Ammo For Space Combat

[Gtrof]

Hey as I have been watching BSG on scfi, I been wondering somthing. What kind of projectile do you want for a railgun type weapon? Since you don't need to worry about traveling through air, wouldn't a sphere type shell like a cannon ball be best?

[Rickshaw]

If air is not a consideration, then a cube would be the easiest to store, pack and handle.

 

If armour penetration is required, then I'd suggest a cone.

 

If maximum volume is required, then a sphere.

[Stevely]

Big shotgun like shells full of spheres made out of tungsten or DU or something similarly dense and hard. And lots of delta V.

[UN-Interested Observer]

If maximum volume is required, then a sphere.

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I've always had an affinity for two spheres linked by a length of chain:)

[Guest aevans]

Conical design is not necessary for penetration a rail gun velocities. Behavior at the point of impact has more to do with fluid dynamics than classical mechanics.

 

Cylinders probably work better than spheres in railguns, and are almost as easy to handle with automated machinery.

[Mk 1]

I've always had an affinity for two spheres linked by a length of chain:)

 

There is sense to this. But why stop at only two spheres?

 

Or why use spheres at all?

 

An "X" of wire, if encountered at sufficient velocity, could be expected to do great damage. It would also have a fairly wide "capture" area. But perhaps a more complex shape, like a square of wire, or an asterisk-shaped wire, would give higher probabilities of striking what an "X" would pass as a near miss.

 

The key difference in space is that you can accelerate the same mass to the same velocity almost regardless of its density or shape. (There are some complications in HOW you accelerate a large area mesh evenly, but presume for a moment that those are accounted for).

 

So what would we expect the difference in damage to be between being struck by a 1cm diameter sphere of 10g mass travelling at 50,000kph, versus a 5m x 5m mesh of wire with 10g total mass travelling at that same velocity?

 

I would expect that only a small portion of the total area of a space combat ship would actually be life-support chambers. A much larger portion of the ship would be propulsion and navigation, and an even larger portion would be fuel storage (or solar arrays) and sensors. It is harder and harder to pay the penalty for armor as you go from the small "inhabited" parts to the wide open "gathering" parts.

 

Even IF you could some how armor the core of the ship, a strike by a 10g mesh would probably be a crippling blow. A single 1cm spere would have a much larger probability of missing critical systems.

 

-Mark 1

[Josh]

You could easily adapt a continuous rod type design. More over wouldn't it be possible to have a pancake shaped ballute 'slap' into the target? Anyway, cylinders seem best as solid shot if its necessary, and most likely ships will not be armored to any significant degree anyway so solid projectiles would likely not even be necessary.

[Ssnake]

About which engagement ranges are we talking - a few thousand meters? A few thousand kilometers? Under a light second? Under five light seconds?

 

At some point, ray guns are going to gain a lot of attractiveness since you can't outmaneuver them. Or one might want to resort to missile guidance if rays don't cut it.

Speaking of reaction times, what accelerations can our space ships perform?

 

The desired armament will depend a lot on the agility of the target, and the reaction times (detection or suspect of weapon release ... impact). A comparatively slow missile with a nuclear warhead could be preferrable to a railgun under certain conditions (e.g. we find out that ray guns are impractical for other reasons).

[Guest aevans]

About which engagement ranges are we talking - a few thousand meters? A few thousand kilometers? Under a light second? Under five light seconds?

 

At some point, ray guns are going to gain a lot of attractiveness since you can't outmaneuver them. Or one might want to resort to missile guidance if rays don't cut it.

Speaking of reaction times, what accelerations can our space ships perform?

 

The desired armament will depend a lot on the agility of the target, and the reaction times (detection or suspect of weapon release ... impact). A comparatively slow missile with a nuclear warhead could be preferrable to a railgun under certain conditions (e.g. we find out that ray guns are impractical for other reasons).

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Ray guns a five -- or even one -- light seconds? Did they teach you about the inverse square law in physics class?

[pluto77189]

Hey as I have been watching BSG on scfi, I been wondering somthing. What kind of projectile do you want for a railgun type weapon? Since you don't need to worry about traveling through air, wouldn't a sphere type shell like a cannon ball be best?

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Depends on what you're shotting with. A railgun would probably need some sort of irregular shaped projectile, for the rails. I'm guessing long rod cylinder or square cross section rod with integrated(no need to be a discarding sabot) rail contacts.

