SciFi weapons that would actually work

Cafe Society
1

Full disclosure: I’m currently writing a book (for my own pleasure) that involves space battles. I’m trying to figure out what space combat would be like, what weapons and tactics would actually work by extension of technology or theory we have today. I thought I’d come here and see if any dopers want to let their imaginations run wild in speculation on various SciFi books or movies and what COULD work with both weapons and tactics in space.

From my readings, the Honor Harrington universe weapons seem promissing. I think that missile weapons would be quite effective, especially fired in massive waves. X-ray lasers seem a good weapon. I’m not sure about nukes. It seems to me that tossing nukes (maybe even anti-matter weapons) would pretty much be decisive, especially if you could get them to penetrate the ship. How could you protect against something like that from simply vaporizing your ship?

My thoughts are that even if one could get ships to move at some high fraction of light speed, the ships wouldn’t be able to manuver very well with out killing off the crews. I’m envisioning battles almost like in the age of sail where fleets pretty much either ‘anchor’ themselves and duke it out, or move themselves into position where their vectors bring them into weapons range…or run away if the opposing fleet seems too powerful. Fleets may even have ‘broadside’ armorments if they use projectile weapons or missiles, and perhaps even have ‘load times’ for beam weapons (as capacitors recharge). Finally I’m thinking about unmanned ‘fighters’ that could be real time controlled from ‘carriers’ and could (perhaps) do things that manned ships couldn’t.

Anyway, those are my thoughts right now. What thoughts does anyone else have? What weapons or tactics in popular fiction do you think COULD or WOULD work (and actually be practical in terms of real science)? Go wild and tell me your thoughts. :stuck_out_tongue:

-XT

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Would it. Seems to me nukes are real good at setting things of fire, burning/irradiating people and knocking down buildings. If your ships had a hull a couple meters thick and you could keep the missle from penetrating the surface the explosion would just heat up the outside a bit. Course if the missles did penetrate and exploded inside the hull, then the battle would be over.

I could imagine a battle where the ships try and weaken spots on eachothers hulls with lasers or something in order to get a nuke far enough inside to take out the other ship.

Anyways, I don’t think you could plausibly ignore nuclear tech, which we’ve had since the 50’s, and make a belivable sci-fi story.

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Here’s an idea. The two opposing sides have built such huge ships, with gigantic hulls that are tens of meters thick, that missle weapons can’t penetrate far enough to do damage. As a result, when two ships close to do battle, they each launch boarding parties (robots or real people, whatever floats your boat) with various types of drilling equipment, kinda like Bruce Willis in Armeggedon, the idea being the teams have to drill deep enough into the hull of the enemy ship to place the nukes. Ship to ship combat would then degenerate into basically amphibious assults, with teams on each side trying to zip over, and then hold a spot on the opposing ship long enough to drill deep enough into it to place the bomb.

Would be different anyway.

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True, it would be about penetration. However, what about the change in vector for a rapidly moving ship hit by a sufficiently high yield nuke? Would this cause the crew to black out or even die? I’m thinking of a ship moving at some high percentage of the speed of light suddenly knocked sideways by a 100 megaton explosive (or bigger). Even if you didn’t really damage the hull or the ship, what would be the effect on the crew?

Also, is it possible to create the equivelant of deep space radiation but in a concentrated form? I was watching a program once that described such radiation as a ‘machine gun’ through the body. I suppose that ships in space would have shielding from natural radiation…but what about some weapon (probably nuclear of some sort) that focused radiation with the intent of killing the crew, not the ship (I suppose the X-ray laser would be something like this but more focused).

I agree. I’d say that and kinetic weapons moving at very high velocities would be the real killers. My problem is I’m unsure of the actual effects of nukes on space craft armored for combat.

-XT

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I like the idea of composite armor tens of meters thick, though I suppose a kinetic weapon moving at high fractions of c would penetrate even that (think of a ‘warhead’ made of a super dense metal or composite moving at 50% the speed of light. At 75% the speed of light. I doubt ANYTHING could withstand such a blow intact).

As to your idea of boarding parties, my guess would be you’d have some kind of close in defense system on the hull (just to pick off the incoming missiles if nothing else), so it would be very hard to get small craft in close enough to drop folks off on the hull. Also, you’d probaby have other defense on the hull for this contingency. Think of how hard it would be to drill through some composite armor 10’s of meters thick while under fire. Yikes. :eek:

Still, I think the boarding idea goes along with my current ‘age of sail’ theme so assuming I can work up how the rest of the combat would flow I think I’ll steal that idea. :wink:

-XT

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I doubt boarding parties would work; a small nuke would vaporize any plausible small craft or space armored marines.

