Because People in power are Stupid: What if we hit it earlier, like way earlier than it's orbital pass- couldn't we nudge it into a different course?

That's always been my take on it.

Moving it by just a tiny degree from far enough, and by the time it get's close, it'll miss by quite a bit.

If anything, the last thing we'd want is a broken to million of pieces cloud of mini asteroids hitting the planet.

We just need to ensure that it's gonna miss the moon and not end up in some sort of gravity pulled boomerang trajectory.

It anything, don't send a bomb, send a very powerful engine to push it into such an angle.

Do the needful: What about super huge poles extending out into space with some rubber bands stretched across them?

Are you the ACME CEO?

JC

TFA: the device would need to be about a billion times stronger than the biggest bomb ever detonated on Earth -- the Soviet Union's 50 megaton hydrogen bomb "Big Ivan" -- in order to save the world the asteroid.

Thank god the article the grammar.

Sylvia_Bandersnatch:
3) Will everyone *please* stop using 'effect' as a verb when they mean 'affect'? 'Effect' is the result after something has been affected.

Ya, I hate when they get it's usage wrong.

theresnothinglft: while a gravity probe is an interesting concept what mass would it take to actually deflect an asteroid. I would expect at least 10% of the asteroid's mass would be enough to deflect it but i don't really know about that part. The thing there though is if we can build a rocket that can launch such a mass into orbit then the same rocket can be attached to the asteroid to deflect it with.

The answer is a VERY tiny mass, so long as you detect it early enough (which you will) and get the probe there. The precision of the trajectory needed to hit a target as tiny (by solar orbit scales) as the Earth is, well, astronomical. The tiniest disturbance to that trajectory will cause a miss by hundreds of thousands of miles.

I always want to scream when I read about some "near miss" by an asteroid that gets within 100,000 miles of Earth -- Earth has a 12000 miles-ish cross section -- I want to play darts for money with these guys -- they think it's a "near miss" if they're within 8 feet of the target.

erewhon: relcec: pretty sure that is what staging is for.

Staging is the sort of thing any thermonuke does - you use a primary to ablate the casing on a Teller-Ulam secondary, compressing the Li6D and an inner plutonium sparkplug until the sparkplug itself fissions, which provides the heat and neutrons to convert the Li6 to tritium and fuse it with the deuterium.

However. You can't make the secondary arbitrarily long or large. Because you end up with Munroe jets due to uneven compression; boundary-layer instabilities are exacerbated by larger secondaries. Also if you make it long enough you end up with "toothpaste squeeze" where you set off one end of it but not the other. You can actually use that to your advantage by artificially inducing it to reduce yield in dial-a-yield secondaries but if you're trying to get the whole thing to go it's sort of limiting.

I've never seen a multiple-secondary weapon. I imagine that tiny inconsistencies in the assemblies would cause one to go off ahead of the others and you'd have a less than spectacular yield from the last one(s) to go.


the czar bomba was a three stage they think. Link
the b41 was a three stage one of ours. only weighed five tons too. just a few hundred pounds more than the one dropped on hiroshima. we had 500 of them at one time.
I think adding stages may make it more efficient because the later stages can transform more mass do to higher pressure and energy. http://en.wikipedia.org/wiki/B41_nuclear_bomb

"The Mk 41 was an example of a fission-fusion-fusion-fission type thermonuclear weapon, or tertiary stage bomb. The additional tertiary fusion stage, compressed by a previous fusion stage, could be used to make a bomb with yields as large as desired (see Tsar Bomba, a Soviet three-stage bomb and the highest-yield nuclear weapon ever built or tested)".

so I'm not sure there is a limit in the number of stages. of course it would only be needed if you wanted to render the earth uninhabitable, so there is a very practical limiter on its design and development.

relcec: pretty sure that is what staging is for.

Staging is the sort of thing any thermonuke does - you use a primary to ablate the casing on a Teller-Ulam secondary, compressing the Li6D and an inner plutonium sparkplug until the sparkplug itself fissions, which provides the heat and neutrons to convert the Li6 to tritium and fuse it with the deuterium.

However. You can't make the secondary arbitrarily long or large. Because you end up with Munroe jets due to uneven compression; boundary-layer instabilities are exacerbated by larger secondaries. Also if you make it long enough you end up with "toothpaste squeeze" where you set off one end of it but not the other. You can actually use that to your advantage by artificially inducing it to reduce yield in dial-a-yield secondaries but if you're trying to get the whole thing to go it's sort of limiting.

I've never seen a multiple-secondary weapon. I imagine that tiny inconsistencies in the assemblies would cause one to go off ahead of the others and you'd have a less than spectacular yield from the last one(s) to go.

Vaneshi: Quantum Apostrophe: FarkedOver: Antimatter bomb.

