Constraints for "realistic" space battles

Could you deploy a physical shield of say relatively thin tinfoil (say what's available at the local grocery) out 100 meters away from your hull?

Would it be effective?

What would be the problems with deploying such a "shield"?

FOTSGreg said:

Could you deploy a physical shield of say relatively thin tinfoil (say what's available at the local grocery) out 100 meters away from your hull?

Click to expand...

Since you wouldn't connect it to your hull you can put it at any distance you want.

Would it be effective?

Click to expand...

Well, the effect would be that any incoming projectiles get vaporized when they hit the shield. If that would be enough to spread a 0,2-0,6c projectile so thin it wouldn't cause damage at a 100m distance? No-one knows. Space agencies are only just researching high-speed impacts at the (comparably) minuscule velocities of orbital collisions and the like. And it turns out they work completely different than collisions do at normal weapon speeds. For example there appears to be a rule that the penetration depth of a projectile decreases if you increase the kinetic energy without increasing the momentum. (i.e. making a projectile of the same weight faster makes it penetrate less deep.)
But at relativistic velocity? Heck if anyone can tell. The energies involved should actually cause fusion if any fusable elements are used in the projectile or object hit. (Though that doesn't add significant energy)

What would be the problems with deploying such a "shield"?

Click to expand...

Biggest problem is that if you make the shield very light and fragile you can't accelerate it. So it only works when you're accelerating away from the attacker in a straight line. or not accelerating at all. If you want to make it sturdy enough to keep up with the ship's acceleration it needs to be stiff enough for that, which means a significantly heavier shield.
The point of using a spinning disc is actually that you can use extremely thin material and the centrifugal force from the spinning will keep it straight.

Lhun said:

Generating plasma is easy, holding it a bit harder. But what i'm not quite seeing here is the benefit of doing that. I know of the current "plasma shield" missile defence plans, but those aren't really plasma "shields". It's a laser that creates small plasma explosions in the path of a missile to make it tumble and crash.

Click to expand...

No, these shields weren't for missile defenses. They were literally a field of plasma held in a magnetic field. Hot plasmas tend to disintegrate matter, cold plasmas are only really effective against EM radiation.

As for the benefit, it seems that a cold plasma will be your defense against light-based weaponry (the stuff that you can't detect until it's hitting you). As for the benefits of hot plasma, really it's only been used against conventional weapons (which are useless at the ranges we're talking about here). The level of energy you'd need to usefully disrupt a ballistic weapon traveling at .1c is so high that I'd think the plasma would be more dangerous to the ship that the projectile.

efkelley said:

No, these shields weren't for missile defenses. They were literally a field of plasma held in a magnetic field. Hot plasmas tend to disintegrate matter, cold plasmas are only really effective against EM radiation.

As for the benefit, it seems that a cold plasma will be your defense against light-based weaponry (the stuff that you can't detect until it's hitting you). As for the benefits of hot plasma, really it's only been used against conventional weapons (which are useless at the ranges we're talking about here). The level of energy you'd need to usefully disrupt a ballistic weapon traveling at .1c is so high that I'd think the plasma would be more dangerous to the ship that the projectile.

Click to expand...

Well, that's where i don't see how it's supposed to work. Against EM weapons, ok, if it is opaque for the respective wavelength, it could absorb the energy. Provided it's dense enough. Though i don't really see why you'd need plasma for that.
Incoming projectiles though will not be influenced by plasma to any relevant degree. Unless they're relativistic, at those speeds, projectiles get vaporized when they hit anything that's not a vacuum.

At what point does "reality" get in the way of enjoyment. In order to really enjoy sci-ri/space battles you need to suspend some disbelief. Some sci-fi staples just seem "accepted" like various types of faster than light technologies. They never seem to be "propulsion" but more like dimensional shifts or a hyperspace setup. There are theories that support the potential for this. My biggest issue with that is that it's always too easy. Nobody seems to notice the transitions.

I just scanned through the posts, so I apologize if I missed something.

I personally like how Jack Campbell created space battles in the Lost Fleet series. He creates enough limitations to make things seem more plausible.

A couple of things I'm trying to incorporate. Using fighters, if the fighter near you explodes, you won't be knocked around by a shock wave/concussion (debris maybe).
Lasers are primarily used to drain enemy shields and cut up enemy fighters. Nothing blows up because a laser hit it.
Ships approaching one another are not always oriented the exact same way. This is space, not the ocean. The enemy ship could be upside down.

Lhun said:

Well, that's where i don't see how it's supposed to work. Against EM weapons, ok, if it is opaque for the respective wavelength, it could absorb the energy. Provided it's dense enough. Though i don't really see why you'd need plasma for that.
Incoming projectiles though will not be influenced by plasma to any relevant degree. Unless they're relativistic, at those speeds, projectiles get vaporized when they hit anything that's not a vacuum.

Click to expand...

