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

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21–30 of 62 posts

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

#21
If this has "nuclear weapon force", then the rocket used to launch it also contains that much energy.

A quick bit of match says the space shuttle energy is about 1 kiloton of TNT equivalent. That's a pretty small bomb.

Maybe the new launch systems are more powerful.

Although it seems simpler to just fly a rocket full of fuel at the target.

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

#22
post #18

Earlier quoted context omitted.

That price per ton doesn't include making it in the desired shape, though, right? Tungsten is very tough to work with, so I imagine that'd add significantly to the price, though I've no idea how much.

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?

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

#23
I'm pretty skeptical that the energy dispersed from a tungsten rod impact would be dispersed in a manner similar to a nuclear weapon. That is to say, while they may both be just as energetic, the nuclear bomb might be dumping most of it's energy into thermal radiation while 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, ultimately that energy is dispersed as heat, the rocks pierced by the rod would get hotter, but instead of the thermal energy being emitted in one horrible microsecond in the atmosphere above the target, it would be dispersed over a longer time period and over a larger area straight into rock.

That's just my intuition. I don't think these would actually be as effective as the raw energy values might suggest.

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

#24
post #21

If this has "nuclear weapon force", then the rocket used to launch it also contains that much energy. A quick bit of match says the space shuttle energy is about 1 kiloton of TNT equivalent. That's a pretty small bomb. Maybe the new launch systems are more powerful. Although it seems simpler to just fly a rocket full of fuel at the target.

With a series of rocket launches, bringing multiple boosters up to the rod, you could raise it to a higher orbit incrementally than a single rocket would permit. But this would be very expensive and I'm skeptical of the practical value of this sort of weapon in the first place, even if we assume the rod is given equivalent energy.

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

#25
post #16
post #7

How accurate can it be - or does it only work when there is almost no wind? Also, isn't there a maximum velocity based on air drag - if so, can something similar not be dropped from a plane?

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.

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

#26
post #18

Earlier quoted context omitted.

That price per ton doesn't include making it in the desired shape, though, right? Tungsten is very tough to work with, so I imagine that'd add significantly to the price, though I've no idea how much.

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 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.

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

#28

Pretty soon we’ll just dropping small meteors. Farming them might not be cheap, but we’re not going to run out of them.

Always have been curious about bringing outerspace stuff to earth.

Lets say we learn to mine asteroids, wouldnt the extra weight added to earth affect its orbital mechanics in anyway?

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

#29
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 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

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

#30

Earlier quoted context omitted.

"During the Vietnam War, the US used what it called "Lazy Dog" bombs. " Sure, they got the idea from the GI Joe movies /s

Not the op, but just wanted to note various technologies in the past have been inspired by fiction: https://screenrant.com/star-trek-real-life-gadgets/ It’s a symbiotic relationship at times. Eg Computers became a thing, fiction ran with it and made up hand held tablet computers, Tricorders, universal translators etc, which materially (not always exclusively) influence future technology designs and directions. Today…

Are you sure it's not because they are the obvious things?
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