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New Best Way To Nuke a Short-Notice Asteroid

samzenpus posted about a year ago | from the blowing-up dept.

Space 311

doug141 writes "A scientist proposes the best way to deal with an asteroid on short notice is to hit it with an impactor, followed by a nuke in the crater. From the article: 'Bong Wie, director of the Asteroid Deflection Research Center at Iowa State University, described the system his team is developing to attendees at the International Space Development Conference in La Jolla, Calif., on May 23. The annual National Space Society gathering attracted hundreds from the space industry around the world. An anti-asteroid spacecraft would deliver a nuclear warhead to destroy an incoming threat before it could reach Earth, Wie said. The two-section spacecraft would consist of a kinetic energy impactor that would separate before arrival and blast a crater in the asteroid. The other half of the spacecraft would carry the nuclear weapon, which would then explode inside the crater after the vehicle impacted.'"

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311 comments

Love the way... (5, Funny)

stoofa (524247) | about a year ago | (#43858461)

...his name is the sound his plan would make.

Bong Wie!

Re:Love the way... (0)

Anonymous Coward | about a year ago | (#43858543)

Yes, because "Explosions don't go 'boom' in a vacuum!"

Re:Love the way... (1)

Anonymous Coward | about a year ago | (#43858629)

Bong Wie!

I rather it be "Pong", just like the original video game

Re:Love the way... (1)

Intrepid imaginaut (1970940) | about a year ago | (#43858893)

Sounds half Filipino, half Chinese. I know a few Bongs, a Cherry Pie, a Zip and a Bing.

Re:Love the way... (1)

Anonymous Coward | about a year ago | (#43859267)

How about a Krystal Ball?... http://en.wikipedia.org/wiki/Krystal_Ball

Re:Love the way... (1)

rossdee (243626) | about a year ago | (#43859289)

"and a Bing."

Is that who the Micro$oft Search engine is named after? (Or was it the guy that sang White Christmas)

how short is the notice? (2)

Swampash (1131503) | about a year ago | (#43858465)

Wouldn't it be more efficient to just... push the asteroid out of the way?

Re:how short is the notice? (5, Informative)

heypete (60671) | about a year ago | (#43858493)

If you have the time for it, sure.

As the article says,

A nuclear weapon is the only thing that would work against an asteroid on short notice, Wie added. Other systems designed to divert an asteroid such as tugboats, gravity tractors, solar sails and mass drivers would require 10 or 20 years of advance notice.

It's not really possible to put big rocket motors on an asteroid and push it out of the way, as transporting enough fuel to the asteroid would be unbelievably expensive and likely infeasible with current technology.

Re:how short is the notice? (4, Insightful)

Anonymous Coward | about a year ago | (#43858623)

If we're facing a potential wipe-out of several major coastal cities, I'm hoping we would get some leeway on expenses.

Probably not though. :(
I'm sure we would still be fighting over who would pay for it, or some other political bullshit [theonion.com] when it hit and killed us all.

Re:how short is the notice? (1)

firex726 (1188453) | about a year ago | (#43859177)

Well think about how much fuel was used for the shuttle. Shuttle was around 165,000 Lbs empty; but adding in the fuel and external tanks/boosters we're looking at a whopping 4.4 Million Lbs that needs to get off the ground.

Now compare that to the Chicxulub meteorite that killed the Dinosaurs, it was 10 Km in diameter; pretty sure it'll take a bit more fuel to divert something like that.

Re:how short is the notice? (0)

Anonymous Coward | about a year ago | (#43858701)

Nonsense. You'd just use the asteroid *itself* as fuel.
As long as it's not made of iron, you can always either use fusion or fission. Both of which being something we already did in bomb form. (Although of course we may not have the experience to do it with *all* materials *yet*. But I don't think any asteroid is *pure* iron.)

Re:how short is the notice? (4, Insightful)

K. S. Kyosuke (729550) | about a year ago | (#43858829)

Nonsense. You'd just use the asteroid *itself* as fuel.

