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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

#41

Post by kbolino »

Tichy wrote: post #18
patio11 wrote: post #16

Earlier quoted context omitted.

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.

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).

Debatable. On the one hand, the farther the projectile is from the planet, the less it needs to be deflected. On the other hand, you have to expend energy to get to the damn thing in the first place.

I suppose the survival of your species renders moot most energy concerns though.

Re: What future space combat would really look like

#42

Post by philwelch »

I don't think space combat is even going to happen. Any combatant with the necessary wealth and technology to develop any space-combat capability is going to have significant terrestrial interests and nuclear weapons already, at which point they're already subject to MAD and won't engage in direct combat anyway. At the very minimum, you would need economically and politically independent Moon/Mars colonies, and even they would be so dependent upon Earth trade that they would either not want to start a war or, even if they did, would have Earthbound allies who are significantly more vulnerable than they are, and no less essential to their survival.

The closest we'll ever get is probably the development of ASAT weapons, and even those aren't likely to see much use.

Re: What future space combat would really look like

#43

Post by quanticle »

Tichy wrote: post #18
patio11 wrote: post #16

Earlier quoted context omitted.

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.

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 .5c, 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 hundred?

Re: What future space combat would really look like

#44

Post by zeteo »

quanticle wrote: post #7

This essay isn't all that realistic. I found this one [1] to have a far more realistic view of what space war would look like. Tl;dr: it's much cheaper and much more effective to lob comets at your enemy's homeworld than it is to fight with ships. [1] http://www.gwern.net/Colder%20Wars

The fighting methods in that essay still require ships (to sneak up into e.g. Kuiper's Belt). In any case, a big, dumb projectile can have its course changed with much less energy than required to fire it. The bigger it is, the earlier it will be detected; and the faster it goes, the smaller the angular deflection needed to miss its target.

Re: What future space combat would really look like

#45

Post by gerggerg »

InclinedPlane wrote: post #38
gerggerg wrote: post #32

Why would space war ships be manned when we're already flying unmanned vehicles on earth? I think we've touched on a reality of intelligent species coexisting in the universe. Space war would consist of staying hidden and probably nothing else. Plus, certainly people would be fighting over the planets or the technology (or maybe the amulet of Endor) so simply throwing comets and obliterating things wouldn't make much…

Speed of light delay could be critical in space battles, especially when you consider that it goes both ways (sensor readings -> brain : decision making -> control signal). The real question is how smart you can make computers, if you can't make them as smart as a human then you need to have a meat-brain somewhere in the middle of the battle. If you can make them that smart then that opens up a whole host of question…

I don't know if as smart as would be valuable against as low powered as. A computer would make decisions instantly, take much less resources, would die less easily, wouldn't get bored, wouldn't forget it's mission, would feel no sympathy, could travel farther, could stay in operation longer, could tactically self destruct without hesitation, would take no salary.

But that being said, I honestly can't think of a reason to ever have a space battle. You either want to blow up a planet or not. If so, you do it from an large distance with a humongous rock. If not, you land on the planet, or fly around their atmosphere and kill them the old fashioned way.

Maybe defensively you chase down an attacker to prevent future attacks? But then all you have is guided missiles and the speed of their ships. Not really a battle.

What I guess I'm saying is I can't ever see there being an attack position other than lets wait until there are no rocks in-between us and them.

Re: What future space combat would really look like

#46

Post by dustingetz »

my takeaway: there will be no space battles, because whichever side has more money will always have vastly superior weapons, and they will take what they want. violence will happen in key strategic plays, like political assassinations. it's not like today's earth-combat where we're all mostly equal and everyone has time to launch their nukes and we all die. this is all assuming that one side doesn't simply exterminate the other like a termite infestation.

Re: What future space combat would really look like

#47

Post by InclinedPlane »

gerggerg wrote: post #45
InclinedPlane wrote: post #38

Earlier quoted context omitted.

Speed of light delay could be critical in space battles, especially when you consider that it goes both ways (sensor readings -> brain : decision making -> control signal). The real question is how smart you can make computers, if you can't make them as smart as a human then you need to have a meat-brain somewhere in the middle of the battle. If you can make them that smart then that opens up a whole host of question…

I don't know if as smart as would be valuable against as low powered as. A computer would make decisions instantly, take much less resources, would die less easily, wouldn't get bored, wouldn't forget it's mission, would feel no sympathy, could travel farther, could stay in operation longer, could tactically self destruct without hesitation, would take no salary. But that being said, I honestly can't think of a reaso…

We already have nuclear weapons on Earth, yet wars still happen. Space is big, incredibly so. And once there are people and industrial infrastructure sprinkled throughout it armed conflicts will probably be inevitable.

Re: What future space combat would really look like

#48

Post by rbanffy »

philwelch wrote: post #42

I don't think space combat is even going to happen. Any combatant with the necessary wealth and technology to develop any space-combat capability is going to have significant terrestrial interests and nuclear weapons already, at which point they're already subject to MAD and won't engage in direct combat anyway. At the very minimum, you would need economically and politically independent Moon/Mars colonies, and even…

> Any combatant with the necessary wealth and technology to develop any space-combat capability is going to have significant terrestrial interests

Imagine a colony that long ago severed its ties with Earth (or whatever other terrestrial body they started from). Living off comets and asteroids seems entirely feasible and it's a much harder to attack/easier to defend set up.

Re: What future space combat would really look like

#49

Post by pilom »

zeteo wrote: post #44
quanticle wrote: post #7

This essay isn't all that realistic. I found this one [1] to have a far more realistic view of what space war would look like. Tl;dr: it's much cheaper and much more effective to lob comets at your enemy's homeworld than it is to fight with ships. [1] http://www.gwern.net/Colder%20Wars

The fighting methods in that essay still require ships (to sneak up into e.g. Kuiper's Belt). In any case, a big, dumb projectile can have its course changed with much less energy than required to fire it. The bigger it is, the earlier it will be detected; and the faster it goes, the smaller the angular deflection needed to miss its target.

While it is true that it should be easy to deflect, it is only easy to deflect if you can detect it. The essay assumes that the projectiles would be pushed to a significant fraction of the speed of light. At that speed there is no time to launch any type of deflection.

Re: What future space combat would really look like

#50

Post by rbanffy »

j_baker wrote: post #33
Avshalom wrote: post #12

Earlier quoted context omitted.

As to 1: It would take years for the light to get there, it would also take several MORE years for the ship to actually get there. The important take away is distance can't be used to hide, there is no "Oh they won't notice us we're still outside the orbit of Pluto."

Well, now we're getting into the theoretical issues. For instance, if we develop wormhole technology, the ship could very well be there before the enemy can see it. Otherwise, I just don't see interstellar space warfare as being that practical if it takes years to launch an attack.

If I could create wormholes at will, I wouldn't traverse the wormhole with the whole ship - just the bombs would suffice.
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