Is it conceivable that the magnetic field and plasma could create something like an EMP that would effectively disarm a missile if not destroy it? Perhaps it could force a detonation?

What type of warheads would a missle have to have? Conventional concussion explosions wouldn't do any good in a vaccum.

rmgil04, I get annoyed when I start to hear the "swish" or the "swoosh" of the ship moving through space nd the "zap" of the lasers blasting gaping holes in the enemy (gigajoules or gigawatts of energy output don't just fizzle and dissipate into vacuum - it actually goes someplace, usually downrange in the direction it was fired).

I get annoyed when ships are shooting at each other within visual range and nobody seems to notice that they have weapons which could have been fired from astronomical units away.

I get annoyed when writers forget about light speed lag for messages and communications.

I get annoyed when I read a battle which is essentially a rehash of some WW2 naval battle (particularly Midway) with just the setting changed.

I get particularly annoyed when the story is supposed to be about some great war and the whole thing boils down to a single battle which never really gets fought out before the reader because the writer got sidetracked discussing what this or that uninvolved character happened to be doing at the time.

Worst annoying book in this genre - Midway Between
Worst annoying series in this genre - Honor Harrington

Actually, Midway Between was also a series, but I couldn't get halfway through the first book and only a few pages into the second.

FOTSGreg said:

<snip>
Worst annoying series in this genre - Honor Harrington
<snip>

Click to expand...

Heh. And that series is so much worse in other departments. Most notably Idiot Plot. Noone, for five hundred years ever thought of using missile pods? Seriously? Even though missile pods (well, without the actual pods) are the most sensible way to start missiles in space?

rmgil04 said:

Is it conceivable that the magnetic field and plasma could create something like an EMP that would effectively disarm a missile if not destroy it? Perhaps it could force a detonation?

Click to expand...

Seems quite unlikely. If you want to use an EMP to burn out a missile, there are easier ways to do that.

What type of warheads would a missle have to have? Conventional concussion explosions wouldn't do any good in a vaccum.

Click to expand...

Nuclear or none. A fast missile doesn't need a warhead, a slow missile needs at least a nuclear bomb as a warhead.

rmgil04 said:

At what point does "reality" get in the way of enjoyment. In order to really enjoy sci-ri/space battles you need to suspend some disbelief.

Click to expand...

I've seen this argument a lot, but frankly, it's quite silly. Is a story about the battle of Agincourt less exciting than the story about the battle at Helm's Deep because it's not merely realistic, it's real?
Realism is a question of how much thought a writer is willing to put into planning out a battle, there is nothing stopping anyone from writing an exciting description of the battle. And if it's planned out realistically, there's a much less chance of it seeming plain stupid in the end.

<snip>My biggest issue with that is that it's always too easy. Nobody seems to notice the transitions.

Click to expand...

What does too easy mean? It's phlebotinum either way, there's no set rules it has to follow except the ones the inventor (hopefully) sets down.

A couple of things I'm trying to incorporate. Using fighters, if the fighter near you explodes, you won't be knocked around by a shock wave/concussion (debris maybe).

Click to expand...

Shrapnel from explosions is much more dangerous in space, since there's no friction slowing it down. If ships are packed tightly enough (which is a function that can be solved given the input of ship size and explosive force) a single exploding ship could set off a chain reaction.
Space fighters though, are never realistic.

Lasers are primarily used to drain enemy shields and cut up enemy fighters. Nothing blows up because a laser hit it.

Click to expand...

Depends on a laser. Any usefully powerful laser will violently vaporize whatever it hits. Which means you get an explosion even if you hit water. If it's a relatively thin laser drilling a hole in a large ship, it wouldn't look too different from a hit by an armour piercing projectile, but if it's a 1m laser, hitting a 5m long vehicle, expect a big explosion.

Ships approaching one another are not always oriented the exact same way. This is space, not the ocean. The enemy ship could be upside down.

Click to expand...

True, but if you include realistic distances, this would be hardly noticeable.

FOTSGreg said:

rmgil04, I get annoyed when I start to hear the "swish" or the "swoosh" of the ship moving through space nd the "zap" of the lasers blasting gaping holes in the enemy (gigajoules or gigawatts of energy output don't just fizzle and dissipate into vacuum - it actually goes someplace, usually downrange in the direction it was fired).

I get annoyed when ships are shooting at each other within visual range and nobody seems to notice that they have weapons which could have been fired from astronomical units away.

I get annoyed when writers forget about light speed lag for messages and communications.

Click to expand...

BTW, you forgot that ships don't need wings to bank and turn in space.

You should read the Lost Fleet series.

I admit that the book I'm writing has gunners in control of weapons, but they only use manual firing on fighters, not larger ships. In my story, lasers are used primarily to weaken shields, or against fighters (weaker armor). Also, laser impacts don't create explosions.

Lasers always would though, IF they're powerful enough to be weaponized.