That's what the nuke does. The asteroid provides fuel (as in mass), and the nuke provides the energy.

Re:how short is the notice? (2)

Salgak1 (20136) | about a year ago | (#43858817)

Who needs fuel ? Send a nuclear-powered mass driver/excavator. Use the asteroidal itself as reaction mass. . . .

Re:how short is the notice? (2)

K. S. Kyosuke (729550) | about a year ago | (#43858821)

Wouldn't it be more efficient to just... push the asteroid out of the way?

Actually, probably an easier and more reliable way would be to simply let a hardened nuke hit the asteroid and have it explode some 10-15 meters below the surface. We already have these (or rather, you Americans do - look up B61 Mod 11), and these are built to penetrate reinforced concrete. The majority of asteroids has a vastly softer composition. The plasma ejected from the explosion will make its own nozzle on-the-fly, so as to speak.

Re:how short is the notice? (0)

Charliemopps (1157495) | about a year ago | (#43859029)

We wont know what it's made of... but there's a high likelihood it'll be solid iron. We don't have anything that can penetrate 15 meters of solid iron in-tact.

Re:how short is the notice? (4, Informative)

K. S. Kyosuke (729550) | about a year ago | (#43859191)

I believe we're quite capable of telling the composition from remote observation and adjusting the plan accordingly. Also, some M-type asteroids (such as 16 Psyche, to name the most notorious example) do have significant quantities of iron, but I don't think that the majority of even the metallic M-type asteroids are solid iron. "High likelihood" is really an exaggeration.

Armageddon (0)

prasadsurve (665770) | about a year ago | (#43858475)

Or we could have Bruce Willis and his team dig a hole to put the nuke in.

Re:Armageddon (1)

Anonymous Coward | about a year ago | (#43859207)

Only if we can leave him there. Sadly however, it only might prevent him from doing another 'die hard' sequel.

Re:Armageddon (0)

Anonymous Coward | about a year ago | (#43859233)

That was my first thought: wasn't there a movie about this? You know science is clueless when it starts immitating Hollywood. Maybe they should send Lindsey Lohan. She needs to get away from here anyway.

Sheesh... (0)

Anonymous Coward | about a year ago | (#43858483)

Will this be in time for the one coming near us on the 31st?

Re:Sheesh... (1)

Mike Frett (2811077) | about a year ago | (#43858631)

1998 QE2 will be about 3 Million miles away. I think we're pretty safe, no Nukes needed. =)

Re:Sheesh... (4, Interesting)

peragrin (659227) | about a year ago | (#43858733)

But if we fired off two or three hundred nukes we can claim those as part of the disarming campaign, test them in live fire conditions, increase the exposure of space travel to people, and watch a bunch of real big light shows.

that is like 5 wins.

Re:Sheesh... (1)

Askmum (1038780) | about a year ago | (#43858939)

1998 QE2 will be about 3 Million miles away. I think we're pretty safe, no Nukes needed. =)

How about 1969 QE2 then. Reportedly that's a lot closer already.

Re:Sheesh... (3, Interesting)

Grizzley9 (1407005) | about a year ago | (#43859201)

1998 QE2 will be about 3 Million miles away. I think we're pretty safe, no Nukes needed. =)

Wouldn't that make for a good test case though? I'd hope our first attempt at deflecting an asteroid isn't our one shot at survival. With it being so far away you could do a test on it and gather some valuable data.

But Why? (2)

MichaelSmith (789609) | about a year ago | (#43858561)

Any object small enough to be destroyed this way would be best avoided by evacuating the locale where it is going to hit.

Re:But Why? (4, Insightful)

Verunks (1000826) | about a year ago | (#43858595)

because it's less expensive than rebuild a city?

