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Should Nuclear Devices Be Kept On Hand To Protect Against Near Earth Objects?
Lasrick writes: Seth Baum ponders whether nuclear devices should be kept on hand for the purpose of destroying near-Earth objects (NEOs) that pose a threat to the planet. Baum acknowledges that "The risk posed by NEOs is not zero, but it is small relative to the risk posed by nuclear weapons." Even so, Baum writes, since the consequences of an NEO hitting the earth would be catastrophic, keeping 10 or 20 nuclear devices available might be a good idea, and would be "insignificant compared to the thousands now held in military arsenals."
Agreed. The question the article poses presupposes that nuclear devices CAN protect against NEOs. Most research in the field answers the question with a resounding "no". The best use of a nuclear weapon against a NEO would be to detonate several, in succession, to slightly alter the course of the NEO or to change its velocity. But as maroberts intimated, this would have to be done at a significant distance from Earth...probably near or past Jupiter's orbit at a minimum.
I'm sorry, but your opinion seems to be wrong.
Actually no it is not.
You do not try and blow up the NEO. You try and deflect it. The idea is that you use the "shaped" nuclear charge design developed for the Orion.
The NEO becomes the pusher plate and you nudge it so that it does not hit the earth.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
1) burn up with.
And where do they burn up? In the atmosphere.
So where does the heat go? Into the atmosphere.
Great, you've just incinerated an entire hemisphere at a mere 600 degrees rather than a single point at a few thousand.
And since heat loss by radiation is proportional to the third power of the temperature, you've just made it take a lot longer to cool off.
Yay.
You forgot:
3) Scatter radioactive fallout with
Still cancer takes longer to kill you that a massive asteroid impact followed by a decade of winter so I suppose it's a win?
So you are going to force China, and Russia to give up the arsenals that they aren't getting rid of? There is really only one way to do that, which would be to destroy them. Nukes are here for the foreseeable future. Let the idea of forcing other people to get rid of something they own out of your mind. The more people that do that, the less likely they will be used.
My favorite idea for getting rid of NEOs is a super powerful laser, that would ablate the surface, and gently nudge the thing off course.
I am sure there are certain scenarios where you could detonate a nuke nearby it, and let the resulting shockwave do the same thing. However the modeling that we have for atmospheric shockwaves is inaccurate, and large object surface will be anything but smooth. Also most celestial objects will be moving much faster than our missiles, so we may not actually have time to intercept them.
I mean no offense to you, OP, however what you purpose isn't possible, that is trimming down the arsenals to only a dozen or so.
A perfect example of this; does Russia still have 152mm nuclear artillery shells? I realize that the were 'destroyed' because of the Start treaty, but I find it very interesting that that is the larger caliber available for the Armata T-14 platform. Which shows another dilemma; can you trust any of the nations that have them to honestly tell you what they have, when first strike capability is so very, very important? They are going to a hell of a-lot of trouble to be able to air-lift 400 tanks to 'anywhere' in the globe (or about 7,000 km) to drop just 400 tanks, which in the scheme of a war with Nato, would be overall fairly useless. Along with having only 80 transports for the entire country is fairly risky. If I were them, that is how I would play it.
As another example, who attempted to 'steal' the nukes via the Minot-Barksdale air base incident? Very few people have the authority to order nukes flown in launch position over the US, in a time of 'peace' (such as that is). Everyone was quietly 'transferred', and no one was court martialed, Which means, that the officers involved in the actual transfer had valid signatures, and they were protecting someone higher up. That's our own country, do you really believe a foreign power is going to be more honest? They won't be, as it isn't the interest of any Government that needs power to enforce its will (i.e., all of them).
Government's are just extensions of the people, and they will behave just like people (i.e. lie to you).
I art more snarky, and terse than thou. I art Slashdot!
A meteorite which does not create a big crater will throw a lot less stuff up into the atmosphere, and will have much less global consequences. Getting a shower of smaller pieces would not be fun, but a single big impact penetrating deep into the crust with equal energy is worse.
RTFA They specifically look at a standoff explosion versus a surface or subsurface explosion and prefer the standoff explosion precisely because they are aware of the possibility of blowing something up with a nuclear weapon. Amazingly enough, the professional rocket scientists at NASA actually considered the consequences of the alternative tactics before making their recommendation
If you blow up an object, I very much doubt that all of its pieces are still going to hit you. Some of them will go in the opposite direction, some will land in a slowly decaying orbit, and very few of them are likely to continue on their existing trajectory, and the few that do will have their kinetic energy reduced.
That's assuming that the nuke actually blows it up. Nukes are FAR less effective in space because there's no atmosphere for the thermal energy to create a big shockwave, and there's no solid ground beneath it to amplify the intended direction of said shockwave.
IMO if you want to blow up an NEO, you'll probably want some kind of kinetic weapon akin to a giant bullet, maybe a space born railgun or something.
Still though, nudging is probably a better approach.
You will be less likely to have a nuclear winter in that scenario, but something that hits with a gigaton of energy in one piece, is still going to release a gigaton, only over a larger area. It may not create a crater, but you'll probably have pretty much all the vegetation (and people) go up in smoke before the fireballs hit the ground. Lighting a continent on fire may be almost as bad as a direct impact. In fact it may be worse.
The US changed from using huge megaton warheads on it's nuclear missiles because you actually get more effect from more, but smaller warheads which impact in a wider area. You're still dropping a few megatons per ICBM, but more surface area is affected.
That's not how military chain-of-command works.
First, you have to assume the guy with the power to give the order to launch is rational. Then, you have to assume that someone exists in the chain of command who does not believe a second strike is survivable. Since Reagan, our foreign policy has been that survival is a possibility.
We have had presidents and very high-ranking Air Force brass who believed the world was destined to end in a biblical apocalypse that would herald the return of Jesus Christ to raise all believers to heaven. Now you're down to trusting the rational decision-making of a low-level grunt who's been stuck below-ground in a silo, watching every day for the launch order to come down. You think they train those guys to be skeptical of the orders they're given?
OK. It's funny that people who will otherwise question everything government does also have such unshakable faith in their government when it comes to A) the military and B) the police.
You are welcome on my lawn.
We could have build a large Orion propulsion ship anytime in the last 40 years. It would probably cost less than an aircraft carrier. A large Orion propulsion ship could get almost anywhere in the inner solar system in a few weeks. And the propulsion system will work just fine to redirect another large mass. Yes, there will be a bunch of fallout damage from the initial take-off, but we can decide where to place it. and the fallout damage from Orion's propulsion is tiny compared to the damage from an asteroid strike.
I have always hoped that there was a secret plan to convert our offensive arsenal into Orion propulsion if the need occurred.