60m Asteroid currently assigned a .022% chance of hitting Earth.
http://neo.jpl.nasa.gov/risk/2012da14.html
http://rt.com/news/paint-asteroid-earth-nasa-767/
Seems like a good opportunity to bring up existential risks. And A friendly reminder that NASA is in fact pretty damned important.
Thoughts?
It could do a lot of damage if it landed in the right place, but it’s a bit of a stretch to call it an existential risk.
I don’t believe anyone was calling it an existential risk—rather using it as a reminder to people that such existential risks do exist and are not that far beyond what we see here. And, of course, that we can take active measures to oppose such risks and that we are not, in general, taking sufficient measures.
Right; it’s big enough and fast enough (~2.2 MT in impact energy) to ruin someone’s day, but it’s not going to kill ALL of us regardless of where it lands.
...is it wrong that for sheer morbid fascination alone I sort of want to see it hit?
Only if you act on this urge.
I’d also like to see it hit. Most of the Earth is still pretty much empty, so even if it hits the Earth, it will probably end up somewhere where a 2 Megaton burst is relatively unimportant. We can predict where it will hit a long time in advance, so nobody need get hurt. It would be good science, and a media event. For many countries with lots of land it could even be a good foreign exchange earner. And it will encourage governments to stump up the necessary money to map the other asteroids.
Pity it will almost certainly miss. 0.022% isn’t much.
IIRC, the main damage from asteroid impacts is the tidal wave resulting from a probable drop in the ocean, which would cause deaths within an order or two of the Indonesian tsunami in ’04.
Now, that would be really fascinating. I would definitely want to see someone act on that urge.
Challenge accepted.
(Now all I need to do is to review perturbative orbital dynamics, find a way to launch a spacecraft even though NASA said it would take them two years to do so and it is scheduled to be at closest approach next February, and develop a mechanism for changing the albedo of an asteroid with paint. In space.)
Not directly related, but an easier question: Do we currently have the technology to launch projectiles out of Earth’s atmosphere into a path such that, in a year’s time or so, the planet smashes into them from the other direction and sustains significant damage?
(Ignoring questions of targeting specific points, just the question of whether it’s possible to arrange that without the projectiles falling into the sun or just following us eternally without being struck or getting caught in our gravity well too soon… hmm, if we could somehow put it into an opposite orbit then it could hit us very strongly, but in terms of energy… hmmm. Ah, and in the first place there’s the issue that even that probably wouldn’t hit with energy comparable to that of a meteor, though I am not an astrophysicist. In any case, definitely not something to do, but (as noted) morbidly fascinating if it turned out to be fairly easy to pull off. Just the mental image of all the ‘AUGH’ faces… again, not something one would actually want to do. )
Any kinetic energy an object has, it has to get first. If you compare the size of satellites with their respective rocket it looks difficult to make an object of any reasonable mass get any significant speed. You can trick a bit with swing by maneuvers, but as far as I understand no man made object makes any more than a little sound at the atmosphere while entering. You could however poison the planet with a nice substance.
On the other hand it might be possible to use a man made satellite to deflect a bigger object so that it crashes into earth. But please do not try this on your home.
A fair point. On the subject of pulling vast quantities of energy from nowhere, does any one country currently possess the knowledge and materials to build a bomb that detonated on the surface could {split the Earth like a grape}/{smash the Earth like an egg}/{dramatic verb the Earth like a metaphorical noun}?
And yes, not something to try in practice with an inhabited location. Perhaps a computer model, at most… actually, there’s a thought regarding morbid fascination. I wonder what would be necessary to provide a sufficiently-realistic (uninhabited) physical (computer) simulation of a planet’s destruction when the user pulled meteors, momentum, explosives et cetera out of nowhere as it pleased. Even subtle things, like fiddling with orbits and watching the eventual collision and consequences… hm. Presumably/Hopefully someone has already thought of this at some point, and created such a thing.
Can we? Probably not, there don’t seem to be enough fissiles available: http://www.coarsegra.in/?p=95
There’s also scale issues at play—as your bomb gets larger and larger, relatively more of its energy escapes into space and isn’t directed into the ground.
The link in question analyzes the possibility of creating a doomsday weapon that could launch a projectile that would destroy all life on another earth sized planet remotely. That is a far more difficult task than just destroying life on the planet the bomb is on. The limiting factor in question is also fission materials to serve as triggers for the primary explosion in each of hundreds of thousands of shaped thermonuclear explosions. The massive numbers of distinct explosions are needed to progressively accelerate the Orion device but for a single explosion the ration of fissile trigger to fusion material need not be the same.