Re:But Why? (3, Insightful)

K. S. Kyosuke (729550) | about a year ago | (#43858843)

Letting it wipe out all life completely is the cheapest option at all - you don't spend a cent on rebuilding anything. :-)

Re:But Why? (0)

Anonymous Coward | about a year ago | (#43859243)

Letting it wipe out all life completely is the cheapest option at all - you don't spend a cent on rebuilding anything. :-)

That's the teabagger plan

Re:But Why? (4, Insightful)

MacGyver2210 (1053110) | about a year ago | (#43858619)

It's not DESTROYING the incoming asteroid, it's breaking it up into smaller pieces and changing their trajectory. The point isn't to get the asteroid to miss us entirely, it's to make it not hit us all at once in one spot.

Small impacts would probably be pretty devastating for those that survive the atmosphere(think early impacts from Armageddon, etc) but at least it wouldn't cause a near-extinction of all life as a giant single impact could.

Re:But Why? (0)

Anonymous Coward | about a year ago | (#43858715)

Actually if you break a large object into many small objects the pieces still have the same total kinetic energy. It turns out that distributing the energy over a larger area is actually worse as while each place may be slightly better off it will still be uninhabitable (assuming a large asteroid), but there will be fewer areas sufficiently far from an impact to be unaffected.

Re:But Why? (5, Funny)

Anonymous Coward | about a year ago | (#43858807)

Yes, but by breaking it into smaller chunks you are increasing the surface area of the impactor. Its mass obviously stays the same, so the surface area/mass ratio changes in your favour, which means more of the asteroid will get burned up in the atmosphere before hitting the Earth's surface. Of course it depends just how many bits you can smash it into as to whether or not this will be worthwhile.

Try it with ice cubes - fill two identical ice-cream tubs with water and freeze them. Smash one into bits (you don't need a nuclear warhead for this, but if you decide to use one please post a video on youtube) and put all the bits in a tray. Put the intact ice-lump onto a second tray and leave them side-by-side in the sun. See which one completely melts away first. Same amount of water, different mass/surface area ratios.

Re:But Why? (0)

K. S. Kyosuke (729550) | about a year ago | (#43858901)

Its mass obviously stays the same, so the surface area/mass ratio changes in your favour, which means more of the asteroid will get burned up in the atmosphere before hitting the Earth's surface.

Merely breaking it into pieces does not matter all that much, because it still gives off its kinetic energy and the results could be nasty anyway. For example, the Tunguska asteroid probably disintegrated in an airburst and gave off most of its energy some eight kilometers above the ground. You really don't need for that thing to hit the ground at high velocity.

Re:But Why? (1)

Aryden (1872756) | about a year ago | (#43858997)

2 things:
1) Smaller chunks would have a slightly different trajectory so that some would miss us entirely while others, being much smaller, would burn up in the atmosphere before their kinetic energy would reach a point to harm us.
2) Exploding 1 incredibly large roid in the the lower atmosphere would have the effect you are describing, but by breaking it up, the mass of the particles entering the lower atmosphere would be drastically smaller. Thus, creating less "dust cloud".

Re:But Why? (1)

K. S. Kyosuke (729550) | about a year ago | (#43859059)

1) Smaller chunks would have a slightly different trajectory so that some would miss us entirely while others, being much smaller, would burn up in the atmosphere before their kinetic energy would reach a point to harm us.

You are reiterating what I had already said somewhere else in this discussion.

but by breaking it up, the mass of the particles entering the lower atmosphere would be drastically smaller.

That is true, but it really doesn't matter all that much if 1.0e9 tons hit you in the form of a few large fragments or a million small ones. The energy is still the same (you can do basic arithmetics, can you?), and, e.g., the production of toxic nitrogen oxides from the atmosphere heating wouldn't be significantly diminished, especially if all the asteroid fragment energy is expended in the atmosphere rather than in a single impact site. The former effect you're mentioning (as well as I did) is much more important.

Re:But Why? (1)

Aryden (1872756) | about a year ago | (#43859235)

But it's not 1.0e9 tons hitting you in the fragmented instance. You're reasoning is that you explode the roid but all of the chunks still hit you when in reality, you would explode the roid and X chunks miss you entirely while Y chunks actually impact the atmosphere.

