the balance of the universe, and by how much they'll speed up the destruction of this planet.
Posted by: Dee-out-fowl | Jul 28, 2008 8:30:07 AM
Have we even considered the very real possibility that the "asteroid" is really a giant orb of pure evil, and that sending nukes at it will only make it bigger? I mean, the Fifth Element may be science fiction today, but tomorrow it may become reality.
Hmm, another Bruce Willis movie.
Posted by: Paavopetie | Jul 28, 2008 8:51:06 AM
We should use the moon as a shield. Duh.
Posted by: | Jul 28, 2008 8:56:12 AM
I dunno, seems pretty logical to me.
Posted by: JIm Woods | Jul 28, 2008 8:56:24 AM
Man, the critters on Mars are going to be pissed off when we tug an asteroid away from us, directly onto them.
I say we perfect this technology now, so when we do have to face aliens, we can just tug asteroids at them.
Posted by: Rick | Jul 28, 2008 8:59:12 AM
I would like to point out that if the human race was threatened with immenent doom we wouldent just send one nuclear weapon after it we would problem launch dozens if not hundreds (we made thousands in the cold war) and to answer the comment if it breaks up Great problem solved (if it breaks up it will have a higher surface area thus more drag when it hits the atmosphere and is more likely to burn up. and for the comment about radiation space is already highly radioactive. http://www.youtube.com/watch?v=KFXlrn6-ypg
Posted by: Marshkillz | Jul 28, 2008 9:01:09 AM
I say we land on it, strap rockets to it and change it's trajectory. Then we direct it into a wide orbit around earth and then build condos on it.
PROFIT!
Posted by: Steve | Jul 28, 2008 9:02:09 AM
@Dee-out-fowl: Choose another species, please. Humanity doesn't need you.
.
Seriously, deflection is a huge issue. We do not have the technology to deflect anything at present. We need large, space-based assets to detect and intervene in the course of a large impactor. Worse. To do anything with our current technology, we would need years if not decades of advance warning.
.
The truth is that today, if we found a NEO a mile in diameter or larger on a collision course with Earth we would be dead with anything less than ten years warning. We simply can NOT move an object as big as a mile.
.
The threat from NEO imapctors is rather small - statistically. But because it only takes one to erase all life on earth (except some lucky microbes) the threat needs to be taken seriously. We need to spend the money to learn how to place massive objects into space, move them and ultimately use them to perform complex tasks like building prefab bases (or engines or solar sails) if we do not, it is not unlikely that in 100 to 1000 years we will all die.
Posted by: Vexxarr | Jul 28, 2008 9:07:08 AM
Yes, they are. You want to know why nukes are the best for this? Because it's all we got. People talk about magical technologies like space tugs, using laser, and attaching mass drivers to the thing. Those sound nice both those technologies are outside our ability and will be for sometime. We have to go with what we know. And that is nukes.
People always assume that we are going to send some robot out there or a bunch of missiles to blast the thing. That is not how it will be. It will be a manned mission just like on that bad movie with Bruce in it.
When it comes down to saving the planet experimental technologies are not going to cut it. It will be a manned mission, possibly one way, and the job will be done with nuclear demolitions, not nuclear weapons.
Anything else is just foolish right now.
Posted by: Jeff | Jul 28, 2008 9:09:55 AM
actually, a moon based mass driver, or "gauss cannon" isn't really above our tech, we have some rather large ones in use on earth, in the experimental stages, so it would be a viable option, IF it were in place when we detected and tracked the thing.
Posted by: Mel | Jul 28, 2008 9:21:20 AM
you guys all fail
the world will be over before an asteroid hits us
it's inevitable...USA will lose in the end...there's no helping them
Posted by: kevin kwong | Jul 28, 2008 9:24:19 AM
You need fly 2 teams of oil drillers, capcom freedom and capcom independence with AJ leading Independence and Harry leading Freedom. They will both be assigned different landing areas on the asteroid, make sure you don't land on an ironplate. They both need to drill to 800 feet, whichever team reaches 800 first, wins. Drop the nuke and get out of there. Make sure the remote detonator is not destroyed during the rock storm, otherwise someone will have to stay behind and manually blow the nuke. Don't forget to stop by the Russian Space Station (not a gas station).
