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No Bomb Powerful Enough To Destroy an On-Rushing Asteroid, Sorry Bruce Willis
coondoggie writes "Maybe it's the doom predictions about the end of the Mayan calendar this year, or maybe these guys are obsessed with old Bruce Willis movies. Either way a class of physics students from the University of Leicester decided to evaluate whether or not the premise of Willis' 1998 'Armageddon' movie — where a group of oil drillers is sent by NASA to detonate nuclear devices on an asteroid that threatens to destroy Earth — could actually happen. The students found it would take a bomb about a billion times stronger than the biggest bomb ever detonated on Earth."
Armagedon is not that old at all.. uhmm.. ohmm...
Fuck, get of my lawn
We have a bomb that big! OoooOOOOOooh!
is it me or did the class get it wrong, it was never about destroying an asteroid, it was about splitting it up in pieces or nudging it out of the earth direction
"The biggest bomb ever detonated on earth" is a damn sight smaller than the biggest one ever built... Just sayin'.
Gosh, thanks. That must be why the other ships call me Meatfucker -- GCU Grey Area (Eccentric)
The students devised a formula to find the total amount of kinetic energy needed in relation to the volume of the asteroid pieces, their density, the clearance radius (which was taken as the radius of Earth plus 400 miles), the asteroid's pre-detonation velocity, and its distance from Earth at the point of detonation. Using the measurements and properties of the asteroid as stated in the film, the formula revealed that 800 trillion terajoules of energy would be required to split the asteroid in two with both pieces clearing the planet. However, the total energy output of Big Ivan "only comes to 418,000 terajoules. The asteroid is approximated as a spherical object 1000km in diameter
"First they came for the slanderers and i said nothing."
Forget Bruce Willis, you just have to land Chuck Norris up there and have him stomp his foot once.
Plot points based in hard science aren't exactly Michael Bay's MO...
This is the real paper, coming in at only 2 pages it's a light read: https://physics.le.ac.uk/journals/index.php/pst/article/viewFile/390/243
You weren't going to RTFA anyway, now were you?..
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P1_1 Could Bruce Willis Save the World?
Back A, Brown G, Hall B and Turner S
Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH.
November 1st, 2011
Abstract
The film Armageddon (1998) puts forward the possibility of using a nuclear weapon buried deep within an Earth-bound asteroid to split the asteroid in two, each half clearing opposite sides of the Earth with only relatively minor damage. This article investigates the feasibility of such a plan and shows that even using the largest nuclear weapon made to date, the bomb comes over 9 orders of magnitude short of the yield required.
[...]
You drill a hole in the asteroid and insert a nuclear device. Do not seal the hole. Explode the device. You get a volcano. Asteroid's material becomes the reaction mass (largely gases and small rocks.) Relatively small mass * relatively high speed = decent momentum. Repeat until satisfied. Call this project "Noiro."
Everyone knows that in such an event Sam will open a hyperspace window and the asteroid will fall right through.
"You know, you blow up one sun and suddenly everyone expects you to walk on water."
Lt. Col. Samanth Carter
Time is what keeps everything from happening all at once.
There was an asteroid in the film. You're thinking of Deep Impact: the same movie, cornier, with Elijah Wood, the homely-looking love interest and a comet.
Chewbacon
The Bible is like Wikipedia: written by a bunch of people and verifiable by questionable sources.
The last thing you want is lots of pieces - there's something called gravity which would cause them to re-agglutinate on the rest of the journey. Breaking up an asteroid takes far more energy than deflection, as should be obvious-despite the current illiteracy, it takes far less energy to brake a car than it does to break it up. Of course Hollywood wouldn't want deflection because there's nothing to see on screen - but deflecting it into a safe orbit would be much safer because you only have to predict the track of one object, not millions of small ones with different trajectories.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
... or so I misread the headline at first glance.
How else can you explain the time dilation of the painfully drawn out scene while the timer is ticking down and the audience is screaming "it's been minutes and supposed to be seconds - just die!".
Either than or about the fiftieth continuity or stupidly ignored fact failure of the movie.
There were Highlander sequals that made more sense - even the one where the sword changed from claymore to katana and back again in the middle of a fight.
Perfect excuse to develop and deploy Orion Drives, IMHO.
I've been curious...
The problem has been detecting it in time.
Down With Slashdot BETA!!! I've been around the corner and seen the oliphant; you can only abuse me from your perspecti
Another big point missed in the movie is that the Space Shuttle is only capable of going to Low Earth Orbit. Bruce Willis wouldn't have even been able to get the bomb there even if it was big enough.
Oh, yeah! Wise guy, huh? Woob woob woob woob! Nyuk! Nyuk!
Very doubtful. But we could potentially build such a bomb if the Earth depended on it for some reason; the Teller-Ulam configuration scales indefinitely. The problem is it'd be way too massive to get off the ground.