Semi - Plausible technologies :

Antimatter bullets fired from mass drivers.

Arrays of lasers that can target and destroy anything unstealthy; they can just keep beaming and beaming as long as necessary. For that matter, you can build them on airless bodies like the Moon.

Clouds of nanotech dust that eat unauthorized vessels that enter them ( best defense : a high velocity that burns it away on impact ).

For really high tech cultures, micro black holes launched at high velocity.

Rather than just space battleships, I’d also think in terms of hordes of small, very stealthy ships or drones armed with weapons that can kill almost anything if they actually hit; hiding and ECM is the best defense.

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I was thinking of a expansion of the metal storm systems currently being looked at for anti-missile defense, but fired at very high velocity. I don’t know if you’d NEED anti-matter bullets (if by that you mean anti-matter in the bullet and not used as propellant for the projectile). I suppose it depends on what speeds we could realistically get projectiles up too. Even a 100 lb/kg projectile moving at .5c would be devastating if it hit a warship.
How plausable are gravity manipulation weapons? Could one use focused gravity or gravitonic effects to propel projectiles? I’ve seen them used in several books and movies (even beam weapons that use gravity effects to tear ships appart), but I don’t know how realistic such a thing would be.

Definitely I think lasers would be used, though they require a lot of power and I doubt you’d be using them in sustained fire mode unless you had a LOT of power to spare. I was thinking of charging capacitors and firing high output lasers for a few seconds before recharging them. Anyone know what a masor or grazor is (not sure if I spelled them right)? I’ve seen mentions of both in SciFi books but never found out exactly what they were…or how realistic they are.

Intersting idea. I’m using nanotech in my book though in a different way. I use it to manufacture in space (in short, set up a nano-nueral network, ‘program’ in a matrix, grab an asteroid and turn them loose…in some time period you will have a ship/station/whatever). Also I’m playing with using nano-tech to ‘disassemble’ a starship and crew, reduce it to component molecules, open a micro-wormhole in the quantum foam to some specific location and ‘beam’ it through, reassembling it on the other side. I suppose the same could work for disassembling an enemy ship and simply not reassembling it (same way the nano-tech I envision disassembles asteroids in space into their component parts).

-XT

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If you can manage to find a copy of David Langford’s War in 2080, I highly recommend you pick up that. It looks at various sci-fi technologies and what would work (so far as our contemporary understanding of physics goes) and what wouldn’t work.

One of the things that he says, which many people find kind of surprising is that if your planning on zero-G combat, probably one of the best weapons you can have at your disposal is a scimitar. It’s a low mass weapon, and no recoil, so you’re less likely to send yourself flying about in unintended directions in combat.

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In the Honor Harrington books, the ships and missiles used in space combat generate high-intensity bands of gravity above and below the ship, and just kinda “fall” between them everywhere they go to get around. The smaller missiles, lacking the space for a nuclear warhead, just use the gravity bands to slice into their targets, usually with rather impressive results.

Masers and Grasers, I think. I want to say a Maser is like a Laser, but using something other than light (I want to say microwaves). In the Honor Harrington books, a Graser is basically a really big laser that uses a shaped high-intensity gravity field as a lens to focus the beam energy through instead of whatever their lasers use.

Also in the Honor Harrington books, nanotech is used from time to time for assassination attempts of varying degrees of complexity.

Something I was thinking you could do is have a cruise missile that is similar in size to a fighter, but instead of carrying weapons, is equipped to ram enemy ships, or perhaps explode in the vicinity of enemy fighter formations, etc.

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I’d also recommened getting ahold of a copy of the Aliens Technical Manual if you an. It’s got a good, if brief, section on space combat including weapons, tactics etc.

"There are three thinsg you must remeber in a space battle. One: he who shoots first wins. two: range determines the shape of the battle. Three: it is hard to radically change your velocity vector in space.

Range determines the shape of the battle for the simple reason that your weapons are optimaed for diffrentranges. To give you an idea about what we mean by range, we consider the liongest range to be the limit of the starships detection range - up to a hundred thousand kilometres."