If you break a roid of 1.0e9 MT into 1000 smaller chunks, changing the trajectory of even 20% of the chunks such that they miss you entirely, you are reducing your impact mass by 200 million MT. That's a fairly significant number. This represents only what misses us entirely, not what would "skip" off the upper atmosphere.

Additionally, small pockets of gas/dust would settle and dissipate much faster than 1 very large pocket.

Also, you are removing the effect of the large mass impacting a single area creating either a tidal wave on an oceanic impact, or a massive dust cloud on a land impact.

Re:But Why? (1)

stenvar (2789879) | about a year ago | (#43859027)

Your nuke may not be strong enough to deflect the asteroid, but it may be strong enough to increase the area over which the pieces get dispersed many times, resulting in a much lower energy per area.

Re:But Why? (1)

K. S. Kyosuke (729550) | about a year ago | (#43859143)

Your nuke may not be strong enough to deflect the asteroid, but it may be strong enough to increase the area over which the pieces get dispersed many times

There's a continuum between these two. And yes, I'm aware of how basic physics works.

Re:But Why? (3, Interesting)

hattig (47930) | about a year ago | (#43859229)

I still prefer the odds on the broken up asteroid than the guaranteed end of human life full asteroid.

In addition it could be that many of the pieces will miss us anyway. The relative speed of the asteroid to earth could be as high as 70km/s, so if we hit it with 24 hours to go, that's 86400 seconds for each piece to shear away from us from a distance of 6 million km. We only need to change the asteroid piece trajectory slightly to make it miss the Earth entirely. Indeed it may be prudent to have a second warhead to explode after the first one to give the pieces more momentum away from the line of impact (we'd need around 100m/s, that's a lot of momentum to be giving to potentially massive lumps of rocky iron).

Re:But Why? (0)

Anonymous Coward | about a year ago | (#43858811)

The trajectory of the fragments would diverge so they would end up missing us. That's the whole point. Any which do come our way may burn up anyway.

Re:But Why? (0)

Anonymous Coward | about a year ago | (#43859255)

...and what if they don't? Radioactive fragments falling from the sky? Where do I sign up to live next to that? As per usual it doesn't sound like we're really thinking this through.

Re:But Why? (2)

K. S. Kyosuke (729550) | about a year ago | (#43858855)

Perturbation analysis, my friend. Despite the fact that the total energy will change very little, if it breaks up, most of the pieces will be unlikely to hit a single compact object - dispersion of their trajectories in the phase space. Picture a shotgun hitting you with only two smallish pellets rather then with all of them.

Re:But Why? (0)

Anonymous Coward | about a year ago | (#43859045)

I guess it will heavily depend on the asteroid. Remember that a nuclear explosion is not that big. Without an atmospheric shock wave by suddenly heated air and with an asteroid not that scared about radioactivity, for many asteroids a nuclear bomb might have hardly any effect. If it has an effect it might disperse it a bit but garvity might still keep it together (and it it is not done far enough away, even if it get a dissolving cloud of debris, that cloud might not be that big once it reaches earth).

So instead of a single impact, which with a small object would otherwise only destroy a small area and only have a effect if you are very very very unlucky that it is a city you'd get a large cloud that could inconvenience a larger area.

And if the asteroid is big enough to have a global effect, then having the whole earth atmosphere hit with enough material to burn much more than some little eject material from an impact can cause.

Would you rather get hit with a single bullet that has a chance to hit nothing important, or getting a load of shrapnel hitting your full body?

Or even more: would you rather be hit a by a 500g package of flour or by a cloud of flour nicely dispersed? What if someone put some flames before you?

Captcha: crossing

Re:But Why? (1)

MachineShedFred (621896) | about a year ago | (#43859263)

Also, breaking it up dramatically increases the surface area being affected by atmospheric entry forces. More is going to burn up, and more pieces are going to break off and go away during entry.