Posted by: warren | Jul 28, 2008 9:34:53 AM
You have got to love all this "arm chair rocket science."
Posted by: Chet | Jul 28, 2008 9:39:22 AM
If the human race were to be threatened, I would hope it wouldn't take long for the industrialized nations to unite resources and lift restrictions in order to save the planet. Why don't we launch enough nuclear material into orbit in order to build a fission pile core that could be used as the engine to get us to the neighboring planets? Mostly because nations are afraid of what would happen if that nuclear payload were to be lost while being launched. I would think this whole worry would be moot as soon as the life of every soul on this planet was forfeit if we didn't act quickly and decisively.
If what it takes is a catastrophe that threatens all life on this planet to end this useless bickering over the limited resources on this rocky ball that has dominated human politics since the beginning of history, then may we fall into the sites of fate. I can assure you, that if natural disaster doesn't kill us, then we will do the job ourselves eventually unless we can overcome all the pettiness that keeps us divided.
Posted by: Afell | Jul 28, 2008 9:46:35 AM
@ think a bit out of the box.
A nuclear weapon would vaporise a portion of the surface of the asteroid, giving it a small nudge, plus the change in mass would alter the trajectory, no atmospheric shockwave needed. Your gun analogy also reveals the weakness in your science, a gun will work very nicely in a vacuum, the propellant contains its own oxidant like a rocket, as theres little air in a cartridge even on Earth. An asteroid only needs a very small nudge, by towing, we mean placing a mass near the asteroid and its gravity will gradually shift it. a 1m/s velocity change will result in the asteroid missing by thousands of miles over the course of an orbit.
Posted by: mikey | Jul 28, 2008 9:49:08 AM
Nukes are the solution to everything!
You hear me, goddammit?!!!! -EVERYTHING!!!!!!
Posted by: Gunnary Sergeant Hartman | Jul 28, 2008 10:11:36 AM
If we catch an astroid that would hit the earth in several years, altering its trajectory by the slightest amount would avert a disaster.....unless,however, it gets too close and turns into "Night of the Comet" where everyone turns into orange dust except for the partially exposed zombies!!
Seriously though, if it were to hit earth in 5 years and we give it a 1 mph nudge it would miss us by 43800 miles and turn us into zombies that have a much longer life span. World saved.
Posted by: Joenz | Jul 28, 2008 10:15:31 AM
I think we should ask Batman what he thinks. He's pretty smart. He stopped the Joker. That has to count for something. Who's with me.
Posted by: Powerfan5000 | Jul 28, 2008 10:20:02 AM
Rusty is just buying time till the o-shit day happens...,Bottom line if we dont use the power of the atom mankind will never make it off this rock
Posted by: Batman | Jul 28, 2008 10:37:58 AM
@Vexxarr
In 100 to 1000 years I plan to be very dead.
what, me worry?
Posted by: buzz lightyear | Jul 28, 2008 10:38:21 AM
What about a few thousand cases of M-80's and blackcats??
Posted by: Mr. Spanktastic | Jul 28, 2008 10:43:13 AM
I got an idea. How about some of you who don't have a fart of a clue what you are talking about actually try and educate yourselves instead of spewing idiot talking points.
I know physics is hard and all of that but some of you really are failing at the game of life. It isn't what you know as much as it's you haven't a clue what you don't know.
Posted by: Mike Puckett | Jul 28, 2008 10:49:06 AM
We ought to think about the other implications that this technology could bring. Imagine extremist terrorists nudging asteriods to collide with us on purpose...