 

A coil gun projectile would probably be a cylinder, maximum volume for any given caliber.

 

For high velocity shotgun type weapons, you go for squared shot, round ones waste space.

 

weapons will be very effective in space. Unless we get massive, meters think sci-fi starship armor, any impact will be devastating, so bundles of rods, or shotgun type projectiles will be more effective.

 

Even with our current weapons tech, I bet we humans could take down any alien starship in the galaxy. The problem is getting them in space.

 

Once we get our weapons in space, I bet the aliens are going to start getting nervous about us... hehe.

[Josh]

Depends on what you're shotting with.  A railgun would probably need some sort of irregular shaped projectile, for the rails.  I'm guessing long rod cylinder or square cross section rod with integrated(no need to be a discarding sabot) rail contacts. 

 

A coil gun projectile would probably be a cylinder, maximum volume for any given caliber. 

 

For high velocity shotgun type weapons, you go for squared shot, round ones waste space. 

 

weapons will be very effective in space.  Unless we get massive, meters think sci-fi starship armor, any impact will be devastating, so bundles of rods, or shotgun type projectiles will be more effective. 

 

Even with our current weapons tech, I bet we humans could take down any alien starship in the galaxy.  The problem is getting them in space. 

 

Once we get our weapons in space,  I bet the aliens are going to start getting nervous about us... hehe.

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Heh...given the simplicity of weapons technology to kill a star ship or even to destroy the enviroment of a planet, you have to think 1). the defender gets a huge advantage baring some incredible FTL tech and 2). it really pays to kill a society in its infant state rather than hope it won't be hostile when it reaches the stars. There is no reason to think a ship entering our system would be friendly.

[Ssnake]

Ray guns a five -- or even one -- light seconds? Did they teach you about the inverse square law in physics class?

Sure. But we're talking about science fiction here anyways, so it's quite acceptable to assume either and abundancy of energy or lasers with a very, very good focus. Since we don't suffer from atmospheric dispersion in space, I wouldn't rule them out right away.

 

But OK, let's forget death rays for a moment. What's your suggestion how to handle movement prediction for engagement distances in the realm of light seconds?

How do you actually ensure, say, at least a 20% hit likelihood per projectile?

 

This discussion is somewhat futile because nobody has clearly defined the grounds of our nice little speculation here. We don't know what kind of spaceships we're talking, what propulsion systems and energy sources they're supposed to have (and hence their agility), and we haven't defined the engagement distances. How are we come to a valid conclusion under these circumstances?

Narrow down the vast, open spaces of possible technical solutions so that we can come up with a promising design instead of a discussion out of very, very thin air.

[Guest aevans]

Sure. But we're talking about science fiction here anyways, so it's quite acceptable to assume either and abundancy of energy or lasers with a very, very good focus. Since we don't suffer from atmospheric dispersion in space, I wouldn't rule them out right away.

 

But OK, let's forget death rays for a moment. What's your suggestion how to handle movement prediction for engagement distances in the realm of light seconds?

How do you actually ensure, say, at least a 20% hit likelihood per projectile?

 

This discussion is somewhat futile because nobody has clearly defined the grounds of our nice little speculation here. We don't know what kind of spaceships we're talking, what propulsion systems and energy sources they're supposed to have (and hence their agility), and we haven't defined the engagement distances. How are we come to a valid conclusion under these circumstances?

Narrow down the vast, open spaces of possible technical solutions so that we can come up with a promising design instead of a discussion out of very, very thin air.

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I think I stated some time back on a similar thread that guided missiles -- possibly even automated drones w/ self-defense capabilities -- would be necessary for long range work. Guns (either projectile or radiation) would make sense at short ranges.

[Smitty]

I think I stated some time back on a similar thread that guided missiles -- possibly even automated drones w/ self-defense capabilities -- would be necessary for long range work. Guns (either projectile or radiation) would make sense at short ranges.

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I would think that just about any non-DE weapon (railgun or missile) would need an autonomously-guided projectile to have a remote chance of hitting a maneuvering target at light-second ranges.

 

I would also think that a high delta-V missile would be preferable to a railgun projectile as it would complicate direct countermeasures.

 

However, the problem for either would be fast-response DE CIWS-style systems, which could either destroy inbounds, or disrupt their sensors.

