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What future space combat would really look like

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Re: What future space combat would really look like

#131

Post by weavejester »

sliverstorm wrote: post #129
ohyes wrote: post #88

Space combat seems pointless to me. What exactly would they be fighting over? Presumably you want to reach space for resources, so asteroids, planets and moons with minerals, stuff like that. You might also want planets/asteroids/moons that are 'good' for colonization (easily terra formed or already life sustaining). You probably wouldn't see many fights where you are firing at the resource itself. No one with the mo…

You can argue this over in your head a lot, but it's really quite simple in my mind. If we assume space travel becomes relatively easy (that is to say it is used for more than initial colonization) there will be interstellar commerce. If there is unprotected commerce, there will be pirates. Any time there are pirates, protection will develop. Let us call these peace-keepers the Navy. If you engage in commerce and you…

I think you're looking at this with a 20th century viewpoint. There doesn't seem like there'd be a lot of physical matter that an advanced civilisation might want to pirate. Perhaps some form of exotic matter, like a black hole, might fit the bill, but that would be particularly hard to steal because everyone could see where you were taking it.

Re: What future space combat would really look like

#132

Post by sliverstorm »

weavejester wrote: post #131
sliverstorm wrote: post #129

Earlier quoted context omitted.

You can argue this over in your head a lot, but it's really quite simple in my mind. If we assume space travel becomes relatively easy (that is to say it is used for more than initial colonization) there will be interstellar commerce. If there is unprotected commerce, there will be pirates. Any time there are pirates, protection will develop. Let us call these peace-keepers the Navy. If you engage in commerce and you…

I think you're looking at this with a 20th century viewpoint. There doesn't seem like there'd be a lot of physical matter that an advanced civilisation might want to pirate. Perhaps some form of exotic matter, like a black hole, might fit the bill, but that would be particularly hard to steal because everyone could see where you were taking it.

Until you can fabricate matter in your MrFusion6000, material resources in some form or another will continue to be valuable.

Once you CAN fabricate, Einstein tells us you will need a TON of energy to do so. So, even if that day comes, you will still need to acquire energy.

Re: What future space combat would really look like

#133

Post by zeteo »

tuppy wrote: post #102
zeteo wrote: post #86

Earlier quoted context omitted.

>I fully expect AI to advance sufficiently in the next 20 years Yes, people have been expecting AI to become human-like within 20 years for the past 6 decades. http://en.wikipedia.org/wiki/History_of_artificial_intellige... ("Researchers expressed an intense optimism in private and in print, predicting that a fully intelligent machine would be built in less than 20 years")

Huh, why do you require human-like AI to control a bunch of high-velocity objects, calculate intercepts, and release other high-velocity objects on those intercepts? The only human-level decision that needs to be made is simply confirming the object is a target and should be attacked.

Most people haven't served in the military, but have you ever played a war game? Deciding where to move the weapons platforms and which objects are targets for what is the very essence of fighting a successful battle.

Re: What future space combat would really look like

#134

Post by zeteo »

amalcon wrote: post #118
zeteo wrote: post #109

Earlier quoted context omitted.

>Almost all of those things were actually decided by the officers commanding the tank / plane battalions You'd be surprised: http://en.wikipedia.org/wiki/Battle_of_Villers-Bocage#Mornin...

It's an interesting read, but that scenario could only occur due to imperfect information. With nearly-perfect information (like what would be available in space), the German defenders would have been mobilized ahead of time, and it would have been a straightforward battle.

Read the entire section... the point is about what Wittman did with a single tank and no orders from his superiors. Yes, he had radio on that tank.

Re: What future space combat would really look like

#135

Post by PotatoEngineer »

sp332 wrote: post #84
andrewflnr wrote: post #59

Earlier quoted context omitted.

It'll start breaking into little blobs, though, which will have less and less power.

It doesn't matter. As long as each "blob" is heavy enough to resist deflection by the wind, the same total mass will impact at about the same speed. The only downside I can see is that the blobs might hit at slightly different times, which would reduce the instantaneous force on the target. But I think it would transfer the same total energy.

The same total energy would be transferred, but it would be spread out over a larger area. If the area is sufficiently large, then all you've done is raise the temperature of Germany by one degree for a while.