Posted by: steel rat | Jul 28, 2008 10:53:47 AM
Given a smaller ELE object of course:
1. A broken up asteroid will lose more mass when it hits the atmosphere. The more surface area the more will burn up before it hits. That's a good thing.
2. A little nuclear waste on an asteroid that hits the surface means nothing. Compared to the impact of an asteroid a mile across, nuclear weapons are toys. I wouldn't be surprised if nuclear fusion resulted from the impact naturally. Why nuclear weapons have such a stigma, I'll never understand.
3. A bullet hitting a basketball is an entirely bad analogy. The scale speed for that situation would be well beyond the speed of light. Besides.. Ever hear of an asteroid creating an exit wound in a planet?
Posted by: 731 | Jul 28, 2008 10:55:20 AM
Well, this was fun.
2 problems:
1) If it is a real big one, there is absolutely nothing that we can do that will make any difference at all. Maybe hook some thrusters to earth and see if we can move earth out of it's way.
2)If it is a fairly small one, it's small potatoes and will for the most part burn up when it enters the atmosphere.
So, the only ones to worry about are the medium sized ones. The most important thing we can do i calculate how big they are and where they will land. It is a 70% or so chance it will fall in the ocean. If we don't know where it will land, issue a tsunami warning anyways.
If all else, just call me. I will sling it back to where Lex Luthor launched the asteroid.
Posted by: Clark Kent | Jul 28, 2008 11:15:09 AM
Question: how big is the ateroid in question? Are we talking Tunguska event size ateroid? Or a Phobos (Mar's moon) size asteroid? There's a very large difference between them.
A couple thousand Megaton's of nuclear material blown up on the side of the asteroid would almost certainly divert the asteroid by a couple inches, enough to completly knock it off course. However, one commentator did bring up that an explosion in expanding gas and that there is no gas in space. If so, we would probably launch a very dense sattelite with huge surface area at it's flank. Perhaps with a core of Depleted uranium. Even if it onlyknocked the course of an asteroid off by a few milimeters, it would still miss earth.
Of course, the army has a supercomputer they used to figure out the physics between collisions of missiles on tanks. I'm sure they could figure out the physics behind a nuclear warhead hitting a asteroid.
Posted by: Pantera | Jul 28, 2008 11:28:46 AM
731: Nicely put.
.
Nukes are not inherently evil, they are just tools. It all depends on what you use them for.
.
For those of you who would have the Earth hit by the asteroid rather than even consider using nukes, step aside. The rest of us will work our butts off to do whatever is necessary to nudge the damn thing out of the way. Nukes, gravity tugs, rockets; whatever it takes.
.
Most of us will intentionally and deliberately choose survival. We will probably outlast those who choose surrender.
Posted by: ZenDraken | Jul 28, 2008 11:35:56 AM
It's patently obvious that BusHitler, Cheney, Rove and the rest of the neocon criminal cabal are using asteroids as an excuse to weaponize space with nukes in contravention to international law. They're the real-life incarnations of the super evil characters from some Marvel comic book or a 1930's movie serial. Thank goodness they'll all be gone soon and, hopefully, in prison for the rest of their lives.
Posted by: Freedom_Lover | Jul 28, 2008 11:40:39 AM
"Right now, humans are not tracking most of the objects that could cause serious damage to earth" - but thankfully dolphins do, and they report back to NASA. Otherwise we wouldn't even know that there are evil space objects out there threatening our freedom.
... and I also really love when we're called upon to make "tough decisions" about spending fortunes on imaginary threats. Yarrr, I'll nuke it, cos I'm tough! Tough! Tough!
Keeping Iraq occupied for six weeks costs as much as HIV medicine for a whole year for everyone in the whole world who don't have access right now. How's that for a tough decision?
Posted by: perspective has left the building | Jul 28, 2008 11:45:56 AM
Wacko alert!!!
@Freedom_Lover
Get some help. I'm sure there are some medicines that can do some good.