Sure, now all we need to do is wait for a good special on antimatter at Home Depot.

Go ask CERN, it is a by product of particle accelerators. Unless you snag it in a magnetic field it'll just pop back out of existence but they do have rather strong magnets there. They can probably supply you with the 'magnetic bottles' needed to transport it back home as well.

We've already ferried anti-particles around on airplanes, it's a faff and I'm sure the expensive 'bottle' was guarded less some baggage handler steal it but beyond that not a problem.

I didn't say getting your hands on a stable vial of AM would be cheap now did I?

Having more than a handful of particles, now, that's the trick. The more you have, the stronger the bottle has to be exponentially. They're usually charged - mostly CERN makes positrons - and the more you have the more they repel each other. It is a problem.

here is a nice impact effects calculator Link
It includes major effects to the earth, energy released ect... or such as this....fun....
Your Inputs:

Distance from Impact: 100.00 km ( = 62.10 miles )
Projectile diameter: 100.00 km ( = 62.10 miles )
Projectile Density: 1000 kg/m3
Impact Velocity: 9000.00 km per second ( = 5590.00 miles per second ) (Your chosen velocity is higher than the maximum for an object orbiting the sun)
Impact Angle: 12 degrees
Target Density: 2750 kg/m3
Target Type: Crystalline Rock
Energy:

Energy before atmospheric entry: 2.12 x 1031 Joules = 5.07 x 1015 MegaTons TNT
The average interval between impacts of this size is longer than the Earth's age.
Such impacts could only occur during the accumulation of the Earth, between 4.5 and 4 billion years ago.
Major Global Changes:

The Earth is not strongly disturbed by the impact and loses negligible mass.
3.56 percent of the Earth is melted
The impact does not make a noticeable change in the tilt of Earth's axis (Depending on the direction and location of impact, the collision may cause a change in the length of the day of up to 6 minutes.
The impact does not shift the Earth's orbit noticeably.

The All-Powerful Atheismo: Of course the asteroid in that "movie" was ridiculously oversized.

A more realistic mile-wide asteroid would devastate the planet yet would be pretty easily vaporized with a direct nuke hit of appropriate size.

You couldn't vaporize a mile diameter chunk of rock all that easily. You'd need about 100MT for igneous rock. Maybe a bit more. Nickel-iron, that I don't have rule-of-thumb calculators for.

No shiat...isn't this old news?

All we need to do is find a blind black guy to reverse the polarity and modify the deflector dish to utilize the warp engines.

relcec: zedster: is there a practical limit to how large we could make a nuke? I understand the limit for mounting it on a rocket, but if you remove that and set out to make a nuclear landmine, how big could we go?

no limit. hydrogen bombs increase their output by essentially just dumping on more H to the fire.

It's not that simple. Scaling up presents issues that are non-trivial. Mostly around instability in high compressions and timing.

21-37-42: Those are the the questions I wish they had focused on:

Assuming the mass is x, and the speed towards the earth is y, how much thrust would you have to apply (and at what point) to move the trajectory to a safe range? How big would the "engine" need to be? How would you "catch up" to the asteroid to place the engine?


I know...

What about some sort of solar sail?

What about a series of detonations so to create a series of multiple waves that would cause a growing increase by each blast?

What about having a projected blast, using a rocket with a shield to push the wave so to increase it's strength by means of a parabolic effect?

Without an atmosphere, the blast of a bomb would be far from the same effectiveness as on a planet, which is why I consider that something that would provide thrust would be more effective.

no plan to deal with asteroids would involve trying to blow up the asteroid by drilling a bomb or bombs into an asteroid. Deflection is the best way to deal with asteroids. Though the idea of a gravity probe was interesting. An object launched from Earth with enough mass to pull the asteroid with it into deep space.

zedster: is there a practical limit to how large we could make a nuke? I understand the limit for mounting it on a rocket, but if you remove that and set out to make a nuclear landmine, how big could we go?

There are limits to practicality with a two stage weapon design. Not so much inherent in the physics, but in the implementation.

The smaller you can make the secondary, physically, the more even the compression you can get. The longer it is, the more likely you're going to get some funky boundary instability that'll turn your nice symmetric squeeze into some funky Munroe effect fizzle. I'd guess, too, that you'd eventually hit some propagation time limit causing a toothpaste-squeeze failure even with the primary's x-rays doing the illumination of your HDPE.

I dunno, maybe you could make a different design than the ones we use altogether that might work better, but if you need one device to blow up the asteroid that has to be a teraton yield or something, then you've got a lot of design work to do.

(tongue in cheek) it would be easier to just use Proteus on it.

This About That: You guys are missing the point. THE WORLD NEEDS A BIGGER BOMB!

Even bigger than Disney's John Carter of Mars?

Push the Moon in front of it. Geez, do I have to think of EVERYTHING?