And so on in that vein. It brings up some interesting and fairly important points. Taht one bour range is fairly typical. If you have large vessels moving in vacuum with futuristic technology then the battle is going to begin well before any human being can even see the enemy. Ships are going to be easy to spot by any number of sensors, including what the manual refres to as ‘starfield array sensors’ that detect shadows or lights moving against the background. And after it’s detected the vessel will be fired upon from a hundred thousand kms back. That makes the idea of Star Wars and Star Trek close combat pretty unlikely in mosty circumstances.

Then we get into all sorts of counter sensor measures, including the deployment of massive blimps designed to register as a starship. Becasue there’s no gravity and no air pressure these become exceptionally cheap and easy to manufacture and deploy. It also means it take smuch longer for an enemy to register a definite target.

My favourite weapon is the deployment of 'orbital minefields". These aren’t explosive mines, they are simply massive, semi-rigid nets many kilometres across that are either placed in orbit or left drifting free in a potential battlefield. The idea being that if a vessel strikes such a net at a speed of even 100, 000 km/hr it’s going to do some serious damage to itself. One potential use for these things is to be deployed behind a vessel that;s being pursued. Since the mines are so hard to see it makes pursuit very risky. Alternatively setting up a few of these well away from you vessel prior to battle makes it harder for the enemy to close range.

The idea of a floating fortress doesn’t sound very feasible to me, for much the same reasons they’ve never been feasible on Earth. First off they will require large amounts of fuel to move an maneuvre, so while they may be harder to damage they will take damage far more often. Armour has always been a compromise between ability to hit, ability to avoid being hit and ability to withstand hits. A floating fortress of this type will take punishment, but it’s ability to dodge or even align itself for firing will be severely impaired.

The second problem, and the one that always limits current weapons, is that a combat vehicle needs to be able to see. A vehicle with a hull hundreds of metres thick will be like a clam getting into a fight with an otter. Sure it’s tough to crack, but it’s effectively blind and moves so slow it can’t possibly escape. The otter simply hammers at it until it cracks. And if you put sensors on the outside of your vessel then you are still going to be just as much a target for nukes as a vessel with a standard hull. The nuke may not crack the hull, but it will burn off all your sensors, leaving you intact but blind and effectively out of combat. And remember that means totally blind. You won’t even have visual capabilities since you are totally encased in metal several metres thick. Lighter and more maneouvrable ships will avoid being hit altogether far more often, and they will then simply be able to float past taking pot shots an an enemy that can’t see them to fire back. Even if they can’t crack the shell they can certainly plug up the engines or attach rockets to pull the vessel off-course.

That then leads us to the possibility of indirect fire. One massive floating fortress that is nothing but a gun platform. It is surrounded by a swarm of fats-moving, cheap fire control vessels, possibly just drones. The drones remains far enough away to avoid getting nuked, and acts as floating eyes for the fortress. Then we get into a Star- Wars type situation, with sensor drones, and combat drones sent out to shoot down the sensor drones, and then combat drones to protect the sensor drones and so forth. The main ship then becomes a combined gun platform and aircraft carrier.

Which I guess demonstrates that it all depends on how you want toplay it. Arms developmentis always an arms race. Every measure always evolves a countermeasure. There are any number of possible solutions if you have sufficient imagination.

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Definitely I’ll look that up…sounds like exactly what I’m looking for. Thanks! :slight_smile:

Except that I envision ‘space marine’ types in powered armor exoskeletons (with some kind of limited propulsion capability), so a simple sword wouldn’t be very effective. Now, maybe an energy sword of some kind (light sabre, rapidly vibrating mono-molecular power sword, plasma in energy field sword, etc) would do the trick. Also, assuming we’d have the power for power armor we’d probably have small enough high energy power sources for person beam weapons of some kind, and they would be reactionless (I assume he was talking about the reactions from projectile weapons being fired in zero-G).

Thats kind of what I thought. I still don’t know how practical such things are…especially the gravity weapons.

Definitely, though in the HH universe thats pretty much what their missiles do (at least they can maneuver realtively freely in avoiding counter fire, though most of them use X-ray lasers I suppose). I’m thinking that missiles though that can accelerate to very high final speeds would hit in the way you describe and transfer some horrendous kinetic energy into the target ship.

-XT

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I’ll definitely have to check that one out as well as it seems exactly what I’m looking for. Thanks!!

Of course stealth might play a role also. In addition, as you said before its hard to change vectors radically, so one could perhaps envision various zones of combat. The heavy ships would engage at extremely long range with guided missile weapons and hammer away at each other, using electronic counter measures and defensive fire. They could also launch on ballistic trajectories small ‘fighter’ craft, perhaps unmanned (that either us AI or perhaps even some kind of remote control like a Predator) that could engage at closer range. Also, once the heavies get into medium range (assuming they live that long) they could engage with beam weapons and perhaps high unguided projectiles (that would be more difficult to ‘shoot down’ due to their lack of guidance, and perhaps stealth materials). I could see even the heaviest ships closing to short ranges…depending on how tough these ships are.