Posted by: John | Jul 28, 2008 12:06:20 PM
Most people don't have the slightest clue how nuclear weapons would be used to redirect asteroids, so I'll fill in some important details.
First off, nuclear weapons would not be used to "blow up" asteroids, that is a silly movie idea that would not work in practice. Any asteroid small enough to blow up with a few nuclear weapons would not be a very significant threat to Earth anyway.
The method that would be used would be to explode a nuclear warhead a relatively short distance away from the surface of an asteroid. In the vacuum of space there is no fireball from a nuclear detonation, what you get instead is most of the energy of the warhead in the form of soft x-ray and neutron radiation (in an atmosphere much of this radiation is absorbed by the air, which super heats and creates the typical nuclear explosion fireball). This radiation will hit the surface of the asteroid and cause the material to ablate, this ablation will create a substantial thrust, which will move the asteroid every so slightly. With enough lead time and enough nudges from nuclear weapons, you can move even very large asteroids off of a collision course with Earth.
As you can see this is just a way to use the asteroid's own mass as reaction mass in a kind of improvised rocket, because nuclear weapons pack a lot of energy in a small amount of mass this is a pretty efficient design given the technology we have today.
Note that during the cold war both the US and the USSR looked into basing nuclear weapons in space and discovered that it's not at all worthwhile, so concerns of "militarization of space" are hugely overblown. For example, if you have an orbital nuclear weapons platform you have to wait for the platform to be in the right position to launch weapons on the target. And you have a fairly narrow launch window for a specific target. With Earth based ICBMs the launch window is 24/7 for any target anywhere.
Posted by: Robin Goodfellow | Jul 28, 2008 12:09:16 PM
"Freedom_Lover"
The more I hear you cry "Freedom! Freedom!" The louder I hear your chains rattle.
Posted by: Eric Arthur Blair | Jul 28, 2008 12:10:22 PM
You don't need to explode a nuke at the surface of an asteroid to move it. If the nuke explodes at a distance above the surface, there are four effects:
First, you get a shockwave, regardless of what Mr. "there's no atmosphere in space" seems to think. Look up the term 'Radiation Pressure'. Granted, the radiation pressure from a nuke is vastly smaller than an atmospheric pressure wave, but it still exists, and a small force distributed over a large area still induces motion.
Second, the blast will heat up one side of the asteroid. It can easily heat things up enough to boil off water or other low-specific-heat compounds, and those boiled-off molecules will fly away from the asteroid's surface. In effect, you'd convert a quarter of the asteroid's surface into a low-thrust engine pushing the asteroid away from the initial blast.
Third, an appropriately designed nuke could induce an electrical charge on the asteroid's surface. That charge would cause small particles (dust, sand, small gravel) to fly away from the parent mass, creating another low-thrust/large-area engine.
Fourth, any heat absorbed by the asteroid's surface and that doesn't get expelled with boiled-off particles or distributed throughout the entire asteroid will radiate back out to space, giving us another helping of radiation pressure.
Post a series of small nukes along an asteroid's projected path, and you could nudge it out of an impact orbit without ever risking fragmentation or even doing anything that looks terribly exciting. And the astronomers would have a field day collecting data on the structure and composition of the asteroid.
Posted by: Mike Stone | Jul 28, 2008 12:12:10 PM
Some people have forgotten that the force required to move an object in a gravity-less vacuum is significantly less than the force required to move an object on Earth. In order to move Apophis out of the way, only 1 ton of material is needed to move it far enough away from us to create a miss instead of a hit. Pesky, that whole "gravity" "no gravity" thing, isn't it? Guess what guys, knowing Newton's 3 laws does not make you a physicist. There is far more complexity to these types of situations than the vast majority of you can even comprehend, let alone come up with on your own. Someone with time and a curious streak - look up radiation pressure to see why the best option may be to simply paint or cover the object with a reflective material. Perhaps that same someone will check out why possibly exploiting the Yarkovsky effect may be the answer.
