Jeff, if you could please, you’re free to delete both this reply message and my (now very odd) one above it (dtd April 2, 2013, a 10:09 am). Thnx – – – BRC

This is so waaaay off-topic… it’s like… like… from another country!!
“BaDa-DUMP! Tissshhh!” *
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* — Drum-roll & cymbal-strike

http://abob.libs.uga.edu/bobk/ccc/cc050598.html

I think we definitely should consider sending Bruce Willis!

Great movie!

I am saying that even as a last resort it may only be just… futile and that praying may be at least as effective.

It’s not necessarily the number of nukes that counts but since you are talking multiple nukes the multiple shock interactions and effects on the fragments trajectories. It will be non deterministic at our available level of computational simulation, way too many variables and interactions. We may build an empirical model though by simulating 1 nuke – 1 rock, then 2 nukes – 1 rock, 2 nukes – 2 rocks but no one knows how many rocks/fragments will come off the first impact or impacts. And are you detonating in sequence, simultaneously,…?

BUT as I also said I am not 100% sure.

If Los Alamos is considering the option and dedicating some budget to it I guess it may have some value anyway.

As I first said way up above, when (not if) an Earth-smacking mass-people killing asteroid gets detected, we should “opt for ALL options” (i.e., implement: EVERYTHING!). All other other world priorities and “needs” (even world hunger) would have just been made OBE’d by the overriding need to SURVIVE at all costs.

http://www.space.com/14857-asteroid-nuclear-bomb-explosion-video.html

Pay attention to all the ifs and we believes… And they only seem to simulate the effect of the shock wave which is not enough but I am not a specialist. I would have to research a little more. For example I do not see the trajectory change of the various asteroid constituents/rocks after detonation.

And that

http://rt.com/news/asteroid-didymos-earth-blast-418/

What I was alluding to is that by blasting said rock at a distance from earth and from one side, while there would still be chunks falling earth-ward, there would be some percentage of that rock that would have hopefully been kicked off course.

Say… if a 100K ton mass was in an earth collision, and we lob X-number of Nukes onto one side, in an attempt to hard shove it off trajectory. If we assuming this to be a rocky asteroid, the impacts may break it up into chunks. Then another wave of nukes might be used to independently target the larger pieces. In the end, though, we will still have what amounts to a field of boulders are still headed our way. HOWEVER…

HOWEVER: The total mass of that resulting debris field still headed our way should be LESS than the original body! Not because of getting vaporized, but as a result some of that mass (just WAG-ing: 45 & 65% or 45K-65K tons) actually get pushed off course. Yes, we’ll still be hit, hit bad, but with at least some of the original mass gone, it would not the whole 100K ton ball of “whacks”

CMIshmael might be correct regarding “Half the mass in multiple smaller chunks is probably worse than the whole thing in one spot”. You could be right, CMI; but as I said way up front, this mode of defense is meant as a LAST resort for anything that gets past the further out mitigation measures. Even if you are correct, and an impact of ~51% of the original mass would still ruin humanity’s whole day… it might also not totally end it, versus getting smacked by a whole lot higher a percentage.

I’m simply saying that we ought not NOT do this, just because we might not guarantee <10% earth-hits. To make more sure, the Warmonger in me would say: "add even more Nukes"… or even a thimble of antimatter while we're at it… or, hell, even Rep Hall's frick'n (2-finger quote gestures) "LAY…ZERs". Bottom line, when faced with needing to conduct a last-resort effort (or you'll all die), you don't skimp on numbers or magnitude.

To put it another way — borrowing from a WWII pacific battle: when facing a banzai attack, you didn't fuss over what is the economical or safe (or these days "green") or minimal amount of bullets would be to do the trick. You TAKE AND USE EVERYTHING you've got and keep firing until either they have been STOPPED or you are DEAD.