Re:But Why? (1)

xelah (176252) | about a year ago | (#43858791)

The politics must be fantastic.......break up an asteroid heading for New York and send some of the pieces to China/Russia/somewhere that could moan with violence. Or, of course, vice versa if the US legitimizes it.

Re:But Why? (1)

hcs_$reboot (1536101) | about a year ago | (#43858669)

And if it is big enough, we'll have to deal with the remaining debris of size asteroid/x, and if it is even bigger, we'll have to deal with each y debris-of-debris from the x debris pieces etc ... well, a good way to get rid of all nuclear warheads we currently have on Earth..

Re:But Why? (1)

necro81 (917438) | about a year ago | (#43859197)

Any object small enough to be destroyed this way would be best avoided by evacuating the locale where it is going to hit

In terms of having confidence that you'll save lives, you may be correct. In terms of property damage - it is difficult to be sure. An asteroid delivering even a glancing blow to a population center could easily cause several billion dollars of damage. I expect the whole cost of this program would be less than that.

A tough thing with small objects like this is that their trajectory through the atmosphere during entry is not as deterministic as much larger objects. And there's no guarantee that it'll make it all the way to the ground - you may well end up with an airburst, like in Chelyabinsk. So the size of the evacuation area would be huge: hundreds of square kilometers, and could affect millions of people. The costs of doing that kind of evacuation would also be enormous.

But who says you can't do both: prudence counsels that you try to damage/disrupt/avoid the threat in the first place, while also making preparations for what to do if that fails.

Spin spin.. (4, Informative)

hantms (2527172) | about a year ago | (#43858571)

Don't asteroids usually spin? If you blast a crater on one side, then you have some serious aiming to do to hit the crater?

Re:Spin spin.. (3, Funny)

hantms (2527172) | about a year ago | (#43858579)

Don't asteroids usually spin? If you blast a crater on one side, then you have some serious aiming to do to hit the crater?

Then again, clearly it's possible to hit with photon torpedoes, and using the Force.

Re:Spin spin.. (1)

MacGyver2210 (1053110) | about a year ago | (#43858625)

Planets and moons also spin, what's your point?

Re:Spin spin.. (0)

Anonymous Coward | about a year ago | (#43858809)

Planets and moons also spin, what's your point?

Because asteroids spin, it should be obvious that the center of the crater created by the first half may not be where it's needed when the second half hits.

There must be some distance between the kinetic device and the nuclear device to avoid destroying the nuclear device with debris from the first impact before it gets close enough to detonate, and that time difference could rotate the crater's center out of position. The true MacGyver would not only know this, but would be able to contrive a solution after the device had been launched.

Re:Spin spin.. (2)

hattig (47930) | about a year ago | (#43859291)

I'm sure they could space the two parts exactly one revolution apart (even taking the asteroid's relative velocity into account).

I think this is the type of problem done in high school mathematics?

Re:Spin spin.. (2, Interesting)

Anonymous Coward | about a year ago | (#43858681)

I'm not sure aiming would be a huge problem, computers are pretty good at that sort of thing. You'd probably have to have the two payloads on slightly different trajectories (one coming in from a bit of an angle) following separation to account for the 'roid's rotation.Imagine the asteroid at the centre of a clock face. First impactor would hit from a 5-to-12 direction, the nuclear warhead a few seconds later from 12 Oclock. This would require some manoeuvring after an early separation, but shouldn't be particularly difficult.

Alternatively, you could just pile the two impacts on in together from the same direction, just a few seconds (or less) apart so that there is only negligible rotation time between the two hits. Of course that risks your second payload getting hit by debris from the first impact, I don't know how much of a problem that would be. Maybe you could shield the second warhead against this, or shape the first impactor so that debris doesn't fly back up the wrong direction. Dunno. A lot would depend on how much is known of the asteroid's composition and the density of the impact site.

Finally, you could "hover" at a fixed point relative to the target, smash it with the first payload, wait for a a bit, then after one full rotation your second payload would be nicely lined up above the crater. Unless, of course, the first impact significantly changed the rotational speed / direction of the target...