Ah, but this assumes the armor is simply a big hunk of metal. What about some kind of ‘smart metals’? Perhaps laced with nano-tech so that the entire hull becomes a sensor? Damaging any one spot would not disable the entire sensor suit. Or you could have tethered arrays outside the ship…sort of like a submarines ‘tail’. Obviously this would be a target, but the ship could, in theory, have more than one that could be deployed in the event one was taken out. Perhaps the hulls wouldn’t be tens of meters thick, but use various layers of different materials in a composite sort of like modern armors do…layers that can protect against different things even, or even shift their fundamental structures depending on the type of attack (‘smart metals’ again).
Thank everyone for all the thoughts. Keep em coming! This stuff is my bread and butter. :stuck_out_tongue:

-XT

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Yeah, that’s precisely what the manual gets into. The section on space combat is only about 10 pages, but still far too long t post here in detail. It goes into the different ranges of various weapons inclusding missiles, plasma railguns, beam weapons etc.

Well, yeah. If you want to play around with ‘magic’ technology (and you’re a sci fi author, so you can and probably should) then anything becomes possible. But this sort of thing is like the inertia fields in ‘Dune’: it’s an integral part of the plot in its own right and totally changes all other rules. There’s no real way to address what sci-fi weapons would work in reality if you are going to factor in stuff like smart metals and nanotech that don’t exist in relaity. That’s not to say that you shouldn’t introduce that sort of stuff. It’s just that without telling us in advance we can’t really speculate about what might work.

In reality it’s hard to see how even ‘smart metal’ would be able to cope with a nuke. You presumably have sensors capable of registering energy levels equivalent to visible light at the very least, and there is so little energy in most of space that they probably need to be an order of magnitude more sensitive than that. In reality any sensor that sensitive is going to be sensitive to damage. After billions of years of evolution the eyes and ears are still the weak spot for most animals because you can’t have both hardness and sensitivity.

Even if a ship is 10 km long, equivalent to a Star Destroyer, all sensors are going to be suffering, at the very least, from the equivalent of flash blindness from one nuke burst within 5 km. Of course as an author you can simply write in that this problem was overcome, but at that point we are no longer talking about something that will work in reality. You could just as readily write in that there is an energy shield that provides perfect protection from nukes, which is just as believable and still renders nukes obsolete. Once again, there’s nothing wrong with those sorts of plot devices in Sci-Fi, but it renders this discussion somewhat moot.

This is essentially just a more cumbersome method of the indirect fire I mentioned above. It has all the same problems of independent spotter drones (being targetted by enemy fighters etc) but with a lot of other disadvtages, such as limited range from the parent ship, no dodging ability, massive tail that becomes an obvious target for wirecutters etc. Transmissions travel so well in space and flight is so cheap that I can’t see why you would bother to tether your sensors. Far more effective to let them float free. That way they can actively evade attacks targetting them, they can be used to see into blind spots so the enemy can’t come ‘out of the sun’ or over the horizon and they can get far more range away from nukes tagetting the gunship. Keeping them tethered might make it harder to jam the signals (and it might make it easier) but it’s hard to see that being sufficiently advantageous to make it worthwhile. Subs tether their sensors because radio waves won’t travel through water. They need that cable to act as a transmission wire. That’s not an isue in space.

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I was assuming a relatively low velocity, since I was talking about semi-realistic weapons. I was thinking in terms of a simple slug of antimatter; nothing fancy.

Not that plausible; gravity is the weakest fundamental force. In terms of efficiency electromagnetic weapons like lasers ( or kinetic ones ) are much better. Honorverse gets around this because impeller wedges steal energy from hyperspace; they can accelerate so fast because it takes them no energy to do so, beyond establishing the wedge in the first place.

If you use solar power, you have an unending power source; if you use nuclear, you have one that lasts years. I was actually thinking of a book called The Farside Cannon, which involved a field of thousands of solar powered lasers that could destroy anything man made in line of sight in the solar system.

Masers are microwave lasers; grasers are gamma ray lasers. Masers are already here, used for communications and some experimental weapons. Gamma Ray lasers are theoretically possible but not yet real. In scifi, grasers sometimes refers to a gravity laser; I’ve no idea if it’s possible.