(Still, there are plenty of configurations that make good kinetic-kill weapons with a manageable amount of re-entry heat. Think large rods with good amounts of mass and small cross-sections. This is an engineering problem, not a show-stopper.)

Re: What future space combat would really look like

#136

Post by Locke1689 »

ordinary wrote: post #121
Locke1689 wrote: post #111

Earlier quoted context omitted.

All of those things have mathematically optimal solutions given known information. It should be trivial to solve the system.

That does not follow. See TSP.

It doesn't follow in every case, but here the calculations are things like missile ranges, acceleration values, maximum speed, etc. These all seem to be rather simple Newtonian calculations.

Basically the problem dilutes down to: plot an intercept course, fire weapons, rinse, repeat.

Re: What future space combat would really look like

#137

Post by weavejester »

sliverstorm wrote: post #132
weavejester wrote: post #131

Earlier quoted context omitted.

I think you're looking at this with a 20th century viewpoint. There doesn't seem like there'd be a lot of physical matter that an advanced civilisation might want to pirate. Perhaps some form of exotic matter, like a black hole, might fit the bill, but that would be particularly hard to steal because everyone could see where you were taking it.

Until you can fabricate matter in your MrFusion6000, material resources in some form or another will continue to be valuable. Once you CAN fabricate, Einstein tells us you will need a TON of energy to do so. So, even if that day comes, you will still need to acquire energy.

Sure, but even today, raw material resources tend not to be the sort of things criminals target directly. You rarely get thieves trying to steal lumber, or iron ore, for example, because they have a low price-to-weight ratio.

Re: What future space combat would really look like

#138

Post by berntb »

Would it be feasible to use a nuclear device as a shotgun?

That is, most of the kinetic energy of the bomb is directed (like discussions for the bombs in the Orion project). The bomb would be optimised to send tungsten bullets off at X km/s.

Then put that as the payload of a missile.

Edit: Fragmentation bombs was discussed in the second page of the article. Hmm... this would need a very tight spread of the heavy pellets, which is probably not possible with a nuclear weapon?

Edit 2: Add a 2nd level of explosive drive to the fragments? They disperse a bit (to make them hard targets) but know where the target will be and when. More like submunitions, I guess.

Edit 3: Rail guns to send (small) kinetic missiles at a high initial speed? These could potentially run in stealth mode for quite some time, before doing final course corrections.

Re: What future space combat would really look like

#139

Post by makmanalp »

patio11 wrote: post #16
makmanalp wrote: post #9

Earlier quoted context omitted.

Ender's game spoiler alert! Hope it doesn't ruin it for anyone else ... (grumble.) Anyway, how the heck does one lob a comet? If throwing one was so easy, why wouldn't they just throw it right back at you?

Physics. Attacker gets arbitrary mass (reactant, etc) and time to accelerate. Defender needs same mass/time to decelerate... after discovering the attack. Note that you could literally prep an attack for millennia which would be discovered a matter of hours prior to ending a civilization. Physics makes for sucky narratives. Good thing it also makes for a vast, dead, boring universe.

Well, since you're going to skirt around how the acceleration actually happens, I'm just going to counter with: The defender also has arbitrary time to defend. Couldn't you "store up" a defense over time somehow? Maybe have a counter-projectile orbiting really fast that can be brought out of orbit to hit the incoming one? Or, I know we don't have energy shields, but with the amount of assumption going on in this whole article, I may as well assume we do ...

Re: What future space combat would really look like

#140

Post by nialo »

quanticle wrote: post #43
Tichy wrote: post #18

Earlier quoted context omitted.

I don't think you would try to slow down approaching meteorites to zero speed, only deflect them a little so that they miss the planet. The further away you catch it, the less energy it takes (I assume, didn't do the maths).

It depends on the momentum of the asteroid. If I've accelerated an asteroid up to .5 c , then even if you discover the attack years ahead of time you might still not have the energy to deflect the asteroid by enough to save your planet. You also have to remember that the attacker can launch multiple simultaneous asteroids. You might have enough nukes to deflect one asteroid. Do you have enough to deflect ten? A hundr…

Momentum doesn't really work this way. The only things that change the difficulty of deflecting something are it's mass, and the remaining time to impact.

Having a lot of momentum doesn't change how much force is required to give something a given acceleration until relativistic effects start to matter.

(I guess distance also makes it harder, because you need to travel further to start deflection, but that's not really a momentum thing)

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