I suppose that while the thought of nukes gets people going, the concepts of physics are continuously ignored. Sad, considering the two are not mutually exclusive outside of Hollywood.
Posted by: ORLY? | Jul 28, 2008 12:28:49 PM
Earth is roughly 13,000 km in diameter, and zooms in its orbit at 107,000 km/hr. An object travelling perpendicular to earth's orbit plane would have a window of roughly 7-8 minutes to hit it; an object travelling in the same plane of the earth's orbit would have perhaps two chances 10-15 minutes wide depending of its position relative to earth's. In any case an earthbound object does not have all day to decide whether to strike or not, like some movies would like us to believe. Of course there's a whole ton of factors to take into account as well, but that's the beef of the matter. 20 minutes at most.
Now, should any asteroid disregard the above and plow on to earth nevertheless, the wisest thing to do is apply force in the same direction the object is moving; less inertia to overcome and the delta-v will send the object zooming in front of the earth the same way some people I know speed at railway crosses.
Any way you put it, there's no need for a nuke at all. You can station a large drone rocket and suitable hidrazine tank in orbit and precompute suitable tugging vectors. Should cost about the same as putting a space station up there.
Posted by: Land Shark | Jul 28, 2008 1:25:53 PM
Physics, shmysics -- these are weapons designed to intimidate or rain from space onto the heads of democratically elected heads of state who have the temerity to oppose BusHitler, Cheney, Rove and the rest of the neocon criminal cabal. You know who I mean -- real, popular leaders, like Hugo Chavez and the champion of all black Africans, Robert Mugabe.
BushCo. (unsuccessfully) tried to unseat Chavez years ago with an abortive coupe, and is currently undermining Mugabe (in order to steal Zimbabwe's mineral wealth) with propaganda diligently repeated by American right-wing lapdog media.
Just wait until November or December or January of '08 when another "terrorist" attack professionally implodes a few huge stadiums or even more skyscrapers. There will be no transition of power. The powers that be, however, will have nuclear weapons in orbit and be able to shape the wills of the rest of the world according to their diabolical designs.
Posted by: Freedom_Lover | Jul 28, 2008 1:54:13 PM
"We should use the moon as a shield. Duh."
.
This is a great idea! Then we don't have to spend a lot of money trying to get to the moon (because there might not be a moon anymore) and two, if the moon were pulverized, then we might have a set of rings like Saturn. Wouldn't that be cool?
Posted by: Jojo | Jul 28, 2008 1:57:36 PM
Bob: Momentum transferrs quite nicely from nuclear drtonations in a vacuum: Google "Project Orion"+"nuclear pulse"
This is not, of course, today's Orion spacecraft. Indeed, the asteroid movie 'Deep Impact' used what appeared to be a nuclear pulse driven ship.
The problem is, will astroids respond like an Orion pusher plate? Mettallic ones might, stony ones might not.
Posted by: Frank Glover | Jul 28, 2008 1:58:29 PM
Can't we do both?
Posted by: Joel | Jul 28, 2008 2:35:06 PM
@ZenDraken
No, nukes are inherently evil, because they were designed for the express purpose of causing enormous amounts of damage both to property and human life in one fell swoop. Given an alternate use, they will still be used primarily for intimidation of enemies and large-scale collateral damage.
Harnessing atomic power is good. The energy contained in a single atom is almost incomprehensible, and there are a million uses for that kind of energy and power when used nobly.
Weaponizing that power is bad. Period.
Posted by: smidget | Jul 28, 2008 3:36:27 PM
The physics of asteriods deflection has been covered sufficiently above, including how to propertly use a nuke (not direct impact explosion guys).
To summarize the methods involved:
1) our current technology has limited capability to determine the surface characteristics of small objects in space, so nearly all proposals involving a "landing" or "anchoring" or "pulling/pushing" of sorts are not reliable from the very begining. (also, given our current mission success rate on Mars landing, I wouldn't count on any plan that requires touching the asteriod)
2) well that leaves us with very few options left... "gravity tug" and "ablation type methods" (including nukes, laser pointing at it, etc).