Personally I like the idea of a rocket with a nuclear warhead in its belly and a great big one-shot frickin laser (chemical laser?) in the nose. Flies toward the target at high speed, then just before impact zaps a big hole in the surface, flies into the hole and detonates, kablooie!

Re:Spin spin.. (4, Informative)

AC-x (735297) | about a year ago | (#43858727)

Rocket scientists have managed to aim spacecraft to very specific points on spinning bodies before, I'm sure they'll manage.

Re:Spin spin.. (1)

meglon (1001833) | about a year ago | (#43858925)

Yeh....

It's easy to hit something once. When what you're trying to hit it with is moving at a basic set speed which may not allow enough change to compensate for the spin, then it becomes more difficult. Then, you have to think of it as closing velocity.... you get one shot, and that's pretty much it. If you miss, the first impact does nothing for you. The warhead part isn't going to be able to turn around, race ahead of the object, turn back around, and hit it in that hole (or try to) again.

I really don't think this would be as easy as you think it would be.

Re:Spin spin.. (1)

Anonymous Coward | about a year ago | (#43859047)

Israeli pilots did the exact same thing by hand in 1982 when they destroyed Iraq's nuclear reactor (albeit it was not spinning): some bombs cracked open the reactor dome, then the following pilot had to put his bombs through the hole - while avoiding sporadic antiaircraft fire (IIRC most of the Iraqi soldiers manning the AAA had gone to lunch).

Re:Spin spin.. (1)

poofmeisterp (650750) | about a year ago | (#43859105)

Don't asteroids usually spin? If you blast a crater on one side, then you have some serious aiming to do to hit the crater?

We have to try SOMETHING, even if it's a disgustingly planned attack almost guaranteed to fail.

Don't asteroids rotate? (2, Insightful)

will_die (586523) | about a year ago | (#43858577)

Looking at the article it does not look like they take into account the rotation of the asteroid. So do asteroids not rotate?
Even with a small rotation your nuclear bomb would miss the crater without some extra guidance which is not shown.

Re:Don't asteroids rotate? (4, Insightful)

AC-x (735297) | about a year ago | (#43858719)

What, you think someone smart enough to design a mission to intercept an asteroid with an impactor and hit that crater with a nuke wouldn't know to take the spin into account?

All this study was doing is working out whether the idea would work, not designing a complete mission profile for a specific asteroid.

Re:Don't asteroids rotate? (1)

peragrin (659227) | about a year ago | (#43858747)

what's happens when your crater causing nudge furthers changes the rotation?you literally have to plan for the final rotation change after the kinetic crater impact.

much simpler send up more than one nuke. Pepper the asteroid with them one after another after another.

We have thousands why skimp. More is always better.

Re:Don't asteroids rotate? (2, Insightful)

Anonymous Coward | about a year ago | (#43858907)

If we have a 1% risk of a rocket detonating during launch there might be reason to design a mission that only sends two rather than 1000.

Re:Don't asteroids rotate? (0)

Anonymous Coward | about a year ago | (#43858995)

There's the small issue that this would have to be done at rather long range so that the spacecraft wasn't destroyed / disabled by the first nuke. Also if the threat wasn't entirely certain it could increase the political difficulties involved with the launch.

Re:Don't asteroids rotate? (1)

poofmeisterp (650750) | about a year ago | (#43859119)

What, you think someone smart enough to design a mission to intercept an asteroid with an impactor and hit that crater with a nuke wouldn't know to take the spin into account?

All this study was doing is working out whether the idea would work, not designing a complete mission profile for a specific asteroid.

You know what you're doing in your comment? It's called assuming. The parent's question is pefectly valid and deserved a damned good discussion!

Re:Don't asteroids rotate? (0)

Anonymous Coward | about a year ago | (#43858865)

good idea - spin the asteroid at a high rate after the bomb is in the crater, then the explosion does even more scattering.

