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Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

businessinsider.com

51–60 of 62 posts

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#51
post #27

But why, there are already more than enough ways to kill people. And yet somehow sane and affordable healthcare is out of reach.

This way you can kill a lot of people without irradiating the territory or the atmosphere.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#52
post #22
post #18

Earlier quoted context omitted.

It just needs to be more or less a rod. The exact shape doesn't matter much, so there's not going to be much working it, just melt it into a rod and done. (There are some ceramics that can handle the necessary temperature.) You can also sinter it, it doesn't need to be especially strong, just hold itself together while falling, and sintering can make it strong enough. The strength plays no part at all when it impacts…

> The strength plays no part at all when it impacts. At the energy involved it might as well be a noodle. It just needs to handle the heat and resistance of reentry. So why tungsten, rather than a tungsten skin on a lead bar?

when it impacts. You want your missile to reach the ground in one part, and you want it to have low air resistance, so that most potential energy goes into the kinetic energy at impact, rather than say, heating or melting your projectile or the air.

Also, the density of tungsten is about 75% larger than that of lead. Iridium and osmium are about 15% heavier still, at about twice the density of lead (osmium is heavier, but by only 0.12%)

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#53
post #25
post #16

Earlier quoted context omitted.

I'd imagine at that speed (mach 8) it spends only a few short seconds in the part of the atmosphere that is dense enough to cause it to deviate from wind. Maybe a few metres? The thing I was more curious about is how they drop it from non-geostationary orbit and still have it entering the atmosphere and landing at the right place.

It would need a precise retrograde burn at a precise orbital location. This means it will be slower than surface based nukes and have a highly variable time to target. At a low orbit this could be 90 minutes, at geostationary orbit it could be almost a day, but it will always vary based on the location of the target and the weapons orbital position when the order is issued.

I think they'd just get very strategic about the direction they launch it from the satellite. They mentioned 15 minutes in the article but that would require multiple satellites in the sky. The idea of putting rocketry and guidance systems omboard seems plausible too.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#54
post #14
post #4

There's an economic incentive for the moon base! Since it's so expensive to bring heavy payloads up by rocket we can just mine them on the moon. It surely won't be too long until the US needs to mass-produce the godrods anyway.

From the moon, you don’t need high quality weapons; you can compensate by increasing mass. And that moon base could become independ3nt because of its ability to launch rocks ( https://en.m.wikipedia.org/wiki/The_Moon_Is_a_Harsh_Mistress... )

Independence requires more than the ability to “drop rocks” it requires total self-sufficiency. Without that you’re bombing the people who can kill you just by withholding essentials like food, water, and air. No one is even pretending that a colony on the moon or Mars could be self-sufficient to thst degree with anything like our current technology.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#55
post #33

Earlier quoted context omitted.

> I'm pretty skeptical that the energy dispersed from a tungsten rod impact would be dispersed in a manner similar to a nuclear weapon. You're right, it wouldn't. See below. > the tungsten rod, I would expect, is dumping a lot of it's energy into shattering bedrock as it burrows half a kilometer deep into the earth's crust Yes, that's the point: the expected use for these weapons is to hit hardened targets undergroun…

What's to say it would have the desired terminal effects when it hits the underground bunker, instead of simply piercing the bunker and continuing deeper underground? If the underground bunker is built with bulkheads, would one portion of the bunker getting pierced by a rod necessarily turn people in another section into hamburger meat?

Guessing by lethal shockwaves are from relatively small explosions (like packets of C4), I'm going to go ahead and guess the energy dispersed from this would easily shatter all the concrete of the bunker and instantly kill anything living.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#56
post #53
post #25

Earlier quoted context omitted.

It would need a precise retrograde burn at a precise orbital location. This means it will be slower than surface based nukes and have a highly variable time to target. At a low orbit this could be 90 minutes, at geostationary orbit it could be almost a day, but it will always vary based on the location of the target and the weapons orbital position when the order is issued.