[UN-Interested Observer]

I would think that just about any non-DE weapon (railgun or missile) would need an autonomously-guided projectile to have a remote chance of hitting a maneuvering target at light-second ranges.

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So it would be missiles and what? If you shoot missles, and they shoot missiles, don't you need an particle weapon or a ray gun or kinetic energy weapon to shoot down the incoming missiles?

 

Just for note, it was surprising how often warships used their secondary weapons on each other. In theory they should not have needed, but they did.

 

Has anyone watched that show 'The Outer Limits'? I believe one episode had 2 space armadas (cold-war inspired) ready to do battle, and the author had put a lot of thought into it. Each armada formed a long line abreast, and they raced towards each other, where they would fire their missiles as soon as in range. It caused me to think, there would be a lot of time to kill between spotting the enemy and engaging - in this show there was just enough to defuse the situation;)

[Ssnake]

If the target is a spaceship limited to Hohmann transfers, it would be almost impossible for it to outmaneuver even long range shots (provided that you can fire the railgun with accuracy, and lots of it). Say, a stationary base on the moon with almost unlimited supply of energy and a railgun battery. It could fire a couple hundred thousand projectiles in all the months that a spaceship approaching from Mars or Venus would need to reach the Moon, and chances are that even a single hit of a ten gram particle at 20 kilometers per hour would perforate the entire spaceship. So even if the likelihood is down to one out of thousand, such a spacecraft would be dead meat. Or it wiggles and evades all projectiles, but the doesn't have fuel left to actually land anywhere, drifting into space to return in a couple decades, eventually ending as a meteorite.

 

At orbital speeds, a shovel of sand is all you need to take out anything short of a flying mountain.

 

It might be enough to threaten the target with it, and force it to change course so that it simply cannot approach its destination.

 

A prerequisite for space combat is an almost unlimited supply of energy and reaction mass for the spaceship, requiring a technology that we don't know, or nuclear reactors to power a huge battey of ion drives (but then the mass of that spaceship whould be so huge that its agility, again, would be pretty lame).

[Guest aevans]

So it would be missiles and what? If you shoot missles, and they shoot missiles, don't you need an particle weapon or a ray gun or kinetic energy weapon to shoot down the incoming missiles?

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Of course you need close defense weapons -- that's what the guns are for.

 

Just for note, it was surprising how often warships used their secondary weapons on each other. In theory they should not have needed, but they did.

An unlikely situation in space combat over interplanetary distances. Also, it is important to note that secondary weapon engagements were the stuff of bad weather and/or darkness in pre through early radar days. Once radar was fully understood and trusted, capital ships never got close enough for their secondaries to matter. Also note that there is no darkness or bad weather in space. Planets or satellites could come between adversaries, who might get close enough to use their guns on each other if the followed similar orbits, but this would be a very special case.

 

Has anyone watched that show 'The Outer Limits'? I believe one episode had 2 space armadas (cold-war inspired) ready to do battle, and the author had put a lot of thought into it. Each armada formed a long line abreast, and they raced towards each other, where they would fire their missiles as soon as in range. It caused me to think, there would be a lot of time to kill between spotting the enemy and engaging - in this show there was just enough to defuse the situation;)

 

Ridiculously written episode. "Range" in space combat has to do with relative motion and the energy to overcome it, not absolute distance.

[Guest aevans]

If the target is a spaceship limited to Hohmann transfers, it would be almost impossible for it to outmaneuver even long range shots (provided that you can fire the railgun with accuracy, and lots of it). Say, a stationary base on the moon with almost unlimited supply of energy and a railgun battery. It could fire a couple hundred thousand projectiles in all the months that a spaceship approaching from Mars or Venus would need to reach the Moon, and chances are that even a single hit of a ten gram particle at 20 kilometers per hour would perforate the entire spaceship. So even if the likelihood is down to one out of thousand, such a spacecraft would be dead meat. Or it wiggles and evades all projectiles, but the doesn't have fuel left to actually land anywhere, drifting into space to return in a couple decades, eventually ending as a meteorite.

 

At orbital speeds, a shovel of sand is all you need to take out anything short of a flying mountain.

 

It might be enough to threaten the target with it, and force it to change course so that it simply cannot approach its destination.

 

A prerequisite for space combat is an almost unlimited supply of energy and reaction mass for the spaceship, requiring a technology that we don't know, or nuclear reactors to power a huge battey of ion drives (but then the mass of that spaceship whould be so huge that its agility, again, would be pretty lame).