2)a) Grav tug is a good idea because as long as the asteriod as mass, it will work. The down side is that we need to launch an ungodly amount of mass to an ungodly distance away with an ungodly amount of fuel to run the grav tug for long enough to work. Also, it has to be done much in advance, leaving little time margin. However, the CRITICAl problem is that grav tug has to be very close to the asteriod itself (because of physics). Imagine a funny shape asteriod rotating non-stop, spilling gas and rocks here and there. The task of station keeping would be beyond difficult.
2)b) Nuke is independent of surface characteristics, asteriod geometry or dynamics. You set one off clear to it, x-ray does its job in an "unpredictable" manner, shoots the asteriod off to "there". The good thing is, nuking is a one time thing, you try once, observe, if not, try again next day! If success, drink up! Nukes are so compact and light weight that you can carry multiple warheads on a single mission. It also allows ample time margin, as in, you don't have to detect the asteriod 40 years ahead so you can launch the grav tug 30 years ahead to pull the asteriod for 20 years to work.
2)c) Laser ablation is like nuking just way slower and more controlled. One has to think of the laser package and the energy source involved, which would be very difficult! Rest of it is like half-way between nuke and grav tug.
When the fate of the Earth and survival of mankind rest in your hand, you'd better have a good idea about physics, engineering and mission design. I'm certainly not experts of just about all three of them, but we should consider all three aspects. Physics is simple, Newton laws, energy conservation, momentum, etc, always works on paper. When you need to make it into something that actually performs on a real asteriod, some things become more difficult. When you consider the viability of the mission, and the possible need for a second shot, you think beyond physics and engineering. NASA would have definitely considered all three (if not more) before they say nuke is the best option. When Apollo astronaut Rusty Schweickart (he is no chumps I presume) says otherwise, you might also want to think about these criteria. Get thinking guys, Earth V1.2 depends on you!
Posted by: Phoenix | Jul 28, 2008 3:57:06 PM
What if they crashed a big rocket, like an un-mothballed Saturn V into the thing? What if the nose was retro-fittied with ultra hard, rigid materials, effectively making the thing a giant battering ram? You'd think that something like that moving at the speed that it does would do a decent job of deflection. But you never know, the trouble is how do you go about testing something like that?
Posted by: Michael | Jul 28, 2008 3:59:18 PM
Why do we have to apply force to get it off its trajectory? Why not use that force to accelerate it a little bit in the same direction it is going which requires less energy? If it is indeed going to hit us making it faster will cause it to miss us. We may look big from our perspective, but astronomically speaking, we are a pretty damn hard moving target with Jupiter standing guard for us with all its mighty gravity.
Posted by: A.F. | Jul 28, 2008 4:22:39 PM
Does anyone know the probability of the earth being hit by an asteroid within the next 200 years? I would say it is much less than the probability of the earht being destroyed by global warming. I hope I won't live that long to suffer in the predicting extreme living conditions. The joke is that we have developed a well-planned defense system to automatically beam any massive object off the orbit of the earth but by then no one soul is on earth to witness this.
Posted by: Dumbo | Jul 28, 2008 5:30:12 PM
Can't we just send Chuck Norris up there to blow on the asteroid?
But seriously, though, the Apocalypse of John is going to come true in about 10 years, so as long as nothing happens until then, we're good. Once that begins, there ain't no stopping it, no matter what the 'scientists' say.