Mind you the Orion weapon is just intended to obliterate all life. That task becomes comparitively trivial when you aren’t trying to do it across space via projectile. But if Multipartite literally wants to smash the earth into pieces I suspect he is out of luck for now!
He wants something which would crack the planet’s crust; you’re not going to get that with widely dispersed efficient-life-killing thermonuclear strikes (leaving aside the obvious question ‘what do you do about the vents and spores etc’). To do that, you need a lot of energy, whether it’s a kinetic projectile or a fireball & shockwave. A Project Orion kinetic strike would probably be more efficient than a pile of gigaton nukes since each explosion can be smaller and more energy extracted than it.
Where on earth did widely dispersed efficient-life-killing thermonuclear strikes come into it? Multi was considering a bomb (or cluster thereof) at a single location. The closest to ‘dispersion’ was when you brought Orion into it, with it’s chain of bombs spread out over the launch distance.
Or, alternately, it would be overwhelmingly inefficient because the projectile is aimed away from the planet—or at best along the surface of it.
I incidentally dispute your efficiency claim anyway. I’d be willing to bet that if you collect every one of the bombs you were using for your Orion weapon and place them in single location then it would be more capable of slippiting the planet than the projectile would have been. Even if you managed to make it target the earth directly. If necessary you would of course use several years worth of the entire earth’s production of steel (and maybe lead, gold and anything else hard or heavy) and use it to cover the bomb and keep the energy around a tad longer.
Why does it need to be aim along the planet? Use orbital mechanics: Send your spacecraft on an orbit such that it hits the planet it launched from at the fast point of a very long elliptical orbit. Or even just at the far side of the current planet’s orbit, whatever. It can’t be that hard to get an impact at whatever angle you’d prefer with most of the Orion vehicle’s energy, launching direction barely seems to matter.
No particular reason. It’s just that the arbitrary task of planetary self destruction that Multipartite specified happens to be that of destroying the planet with a bomb on the surface. If you were just trying to destroy the planet then doing so from the surface seems like a terrible idea.
(For thoroughness, noting that the other approach was also wondered about a little earlier. Surface action is an alternative to look at if projectile-launching would definitely be ineffective, but if the projectile approach would in fact be better then there’d no reason not to focus on it instead.)
As I already said, the scaling laws mean the larger the bomb, the less efficient it becomes. Piling together 200 bombs just means you get inefficiency and possible fratricide from the explosion themselves or neutron emission. (Looking briefly at my old notes, underwater explosions have an exponent of tonnage raised to 2⁄3 for the resultant overpressure wave.)
If we had some convenient test planets handy I would bet against you when it came to optimal planetary suicide methods.
Orion’s is a great idea for a different task but just not the solution to this problem.
/shrug
I’m the one who has read in detail about basic equational descriptions of nukes by their tonnage, targeting concerns, the engineering involved in going to megatonnage or gigatonnage range, etc. (I wanted to make a nuke simulation game), so you’ll pardon me if I put more weight on my opinion than yours.
And you must pardon me if I find that:
Your reference work pertains to an entirely different problem—one of interstellar planetary destruction.
Your reference work pertains to killing a population not destroying the planet itself.
The limiting factor that you appeal to is the lack of fissile material. This is an artifact of the tactic you have adopted of making many moderately sized nukes. If someone was optimizing the total amount of explosion they could make from a given amount of fission material they quite obviously would change the design. For example they would include a third stage of fusion fuel. Most bombs that been constructed thus far (with the hypothesized exception of Tsar Bomba) have not bothered to do so because, well, what would be the point?
You haven’t even seemed to acknowledge that there is a problem making your projectile effectively destroy the earth when it has been accelerated across the surface of the earth and so is pointing in totally the wrong direction.
Whatever mass of theoretical expertise you may have behind you, you most decidedly haven’t applied it coherently here. To the extent that if you had just made an assertion and appealed to your own authority I may have believed you but given that you explained details that are clearly wrong I have to dismiss it out of hand.
They’re the same thing.
The scale factors don’t refer to killing populations.
The more stages you have, the worse the instabilities become. 3 stages is doable, but any more than that? Seriously questionable.
Is that seriously an objection? Why on earth does it have to be accelerated across the Earth’s surface? You’re being really lazy here in not even thinking of any alternatives.
No they aren’t.