With that wormhole technology, you could pop some antimatter onboard an enemy ship and blast it from inside. If the wormhole is stable, you could drop one end into a star and the other on a planet you don’t like.

15

the remake of Battlestar Galactica seems to favor physical projectiles, be it bullets from Vipers and Raiders, nukes from BaseStars and Raiders, shrapnel/flak canisters from the Galactica’s “Mass Driver” cannons, the mechanicals have built-in machine guns, and the Colonial millitary use what appear to be fairly conventional firearms

Farscape’s personal weapons seem feasible, the pulse pistols and rifles fire a superheated blob of Chakkan oil, so even though it loks like a “little…yellow…bolt of light” it’s not a laser/phaser based optical beam weapon, it’s a physical superheated projectile, the Peacekeeper Command Carrier uses “frag cannons” implying some form of physical projectile, the Luxan Qualta Blade/Rifle is feasable in “blademode” but not as feasable in riflemode as it is an energy-based weapon

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Well, I don’t know how ‘magic’ smart metals would be. Seems it would be merely an extension of nano-tech. If one assumes nano-tech is possible then its extrapolation to explore what it COULD do. And the entire hull being a large sensor is really not that far out there.

Also, the composite hull I also proposed (that wouldn’t need to be tens of meters thick) is just an expansion of what we already use in our modern tanks. Perhaps several generations advanced but not really ‘magic’. :slight_smile:

-XT

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Some possibilities from the world of roleplaying games:

In **Traveller: 2300 (A.K.A. “2300 AD”), **starship combat was very like modern submarine warfare, with stealth being the primary defense. Weapons included independent seeker missiles that would try to ferret out the enemy and, when they found a target, would detonate a nuclear device that, in turn, powered a single, massively-powerful X-Ray laser.

Personal weapons included “plasers,” which fired a superheated plasma slug down the path of an integrated laser that heated up the air (sort of extending the barrel all the way to the target).

In Living Steel, one of the main features of the battlefield is powered armor suits made of nanite-laced metal that repairs damage to itself.

Gamma World, while more fantasy than sci-fi, had some neat weapons. Black Ray Guns were essentially portable, directional neutron bombs, that instantly killed living creatures but caused no damage to inorganic objects. Torc Grenades very neatly eliminated all solid matter in their blast radius through a mechanism that was not explained, but could have involved a momentary supression of electromagnetic force or something.

Weapons from Paranoia are best left in Alpha Complex, particularly the Nuclear-Tipped Cone Rifle shell, which had a blast radius of 2000 meters. Unfortunately, the Cone Rifle itself had a maximum range of 1500 meters …

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One possible advantage of having a tether is communications, in that a signal traveling up and down a cable would be harder to jam than a wireless signal. Perhaps a small set of tethered drones could be kept as a reserve for this situation, or, even better, equip the wireless drones with tether-capability in case you need it.

Yeah, IIRC, the only limiting factor for ships using gravity wedges in the Honorverse was how powerful their inertial compensators were. The higher the mass of the ship, the more powerful a compensator was needed to reach any given acceleration (speed only becomes an issue in regards to particle sheilding, in one book, a ship reaches .9c before hitting a piece of dust and exploding instantly)

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An idea that has been touched upon above but I think would play a much larger role is waves of drones. These would be relatively small unmanned craft that can act independently of human intervention but can work together.

For attack, they could be armed with a big laser to cut through hulls (if the armour of a ship is going to be 10m thick, putting lots of tiny holes in it in a vacuum will really annoy whoever is inside), a big warhead that can detonate on impact (or even burrow in then detonate once the drone has clamped to the side of the ship).

For defence, they can sit around in open space with passive sensors to detect enemy ships. When one or a fleet is spotted they could broadcast it’s position, follow it and broadcast the position using low power communications to nearby drones, or simply attack.

Of course the defences to these machines would be drones to seek out and kill other drones.

I don’t see what good a big starship full of humans is going to be to be perfectly honest, if it has to have 10m thick armour just to survive is there any point having it in a battle? I think the most likely scenario will be for drones to fight it out millions of kms away from any humans with the loser being open to attack.

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Technology defines tactics.

The first thing you’ve got to decide is how your ships move around. Are we talking about chemical rockets, ion rockets, fusion rockets, or antimatter rockets? If you’re using rockets, even ones powered by total conversion, your ship is limited to a specific amount of delta-v. Increasing the amount of fuel doesn’t do much to help, since the vast majority of that extra fuel is just going to be used up moving around the extra fuel.