I think they'd just get very strategic about the direction they launch it from the satellite. They mentioned 15 minutes in the article but that would require multiple satellites in the sky. The idea of putting rocketry and guidance systems omboard seems plausible too.

You can't deorbit something just by "dropping" it from a satellite. If you want to target a single "rod" they would need independent onboard guidance and propulsion.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#57

Earlier quoted context omitted.

What's to say it would have the desired terminal effects when it hits the underground bunker, instead of simply piercing the bunker and continuing deeper underground? If the underground bunker is built with bulkheads, would one portion of the bunker getting pierced by a rod necessarily turn people in another section into hamburger meat?

Guessing by lethal shockwaves are from relatively small explosions (like packets of C4), I'm going to go ahead and guess the energy dispersed from this would easily shatter all the concrete of the bunker and instantly kill anything living.

Maybe, but I'm not convinced. With enough velocity, a ping pong ball can blow a clean neat circular hole straight through a ping pong paddle. Fast moving objects can cause extremely localized damage. On the other hand if you shoot a fast at a plastic jug full of water, an incompressible fluid, it will shred the water jug specifically because that water is incompressible. Fill the jug with air or sand and you'll then find that the jug remains intact when you shoot it, save for two bullet-sized holes through both sides.

If the tungsten rod is able to borrow through hundreds of meters of bedrock, it seems to me that's a sufficiently efficient penetrator that it might 'ice pick' straight through the target bunker dumping only a small fraction of it's energy into the bunker, as it then goes deeper through more bedrock.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#58
post #47

Earlier quoted context omitted.

To be fair, coming up with new weapons is a lot simpler than fixing the world's healthcare systems.

In what sense? In the "we have the technology, medicine and money for people to live healthy well into their seventies but we choose to spend it on doomsday machines instead" sense? In the "our armed forces are now so well-equipped and well-funded they would simply take over if we tried to cut funding to reasonable levels" sense? In the "everybody else is an enemy" sense? What a lot of nonsense.

I meant in the "give billions of dollars to weapon manufacturers and they'll keep inventing crazy shit, but you can't even begin to enumerate the number of organizations and agencies you'd have to give funding to in order to effect change in our systemically flawed healthcare status quo" sense.

In other words, it's a complexity problem. It's easy to take money, throw it at a defense contractor, and get weapons out the other end. But to change healthcare, thousands of laws would have to be changed, and hundreds of government agencies would have to change their daily operations. And politicians would use the change to polarize their voter base.

What we need is to educate the younger generations on the benefits of universal healthcare, show them how it's the inevitable way of the future, and eventually they'll get into office and do the hard work of making the necessary changes. It may take generations.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#59
post #29

Earlier quoted context omitted.

The shape matters because you want to maximize the impact speed which means minimizing resistance of reentry. A simple rod will not keep its orientation while falling down, it needs either fins or a different shape.

You actually have to decelerate rapidly, so you warheads fall at a steep angle. Gliding reentry is inaccurate

At which point there’s no reason putting this thing in orbit instead of launching it as a regular ballistic missile.

To hit one target on the ground you are going to need thousands of rods in orbit to ensure that one is available to use on the target. This is necessary because things in orbit will only be able to de-orbit on top of things that are close to their orbital plane.

Re: Air Force 'rods from god' kinetic weapon could hit with nuclear-weapon force

#60
post #25
post #16

Earlier quoted context omitted.

I'd imagine at that speed (mach 8) it spends only a few short seconds in the part of the atmosphere that is dense enough to cause it to deviate from wind. Maybe a few metres? The thing I was more curious about is how they drop it from non-geostationary orbit and still have it entering the atmosphere and landing at the right place.

It would need a precise retrograde burn at a precise orbital location. This means it will be slower than surface based nukes and have a highly variable time to target. At a low orbit this could be 90 minutes, at geostationary orbit it could be almost a day, but it will always vary based on the location of the target and the weapons orbital position when the order is issued.

A better orbit is retrograde solar, just inside or outside the Earth's orbit. With 183 of them in orbit, one would pass by the Earth every day. With a week or so advance notice, aiming would be easy.
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