140784[/snapback]

 

Or you do functional decomposition of the problem. Hit the defensive battery with a rock or two (it is sitting still on the surface of a body with known orbital parameters) then come in with your assault force.

[Smitty]

If the target is a spaceship limited to Hohmann transfers, it would be almost impossible for it to outmaneuver even long range shots (provided that you can fire the railgun with accuracy, and lots of it). Say, a stationary base on the moon with almost unlimited supply of energy and a railgun battery. It could fire a couple hundred thousand projectiles in all the months that a spaceship approaching from Mars or Venus would need to reach the Moon, and chances are that even a single hit of a ten gram particle at 20 kilometers per hour would perforate the entire spaceship. So even if the likelihood is down to one out of thousand, such a spacecraft would be dead meat. Or it wiggles and evades all projectiles, but the doesn't have fuel left to actually land anywhere, drifting into space to return in a couple decades, eventually ending as a meteorite.

 

140784[/snapback]

 

So, the counter to this that immediately comes to mind is for the ship to not approach the moon or planet at all. It simply has to nudge enough large Oort cloud objects towards the moon/planet until they overwhelm the defenses and pulverize the opposition. It could even attach various types of countermeasures and maneuvering thrusters to each of them to make them harder targets.

 

Throwing sand at a ship might work, but throwing it at a large sequence of inert planetoids or comets is something else entirely..

[Mk 1]

I can't see much utility in close-in defense systems ... at least not as we understand them within a CIWS-like model.

 

You have a missile coming at you at some significant relative velocity. Choose your favorite number, it doesn't really matter. But let's say 50,000kph just for an example.

 

You shoot it with your CIWS-like device. Perhaps it is a directed energy weapon of some form (laser, particle-beam, anything with light-speed and good accuracy). Perhaps it is an automatic projectile-thrower of some form (gun, rail-gun, spit-wad tube, whatever).

 

What is the best possible effect you will have on the incoming projectile? Is there any means by which you can turn it aside? Can you somehow diminish its mass?

 

There is no "shooting it down" in space. There is no "down" to "shoot it". If it breaks up, most of the pieces are still coming your way. If you manage to detonate it, most of the fragments are still coming your way. If you somehow manage to "vaporize" it, most of the "vapors" are still coming your way. You can manage to make it spread its mass over a larger part of the area you are trying to protect, so the damage may be more widespread but less extreme in any one place. But that's about it.

 

As to maneuvering targets, and guided projectiles ... yeah right. As others have mentioned, the amount of energy you must expend to perform maneuvers in space is quite high. There are no aerodynamic effects to aid you, its all done by thrust. It is your velocity that provides the lethality in your projectile. Every bit of thrust your projectile uses to change its trajectory is thrust that is not used for added velocity. Every bit of added velocity requires even more thrust to have any meaningful effect on trajectory. If you want a dangerous projectile, you are going to have very little ability to change its trajectory.

 

But the targets maneuverability issue looks even worse. The targets that will be most worth defending will be those with the greatest mass. But more mass means much more energy, in the form of thrust, will be needed to get any meaningful velocity. More velocity (with more mass) will mean even MORE thrust will be needed for any meaningful ability to change your trajectory. And ... you need to reserve at least HALF of your potential thrust for counter-thrust (slowing down), or you can't use your mass for any useful purpose (you just go floating off into unknown orbits or out into deep space).

 

So I would expect that "shotgun" style shooting would dominate. Tighter patterns with greater precision for fixed-location targets. Wider patterns, in three dimensions, for moving targets.

 

Maybe a few self-guided projectiles to round out your mix. But not too many. Their utility will be lower.

 

The "shotgun" style shots will be taken relatively soon after sighting the enemy, quite regardless of the distances involved. Courses of travel will be predictable enough (if they are going to be a threat to Earth, or to a moon base, they have to come on a predictable course from where you first see them). Computer calculations will take place quickly enough.

 

"Cap'n, enemy vessel spotted crossing the demilitarized bubble near Pluto."

"I want a 3 Sigma pattern. Feed it in to the fire-control comput.."

"DONE, sir, firing solution rea.."

"FIRE!"

 

This would be followed by a prolonged period in which each side makes peace with its own maker(s), sending various energy-beam communications home to loved ones, as all will know the unavoidable doom which awaits them.