Of course, these students were simply calculating the (very unrealistic) scenario found in the movie, of the asteroid right about to impact, and of deflection involving splitting it in half and having one half go each way around the Earth. As they note, more realistic deflection scenarios involve hitting it much earlier and simply trying to alter it's trajectory intact (but that's not fitting for Hollywood)
Also it should be noted that the Tsar Bomba mentioned in the article was deliberately cut down to half of its design yield (replacing the uranium tamper with a lead one) to make it burn cleaner. It was not only the biggest atomic bomb ever detonated on Earth, but also the cleanest per unit of energy output.
Sometimes I doubt your commitment to Sparkle Motion.
Even worse: There are no asteroids with a diameter of 1000km. The largest of them, Ceres, is 950km and at a very safe distance in a very stable orbit. The second largest, Vesta, is less than 600km in diameter.
In fact, the main "danger" nowadays is seen in objects of about 0.1km in diameter, since that is the size at which asteroids are still damaging, but also escape early detection. That takes about 15 orders of magnitude off the energy requirements. But at this point, you wouldn't even need a bomb. Just shoving a few tons of stuff at a few km/s in front of the asteroid is enough to tear it apart. (The kinetic energy of 1t of material at 2.8km/s is equivalent to 1t of TNT.)
Yeah and Bruce Willis was in it too, it was called Hudson Hawk.
ACs don't waste your time replying, your posts are never seen by me.
If a planet killer asteroid was coming for the earth, I don't think it would be too difficult to get a pass on making an Orion space craft to act as a heavy lifter.
And I'm not talking about the NASA Orion I'm talking about the DARPA project
You've got the brackets in the wrong place.
It's not an old (Bruce Willis movie), it's an (old Bruce Willis) movie.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
OK. I think I've had this discussion before, but maybe people need a fucking refresher on basic newtonian motion.
BLOWING UP AN ONCOMING ASTEROID will ABSOLUTELY NOT 'MOVE' IT TO EITHER SIDE. My fucking GOD did the entire planet fucking fail basic physics? It WILL guarantee that we are, instead of being slammed with one giant rock, showered with millions of smaller rocks, but WE'LL STILL BE FUCKED SIDEWAYS in that scenario.
We could, yes, potentially build a really big bomb. It's not the fact that it's too "heavy" that is why it is impractical. It's because IT CAN NEVER, EVER, FUCKING EVER POSSIBLY WORK as a solution to an oncoming asteroid. That's because making a big rock into littler rocks is not how you stop it.
Diverting the asteroid is a LOT less expensive and though it is disappointingly big hardon-creating explosion-free, (Sorry Mr. Teller, your pyro days are in fact over as I recall) it actually has an advantage over just blowing up the asteroid in that it is a solution created by an adult and not the world's most-respected Beavis-inspiring physicist child who just liked to blow shit up, and that it would work
Sorry, had to get that one off my chest. Mr. Teller and his pyromaniac fantasies have caused a mighty disturbance in a conversation that needs to be deadly serious. We do not have time for the sniggering little Beavises of the world to fantasize about making great big fire. Jesus.
One day I feel I'm ahead of the wheel / the next it's rolling over me / I can get back on / I can get back on
I don't know about this. Depending on the composition of the asteroid, a bomb placed inside might possibly split it in half, and the force of that explosion would cause the two halves to move in opposite directions. If the bomb isn't powerful enough (quite likely with the size of a giant asteroid, and the size of our bombs), it won't cause the asteroid to be broken into "millions of smaller rocks", just two or so (again, this depends on the rock's composition). The problem is that it's unlikely the halves would be pushed apart enough to matter, so the whole thing is certainly quite unrealistic.
Yes, diverting the asteroid early is obviously a far better scenario. But there's a big problem here: doing this requires that you actually know about the asteroid well ahead of time, and it requires that you take measures well ahead of time to divert it. This requires a lot of funding. We humans are too cheap and stupid to do this. There's no telling how many asteroids are out there that might collide with us in the next two centuries, because we don't put much effort into looking for them (it seems to be mostly amateur astronomers that look for these, and their equipment isn't all that great). Heck, we even know about one sizable asteroid, named Apophis, that's going to make a close fly-by in 2029, and then depending on exactly how the gravitational interaction goes in that fly-by, might come around again in 2036 for a direct 510 megaton impact, but we aren't doing anything at all about it even though that's only 24 years away. Granted, the impact possibility is still quite low, but if we're wrong, we're looking at some pretty catastrophic effects, either tens of millions dead if it hits land, or who knows how many dead if it hits the ocean and causes a massive tsunami.
So many things wrong with your comically angry post. Some of the main ones:
1) Only asteroid fragments over a certain size make it to the ground. Blow it up enough and yes, it will not make it to the surface. It would add dust, of course, and impart a heating pulse to the surface, but spread out over however long between the furthest-forward pieces from the blast were and the furthest back ones.
2) Deflecting fragments of the asteroid from a collision course is precisely the point of an explosion, whether you're talking a bunch of small pieces that are now missing, or just two halves.
3) A bomb can do more than break up an asteroid; it can also move an asteroid, by radiation pressure, direct or indirect through surface heating.
Sometimes I doubt your commitment to Sparkle Motion.
Or better yet, say that it's just too expensive to bother with, and do nothing. Engage in a public program of portraying any efforts to deflect the asteroid as "socialism". Call this project "Nero".