Simulate or it didn't happen! You know what I mean (2, Interesting)

CuteSteveJobs (1343851) | about a year ago | (#43858615)

A nudge I can understand if there is any way to create enough energy to push something that large out of the way, but what is the point of the nuke? How do we know this doesn't end up creating lots of smaller asteroids?

"The goal would be to fragment the asteroid into many pieces, which would then disperse along separate trajectories."
Uhhh. Ok.

"Wie believes that up to 99 percent or more of the asteroid pieces could end up missing the Earth, greatly limiting the impact on the planet."
Hell of a bet to take on a hunch. Where are the simulation runs or is this a touchy-feely? How do you know it won't vapourize a nice big hole inside like the underground nuclear tests?

"Of those that do reach our world, many would burn up in the atmosphere and pose no threat."
More ifs.

Sounds kind of flaky but he's got a $100K grant which I hope will answer these and good they are looking at *something*. I don't want to be an exhibit in a future sentient cockroach museum.

Re:Simulate or it didn't happen! You know what I m (3, Insightful)

Aryden (1872756) | about a year ago | (#43859025)

It's this thing called physics and specifically, astrophysics. You break these roids up into smaller pieces. The gravity of nearby planets and the sun would have a far more drastic effect on the smaller pieces as well as the energy from the explosion modifying the trajectory of the pieces.

Re:Simulate or it didn't happen! You know what I m (2)

david.given (6740) | about a year ago | (#43859171)

No, they wouldn't --- acceleration due to gravity is independent of the mass of the body. (The force due to gravity is GMm/r^2; acceleration is a=F/m; therefore the acceleration due to gravity is GMm/mr^2. The two m factors cancel out.)

What would happen is the nuke would push the fragments apart. These would continue to diverge, but would follow much the same course as the original asteroid. Whether they've been deflected enough to miss the Earth --- which is, of course, a really big target --- depends entirely on how hard the nuke pushed them and how long they travel before impact.

Re:Simulate or it didn't happen! You know what I m (2)

gatkinso (15975) | about a year ago | (#43859061)

I imagine the nuke shatters the asteroid, sending chunks flying, and Newton 2 then comes into play diverting the main body just enough to miss us.

Re:Simulate or it didn't happen! You know what I m (1)

poofmeisterp (650750) | about a year ago | (#43859153)

Sounds kind of flaky but he's got a $100K grant...

Come on, you gotta let people play with money in ways that are so slim to succeed that they'll need to ask for more to play with. It's how the aste.. err.. WORLD goes 'round.

And also, maybe he'll get to play with a nuke or at least watch during a test. Everyone wants to do it!

:-)

Shotgun (0)

Anonymous Coward | about a year ago | (#43858617)

So instead on on object hitting the earth, we'll have many fragments that are radioactive, great!

In reality the first we'll hear about one of these asteroids is when it becomes visible, which will be when it warns up, which will be when it hits our atmosphere, which will be about 1 second before impact!

Re:Shotgun (2)

SteveAstro (209000) | about a year ago | (#43858849)

So instead on on object hitting the earth, we'll have many fragments that are radioactive,!

Nukes can be designed to have a lot of residue, or not a lot of residue. I'll take mildly radioactive rocks than a wiped out city.

Re:Shotgun (0)

Anonymous Coward | about a year ago | (#43859077)

Only the bomb debris itself is radioactive, not the rocks that it is sticking to. It is one bomb. Taking global atmospheric testing into account we have already suffered some of the effects of a moderately size nuclear war.

And then it still hits (0)

Anonymous Coward | about a year ago | (#43858627)

So instead of an asteroid hit, we get a nuclear asteroid hit? I mean, in the case where the asteroid doesn't get deflected and it still hits us. Awesome!

Obvious answer (5, Funny)

maxwell demon (590494) | about a year ago | (#43858633)

Nuke it from orbit. It's the only way to be sure.

Re:Obvious answer (1)

RobinH (124750) | about a year ago | (#43858815)

"Nuke it in orbit. It's the only way to be sure."