 

The one contrary consideration would be sensor and counter-sensor technologies, and stealth. It is hard to predict the variety of thrusting techniques, active and passive sensing techniques, sensor-defeating materials, etc. that might be deployed. Will active sensors be so easily observed and targetted from extreme range that they become more of a risk than they are worth? Will thrusting missiles be so easy to detect that only non-maneuvering passive projectiles will be used? Will passive projectiles be too easily detected through passive means by blocking the known/mapped background of stars? Will fly-by unguided trajectories be chosed to minimize perceived threats, with massive thrusting late-course corrections (or even directed explosively-forged projectiles) to give lethal trajectories with minimal reaction times?

 

Sensing and stealth/counter-sensing technologies will probably be more important ultimately than weapons and counter-weapons technologies. A fist full of rocks at 50,000 kph is dangerous enough. The key factor on the defense would be the ability to disguise the locations of your high-value resources while maintaining the highest levels of sensing capabilities. On the attack it would b the ability to launch your attack without it being detected, or if detected without it being correctly interpreted.

 

I would predict that as generations of systems might evolve, the clear trend will be towards destructive power greatly surpassing defensive power. But shooting first may well have little meaning, as the time delay between shooting and hitting will be great enough to allow counter-strikes.

 

It may be such a dangerous environment that cold-war style balances-of-terror are the natural state of space-faring civilizations.

 

-Mark 1

[Lentzner]

Nice post Mk1. You bring up some good points.

 

I'm thinking that space combat will be closest to modern sub combat. A lot of sneaking around with the best stealth and best sensors being the deciding factor. Space is not unlike the Ocean, just a hell of a lot bigger.

 

One thing to take into account is that while manuevering is expensive, coasting is free. If you approach a target head on with no significant star behind you and have some sort of radiation absorbtive coating so you don't reflect any sunlight, how will they be able to see you? If you're clever with how you use the gravity wells you could in and out of a system, comet style, without even turning on your engines.

 

Using a laser is not the giveaway you might think, either. A well columnated light will be invisible to anyone not being hit by it. It does not leave a light trail like in sci-fi movies. If your laser is powerful enough to destroy your target before it can tell others where it came from you could attack with relative impunity. It doesn't matter how many light seconds it takes to get there since they won't know it's coming until it hits.

 

You could also soft launch your missiles from a great distance and let them manuever under very low power for a while. Some sort of gas bleed propulsion, while not very efficient, would be very hard to detect at any decent range. Given enough time they could be far, far away before you activated them. Laser based communication would ensure that the enemy didn't pick up your activation signal.

 

I see a very slow paced and drawn out engagement where death comes quickly and without warning. I think actual hit rates could be quite low as there'd be a lot of shooting at ghosts.

 

Matt

[Ssnake]

One of the best fiction about space combat is to be read in (once again) Larry Niven's "Protector" where combat occurs between six space ships at low relativistic speeds in the vicinity of a neutron star, over a period of several months.

 

Likewise, Robert Heinlein and others wrote a whole library about combat in space within realistic restrictions (except that they usually didn't foresee the trends of computer miniaturization and progresses made in signal intelligence).

[Guest aevans]

Mk 1,

 

Questions:

 

Why do you assume that a combatant will have the energy to blanket space with projectiles, but not the enrgy to sense and dodge them?

 

Why are defensive weapons useless, when it is possible to get defensive kill and then dodge debris (if necessary, nobody says you have to wait until the enemy missile is on a final intercept course)?

[Rickshaw]

One of the best fiction about space combat is to be read in (once again) Larry Niven's "Protector" where combat occurs between six space ships at low relativistic speeds in the vicinity of a neutron star, over a period of several months.

 

Likewise, Robert Heinlein and others wrote a whole library about combat in space within realistic restrictions (except that they usually didn't foresee the trends of computer miniaturization and progresses made in signal intelligence).

140908[/snapback]

 

 

I'd heartily recommend C.J.Cherryh's science fiction works. She writes a pretty good tale and her space combat takes into account relativistic effects in I believe quite a realistic way.

[Mk 1]

Why do you assume that a combatant will have the energy to blanket space with projectiles, but not the enrgy to sense and dodge them?

 

I own a 12 gauge shotgun. With 2 drams of gunpowder, I have enough energy to project a dozen BB-sized projectiles, each one of which can cause lethal damage to a human. In space, barring proximity to a significant source of gravity, they would have a lethal range of hundreds of millions of kilometers.