You can calculate how energetic your reaction is, and how much of the ship will be fuel, and therefore calculate the total delta-v of the ship. Even with total conversion, with reaction mass shooting out at 99% of the speed of light this is going to be a much smaller number than you might think. There’s no way to just turn on the engines and constant-boost across the solar system. Ships still have to pay attention to orbits, and a ship’s ability to maneuvar will typically be a small fraction of its total velocity. The crew can’t take accelerations of more than 9 gees for more than a few seconds, and 3 gees for a few hours. And all too soon you’re going to run out of reaction mass. Rockets pretty much have to be unarmored or you’re pissing fuel away.

Now, we can get around this with artificial gravity. With artificial gravity you can have ships accelerate with as many gees as they like and the crew is safe and they have unlimited delta-v. Now you can have ships roaring across the solar system in a few days, turning on a dime, etc etc. But first decide exactly how your anti-gravity works and then determine how your ships will use it.

And if you allow wormholes and spacewarps and such, all bets are off.

Next weapons. Without artificial gravity, you’ve got a few real-world choices. Rocket missiles are feasable, they can accelerate faster than a human can stand, and they don’t have to worry about coming back home. You want to burn your missile’s fuel as quickly as possible and coast most of the way, only leaving a bit of fuel for homing. Remember that the enemy ships can only maneuver a little bit compared to their total velocity…they can take small-scale evasive action, but can’t turn or run away or hide where they’re going to be. The missiles can be equipped with kinetic warheads…hitting even a BB at orbital speeds is going to hurt. Or HE, or cannister (a cloud of BBs), or nukes, or antimatter. No matter what, if a missile hits it’s gonna hurt, since your ship can’t be armored much or it won’t be able to move. A variation on rockets would be guns or rail guns, but they have the same idea…you launch at very high speeds with only a little reserve for maneuver, since by the laws of physics the enemy can’t be very far away from where you predict him to be, even with rockets blasting at 9 gees. Countermeasures could be computer-controlled machineguns or lasers, but hitting a kinetic weapon doesn’t kill it, it just kills the guidance, you still have to dodge it.

Or you could try beam weapons…lasers, microwave lasers, heck any point on the EM spectrum could be a laser. Or particle beam of who knows what…electrons, protons, or some exotic particles traveling at .999c. This means pumping as much energy into the ship as possible, hoping to cook it or burn delicate bits. You can’t have much armor, but mirroring is possible, so is chaff or dust or carbon nanofilments…in Traveller they had defensive sandcasters to foil lasers.

But the real weapon is your sensors…the first side to detect an enemy ship will almost certainly win. One shot, one dead or crippled ship. And a crippled ship is usually dead, since it probably won’t be able to return to a safe base with its remaining delta-v. And you can’t rescue most crippled ships, since a rescue vehicle would have to accelerate to a higher velocity than the cripple, catch up, decellerate to match velocities, transfer surviving crew (you can’t save the crippled ship, since that doubles the mass of the rescue vehicle, or halves the delta-v), then accelerate to put yourself in an orbit to reach a safe base. Even with total-conversion rockets this is very tricky if the other ship was moving at high velocity. And even if your first hit doesn’t kill the enemy ship, if you disable the enemy sensors then he’s blind and can’t return fire.

So your ship is studded with telescopes on all EM wavelengths, plus whatever exotic particle detectors you like, and stealthed as much as possible, although when you use your rockets you’re sending out a huge, “Here I am!” And if you use remote vehicles/probes, they have to communicate with you via EM…radio or laser or some such…those messages could be intercepted or jammed. And EM travels at c, so UAVs halfway across the solar system can’t be directly controlled in real-time.

And of course, you have to ask why ships are fighting. What do they hope to accomplish? Are you fighting for resources? What resources? Asteroids, planets, trade? It seems to me that the ability to destroy ships would vastly outstrip the ability to build and fuel ships. One side or the other is going to win pretty quickly. Of course that means warfare is going to be assymetric…once one side’s ships are knocked out they can go wherever they like, but what do they want? Since nuclear bombs aren’t going to be disinvented, and there are plenty of asteroids that can have their orbits changed to hit any planet or stationary base, anyone that can get into space can destroy any other country on earth, or all of earth, or any planet you care to name. What do you hope to accomplish after you’ve blasted the enemies ships to atoms? How do you stop him from dropping a dinosaur-killer on Earth even after he’s lost?