Three is more than sufficient to undermine your proof of concept “not enough fissiles” declaration.
What the? Don’t be absurd. “Bomb on the planet’s surface.” was exactly the problem specification. If I wanted to destroy the earth I would obviously not try to do so with a bomb on the planet’s surface.
Any interstellar method is a fortiori a terrestrial method as well.
In what respect? The Tsar Bomba gives us an estimate on what the third state buys one, let’s be generous roughly an order of magnitude (6mt to 60mt). The analysis I linked concluded that the existing nuclear stockpile was at least 100x too small to power an Orion, so a 10x increase is useful but not enough (and where’s the plutonium for 65k stage threes coming from?). If we go with the link’s world-wide estimate of 300,000 years of production and blindly apply the 10x estimate, that still leaves us 30,000 years short.
And where does the Orion vehicle hit?
(Would an ICBM be excluded as an answer because it enters space?)
It’s a task with entirely different challenges and to which entirely different tactics are optimal. It is just plain not the case that all interstellar methods are a fortiori terrestrial methods—since the very method your declaration of impossibility assumes is sufficiently optimal to rule out any possibility is one that doesn’t work when launched from the surface of the target planet.
The Tsar Bomba was deliberately crippled from it’s original specifications so as to reduce fallout while still being a sufficiently excessive explosion (although this was only on the order of a twofold reduction). Regardless I am almost as willing to accept the Tsar Bomba as the theoretical best (or worst) case for what humankind can do with a three stage thermonuclear device as I am to declare that ‘Little Boy’ the most potent fissile device that humans could make.
Simply taking the calculations used for hypothesizing about Orion weapons and applying them to surface based doomsday device is a gross error. The approach taken and the limiting factors would be entirely different.
This is not to say that I believe we currently have the technology to destroy the planet itself. To the best of my knowledge we do not. I simply reject the notions that an Orion device would be the way to go about it and hence that the fission limitation found when hypothesizing about Orion still applies at the levels calculated. I don’t present an alternate hypothesis that because these limitations no longer apply as calculated that we must be able to do the destruction—that would be reversing stupidity.
Not at the location where the bombs go off—that’s exactly the problem.
I suppose Multi would allow it provided in returns and detonates at or near enough to the surface. My initial speculations about using Orion for self destruction speculated at finding a gravity well sufficient to slingshot it back to us—but that engineering feat strikes me as a tad difficult.
I’ll rephrase it, then: any method planet A can use to attack planet B can also be used by planet A to attack planet A. In the case of an Orion object, some large hyperbolic orbit which intersects the Earth seems possible, but if not, it could always be slowly launched out to whatever distance necessary and turn around.
No doubt that’s part of the explanation, but is it the whole explanation? From one of Wikipedia’s refs:
Another part of the ref mentions those modifications were made due to bitter arguments about whether it would work at all. (A quote from a report to the Soviet politicians says the design allowed for bombs of ‘unlimited power’ - which given the context, is as trustworthy as a $3 bill.)
Reducing the yield and eliminating an entire tamper sounds like something one might do if one is not sure the instabilities have been dealt with. Finally, to quote from one of the rival Soviet bomb-makers:
(Unfortunately he doesn’t say whether the complexity and size were solely an issue for delivery or intrinsic to scaling, but it’s suggestive.)
Yes, it is a gross error. An Orion vehicle is probably more efficient than a giant nuke or set of nukes, so the lower bounds aren’t going to be tight.
That sounds rather a lot more plausible than the story they may prefer to be believed.
Doubtful. Breaking the earth up is hard. The biggest explosion ever made is this one: http://en.wikipedia.org/wiki/Czar_bomb
You’d probably have to use a more powerful kind of rocket than any that currently exists, like a nuclear rocket, to launch enough mass into space for it to cause “significant damage” upon reentry.
I’d love to see it hit the ocean somewhere away from airplane and shipping routes
It’d probably wake something from an ancient slumber.
There’s a serious danger of tidal waves from that size impact (assuming it actually impacted and didn’t do an airburst like Tunguska). So even if it hit an ocean it could be a bad day.
According to Wikipedia, the Japanese tsunami was caused by an Earthquake who’s “surface energy” (which I imagine is what’s relevant for tsunamis) was about 2 orders of magnitude more than the expected 2 megaton impact of this asteroid, so it probably wouldn’t lead to a huge tsunami.
Additionally there’d be a much more obvious and earlier warning than for a “conventional” tsunami, allowing more people to reach safety in time.
Is it funding time for NASA again?