Any powerful laser on impact is going to cause a material to vaporize, and that vaporization can be extremely violent. Basically it can work just like putting a chunk of explosive on the outside of ship. Should the laser actually be powerful, it would certainly cause explosions, as cubic meters of metal were almost instantly vaporized. In fact the shockwave from the explosion would be the most likely cause of the killing of a starship by laser, since it might be violent enough to split the hull open and cause a ton of damage to the ship's internals.

I just finished The Lost Fleet: Dauntless the other day. I am informed by a reliable source that the book boils down to 'hardcore officer porn'. Suffice to say I found it enjoyable despite that fact.

Realistic weapons, propulsion, and combat. Simple-ish characters, but meh, the story is very straightforward and definitely feels like the beginning of an extended series. I expect the characterization will improve as the series goes on.

All in all, I'd recommend it.

Heh, I didn't forget - when I start to hear the "swish" and "swoosh", that almost always involves wings. I almost always lose it when the Enterprise "rises from the depths" to torpedo Khan's ship in ST:TWOK with that darned-near stupid shark movie music playing in the background...

FOTSGreg said:

I almost always lose it when the Enterprise "rises from the depths" to torpedo Khan's ship in ST:TWOK with that darned-near stupid shark movie music playing in the background...

Click to expand...

Actually, I liked the entire battle scene in the nebula since the Enterprise uses the z-axis to its advantage twice. So many movies seem to have space battles only using two dimensions, it's ridiculous.

rmgil04 said:

Actually, I liked the entire battle scene in the nebula since the Enterprise uses the z-axis to its advantage twice. So many movies seem to have space battles only using two dimensions, it's ridiculous.

Click to expand...

Well, the scene certainly was an impressive demonstration on how to lampshade a cliché and at the same time totally screw that up by still clinging to it. Really using the third dimension would have been firing from straight "down". Not getting on the imaginary 2D plane again like a surfacing submarine.

Lhun said:

Well, the scene certainly was an impressive demonstration on how to lampshade a cliché and at the same time totally screw that up by still clinging to it. Really using the third dimension would have been firing from straight "down". Not getting on the imaginary 2D plane again like a surfacing submarine.

Click to expand...

And yet, at the same time it was an awesome visual, and an entertaining finish. I fear that, if given the same opportunity to make scads of cash, I shall succumb to the entertaining over the realistic. Here's hoping I can combine the two without too much pandering either way.

efkelley said:

And yet, at the same time it was an awesome visual, and an entertaining finish. I fear that, if given the same opportunity to make scads of cash, I shall succumb to the entertaining over the realistic. Here's hoping I can combine the two without too much pandering either way.

Click to expand...

I've said it before, and i'll say it again: the supposed trade-off between realistic and being entertaining is bullshit. If realistic meant less entertaining, historical fiction wouldn't exist. The only real trade-off is between realism and the author being a lazy bum who either didn't want to do the work, or just didn't care.

Lhun said:

I've said it before, and i'll say it again: the supposed trade-off between realistic and being entertaining is bullshit. If realistic meant less entertaining, historical fiction wouldn't exist. The only real trade-off is between realism and the author being a lazy bum who either didn't want to do the work, or just didn't care.

Click to expand...

Being lazy is having galaxy-spanning supernovae, midichlorians, and dropping some heavy deus ex to finish out your series. It's not having battling starships visually see each other in a movie. Especially not for a franchise that's always done it that way. In that regard, it's not bullshit at all.

Would upping the realism really improve the writing? Would it help tell the story? Or would it just add an extra layer of difficulty?

efkelley said:

Being lazy is having galaxy-spanning supernovae, midichlorians, and dropping some heavy deus ex to finish out your series. It's not having battling starships visually see each other in a movie. Especially not for a franchise that's always done it that way. In that regard, it's not bullshit at all.

Click to expand...

Just to go with the Kirk example again. Why didn't he shoot straight "up" when he got the chance? That would have improved the scene a lot, it would have shown that Kirk really did use the third dimension. Khan wouldh ave still looked like a total idiot, making Kirk look, by extension, like a marginally less total idiot, but it would have been a vast improvement over the scene as it was done. When i have a headdesk moment in a film (well, without the desk) because the authors did something unbelievably stupid that could have been done better with ten more seconds of thought put into it and no other trade-offs, it kinda ruins a film you know?

Would upping the realism really improve the writing? Would it help tell the story? Or would it just add an extra layer of difficulty?

Click to expand...

Usually, it adds another layer of believability. There will be less need to suspend disbelief. Which means it will be easier to get away with unrealism in the story where it is really needed, instead of where it saves the author some time.

One of the problems with "accuracy" and realism in space combat is that combat will happen over a period of hours, days, months, or years and the actual "action" will be extraordinarily short and violent.

It is very difficult to described a battle that unfolds over a period of several hours to several days in any excitingly realistic way without sounding like an encyclopedia.

However, with tht said, Larry Niven does it effectively in Protector and Niven/Pournelle do it effectively in The Mote In God's Eye and The Gripping Hand.