FTFY

Re:Obvious answer (0)

Anonymous Coward | about a year ago | (#43858955)

"Nuke it into orbit. It's the only way to be sure."

And start mining

Messy solution (0)

marcroelofs (797176) | about a year ago | (#43858675)

If we'd be able to make a hole and then point a nuke into that hole we'd also be able to have it 'land' on the surface an explode/push the asteroid to a different track. Maybe 2 or 3 in a row.
Even if you could destroy an asteroid of significant magnitude with a nuke, it would be just as dangerous and less predictable afterwards.

I find it hard to believe that this is all a scientist can come up with.

Re:Messy solution (1)

Aryden (1872756) | about a year ago | (#43859075)

In your experience, is it easier to push 1 large and heavy object than it is to break that object into smaller pieces and push them individually? I know in my experience, it's easier to pack all of my books into small boxes and carry them than it is to try to move all of my bookshelves at once.

Re:Messy solution (1)

gatkinso (15975) | about a year ago | (#43859135)

The only prediction you need to know post strike is: will it miss? After that, who gives a damn.

Just send Bruce... (1)

ko7 (1990064) | about a year ago | (#43858717)

Us 'old guys' know how to kick some serious ass....

Re:Just send Bruce... (0)

Anonymous Coward | about a year ago | (#43859089)

Yeah, and you could call it "Springsteen on the rocks"

Sad (1)

ThatsNotPudding (1045640) | about a year ago | (#43858945)

Asteroid Deflection Research Center at Iowa State University

Meanwhile, my alma mater's big project is going to be a pork-barreled animal disease lab within eyesight of 50,000 respiratory tracts on gamedays. Ad Astra, my ass.

You know there is no explosive force in space... (0)

EmagGeek (574360) | about a year ago | (#43858963)

All a nuclear device would do in space is heat it up, pretty rapidly, maybe enough to thermal-stress-fracture it into several pieces, but nevertheless a nuclear weapon in space is not going to blow an asteroid (or anything else) to bits.

Re:You know there is no explosive force in space.. (1)

Christian Smith (3497) | about a year ago | (#43859139)

All a nuclear device would do in space is heat it up, pretty rapidly, maybe enough to thermal-stress-fracture it into several pieces, but nevertheless a nuclear weapon in space is not going to blow an asteroid (or anything else) to bits.

The heat would vapourize the rock, which would at least expand and exert some force on the rest of the asteroid. If the nuke was embedded in the asteroid before exploding, the vapourised rock would expand inside the asteroid, and probably significantly fracture the asteroid, perhaps into several pieces. And those individual pieces, as well as being less mass than the combined mass before (because of the mass lost to vapourised rock) would also be on a different trajectory to before, and so perhaps missing earth entirely. I think that's the point.

Also, don't think of asteroids as necessarily solid rock like you'd find on earth. They are just as likely to be coalesced space rubble, and not very tightly bound together due to insufficient gravity.

Re:You know there is no explosive force in space.. (1)

gatkinso (15975) | about a year ago | (#43859287)

Depending on the asteroid size and composition I'd be worried that the warhead would drill through the asteroid entirely and exit out the far side. I guess you could start a watchdog timer to trigger a few ms after impact no matter what.

Re:You know there is no explosive force in space.. (1)

poofmeisterp (650750) | about a year ago | (#43859179)

All a nuclear device would do in space is heat it up, pretty rapidly, maybe enough to thermal-stress-fracture it into several pieces, but nevertheless a nuclear weapon in space is not going to blow an asteroid (or anything else) to bits.

Well, we have to play with toys and money to test that and be sure.

Won't work if the asteroid is rotating (1)

Wormholio (729552) | about a year ago | (#43859133)

If the asteroid has any rotational motion then the crater created by the first impactor will have moved out of the way of the second.

Re:Won't work if the asteroid is rotating (1)

gatkinso (15975) | about a year ago | (#43859231)

Not going to matter much if the warhead is only a second or so behind.

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