Posted by: Chill Out | Jul 28, 2008 5:56:54 PM
@Dumbo "Does anyone know the probability of the earth being hit by an asteroid within the next 200 years?"--
The National Geo story quotes Ed Lu, physicist and former astronaut who's working with Rusty Schweikart at the B612 Foundation:
“Every couple of weeks,” says Lu, “we’re going to be finding another asteroid with like a one-in-a-thousand chance of hitting the Earth.”
http://ngm.nationalgeographic.com/2008/08/earth-scars/stone-text/2
The odds that asteroid Apophis ("the Destroyer") will hit Earth on an April Sunday in 2036 "are currently estimated at 1 in 45,000."
http://ngm.nationalgeographic.com/2008/08/earth-scars/stone-text/8
So yes, the probability is way higher than the earth being destroyed by global warming. The trouble is, only a handful of scientists are pondering what to do about it:
"Few experts are giving this much thought, says astronomer David Morrison of NASA’s Ames Research Center: 'The number would roughly staff a couple shifts at a McDonald’s.'"
http://ngm.nationalgeographic.com/2008/08/earth-scars/stone-text/6
Posted by: Marilyn Terrell | Jul 28, 2008 7:45:20 PM
Britney Spears blows her new boyfriend at the pool house http://www.bangbull.com/details/29037-6F8/Britney_Spears_Blowjob.html
Posted by: Garf | Jul 28, 2008 10:43:18 PM
@Dumbo:
The Earth will not be destroyed by global warming any more than it was destroyed the last time it happened in the Jurassic. Us mammals did just fine back then. :) Nor will any reasonably sized asteroid destroy the Earth. It might destroy our crops, sure.
In any case, we are full of ourselves.
Posted by: 731 | Jul 29, 2008 5:15:05 AM
On trying to put it in fixed earth orbit to mine it:
Two words: EPIC FAIL.
If this were even possible (it's not, for all the reasons below), it would be a hugely bad idea. Why? Orbital decay. We can't even stop 5-ton satellites from crashing into the earth when their orbits decay, what is going to stop a 100,000,000 ton orbital object from falling once its orbit decays? Nothing.
On trying to hit it with a large, dense mass:
Great idea, but... launching a spacecraft with something big/heavy/dense/depleted uranium in its nose just isn't feasible. There is nothing that is going to be able to launch anything anywhere nearly that massive. A Saturn V wouldn't even come close. The amount of energy that would be needed to release an object that massive from the earth's gravity would require force at a higher order of magnitude than a nuclear blast.
As to attaching rockets to the mass: There is no amount of rockets that is feasible to attach to the mass that would have enough force to move it. The only technology we have that produces enough force to move a mass with that much momentum is nuclear explosions, controlled or otherwise.
Now for the nukes...
You are right that nukes need a blast medium of some sort in order to produce a blast wave. A bunker busting type device would use the mass of the asteroid itself as that medium. While it wouldn't likely completely destroy a ELE-sized mass (though the carbonacious type masses would likely be broken up significantly, as huge amounts of steam would be created internally), it could cause enough deflection if detonated in the right location (either right or left flank, speeding it up slightly and deflecting it slightly right or left) to knock it "out of the window" and prevent the primary mass from earth collision. The stuff that broke off would not likely be "radioactive waste" as some put it, due to the fact that the radioactive dust would be destroyed on reentry, as would most radioactive surfaces of larger pieces (gross radiation from the weapon itself is completely irrelevant as exponentially larger amounts of radioactive particles/waves bombard the ionosphere every day from the sun).
Also, anyone that suggested that a lot of smaller masses would be worse than one large mass could not be more wrong. Think of it like this... When thrown with the same force, which would hurt more, getting hit with a 2 lb rock, or getting hit with 2 lbs of small gravel? Additionally, the larger surface area of the multiple pieces facilitates greater disintigration when entering the earth's atmosphere.
Posted by: Brendan | Jul 29, 2008 7:23:03 AM
"...we should have an underground city, that functions like any other city today but is ready to preserve technology and American culture in case of a global disaster"
5 words: "A Boy And His Dog"
Posted by: Chuck Darwin | Jul 30, 2008 12:23:46 AM
They sure could do a bang up job of nudging the asteroid off of its course. Nukes can do more than blow stuff up.