 

It does not take a lot of energy to launch small masses to lethal velocities. It takes even less energy if the launching platform is itself travelling at a significant closing velocity to its target.

 

I think there WOULD be energy for active sensing. I think it would have a high priority. The problem is that potential targets can almost always sense the emitter at a greater distance, and with greater precision, than the emitter can sense the echo from the targets. The original emission is always stronger and always has less "noise" than the echo.

 

So lighting up an active sensor would be inviting a precision strike. This is similar to current naval warfare doctrine. Stay passive as long as you dare. Don't light your active sensors until you are highly confident that you are in a lethal firing position. Then launch it all as fast as you can, and pray REAL HARD while you scoot away at best possible speed.

 

Passive sensors would be very important. It is very hard to judge what they would be sensing. Various EM emmissions for certain, but most adversaries would likely try real hard to be "EM quiet". So what else do you sense? If you can't sense emmitted information, you try to sense missing information that should be present from background noise. What kinds of noise? EM from stars (light, X-rays, whatever), gravity effects (we don't know how to "sense" gravity yet, but we can measure its by-products, such as minute variances in the evident locations of stars), reflected EM from really BRIGHT emmitters (like local stars).

 

As to dodging -- I just really doubt the return on invested energy. You're travelling through space at 25,000 kph, in a 40,000 kg craft. How many kgs of fuel will it take to change your trajectory by 1 degree? I don't know the math, but I am expecting it would be quite a bit. And ... what difference does it make for you to change your trajectory by only 1 degree? How long will it take you to be 5 km from your original course? How much easier is it for your opponant to put out a 10km-wide "pattern" to ensure you are still hit? To put out a 100km-wide patter? And ... if you change your course, how do you get BACK on the course you originally wanted? It will take you again as much energy to make a new course that converges upon your original destination, or worse yet twice again as much energy to return to your original course (if you wanted the course, rather than the destination).

 

Why are defensive weapons useless, when it is possible to get defensive kill and then dodge debris (if necessary, nobody says you have to wait until the enemy missile is on a final intercept course)?

 

Why would your opponant shoot only one projectile at you? Why would they be coming on anything but an intercept course? The current "pop-up" maneuver of many naval missiles would probably not be very common, except as a deceptive ruse (see my prior post's comment about non-threatening trajectories).

 

Consider your challenge. You and I have equal shooting skills, equal shooting technologies. I shoot at you with my shotgun. You try to shoot each and every one of my shotgun pellets from the sky. Good luck!

 

If you have the technology and resources to shoot all of my pellets from the sky, it will always cost me less to put them up, than it costs you to shoot them down, both in energy and in technology.

 

And the real clincher is that, in space, all I have to do is hit you with the debris anyways. When we have a closing trajectory of 50,000 kph, or 200,000kph, or perhaps much more, a single BB is likely to do terrible damage to a 40,000 kg space craft. Split that BB into 16 tiny pieces, and it is STILL just as lethal. Liquifiy it and it is STILL just as lethal. Vaporize it and it is STILL just as lethal. You have no likely means of reducing its mass, only of affecting the organization of its mass. But it does not need to be coherent. It only needs to be mass at velocity.

 

That is why I say why even use balls/BBs at all? Even balls with chains? Just use wires. A mesh of wire (in any of many conceivable patterns) travelling at high sub-relativistic speeds, would be a terribly dangerous projectile. And its mass could be such that a mesh many kms across, in three dimensions, could be accelerated to very high speeds for a relatively low cost in energy.

 

Imagine a sphere, 5km in diameter, constructed of hair-thin wires of randomly selected ductile material (it does not need to be metal), in a mesh with 1 meter intervals between nodes, travelling on a trajectory that causes it to converge with you at a closing speed of 50,000kph. You are very clever, and you sense it from 500,000 km away. What are you going to shoot at it to stop it? How much energy will it take for you to dodge it? Guess what? I didn't send one. I sent a spherical cloud of 25 of them. Their total mass was one-hundredth the mass of your space craft. It took me only a fraction of the energy to get them to lethal speed that you might spend to dodge them. And I've always got another 25 of them I can send your way.

 

This is kind of a fun what-if. Not sure I'm on the right track, but given my understanding of space physics, it seems to me that meshes would be the best projectiles.

 

-Mark 1