So in the sci.fi world I am currently building, I am trying for a fairly technical approach to space combat. Movement is cumbersome and you're strafing more so than performing maneuvers that aren't really possible in a vacuum. Larger ships are much slower since you're fully reliant on thrust to turn and you probably won't want to have a main engine facing in every direction (though that is an interesting thought to play with...) Space combat is a fairly long-distance affair (compared to modern ground/naval combat anyway), get too close to the target you're blasting and you risk collision with debris at critical velocities, etc.

It is also important to note that I have "shields", in the form of unstable Alcubierre warp bubbles which, rather than producing a coherent bubble, just creates a field of unstable/oscillating spacetime around your ship whose tidal forces can, at least to a certain extent, bend lasers and tear apart projectiles. It's a bit random though so of course ships carry varying degrees of armor as an extra layer of defense.

In such a setting, I am wondering what kind of weaponry would be the most sensible to carry on your spacecraft?

The primary types of weapons I am looking at are

  • Conventional ballistic weapons
  • EM-accelerated weapons (rail/coilguns)
  • Self-propelled weapons
  • Mines
  • EMR weapons (lasers)
  • Particle weapons
  • Drones

Conventional ballistic weapons

Probably not the most convenient in space. May still be used for handheld weapons but the velocities and distances at which space combat happen make these a bit tricky to use. Gunpowder-based weapons probably won't fire well in a vacuum anyway, as far as I see it

EM-accelerated weapons

Electromagnetically-accelerated weapons are probably fairly convenient. You fire them electrically, the payload need not that large and can be a simple ball of metal (the kinetic impact itself is fairly heft), and, for coilguns especially, there's not a lot of wear and tear. You can, as far as I understand it, achieve really impressive speeds, especially if you build a two kilometer long weapon. I imagine capital ships are, very simply put, just massive coilguns with ships attached to them and your main objective in space combat is to maneuver your ship/main gun into position safely and have it blast down stuff. Not sure if the speeds at which a coilgun fire can penetrate a warp shield well. Another idea is to have them fire plasma shells, going for burning rather than punching a hole in.

Self propelled weapons

By which I mean rockets and the like. Like conventional kinetic weaponry, probably a bit difficult to use efficiently at long distances, easy to shoot down etc. Can possibly attach small warp drives to them if warp drive miniaturization has come far enough (and production is cheap enough) that you can slap a drive to a torpedo and send it on its merry way; the spacetime distortion of a warp bubble should do significant damage to enemy hulls (and warp torpedoes may very well be able to penetrate warp shields with one of their own?). The question of whether the warp drive is pinpoint enough is also a problem.


Space is vast and it's pretty hard to observe everything, especially if it doesn't actually give off heat signatures or other such radiation. It's quite possible that mines can be potent; jettison them off in the direction of an enemy craft's flight path (or litter the area around space stations/common atmospheric entry locations with them) and mayhem ensures. It may be a good way to deter people chasing you.

Lasers/EMR weapons

Accurate, instant (unless you are fighting at a distance measurable in light seconds) and quite possibly lethal to spacecraft, though it might not pack the heaviest punch; maybe sufficient thermal armor might stop a laser from burning through a hull. Lasers are probably also really good at point defense; they can easily blast down incoming missiles, can be turret mounted to offer a wide firing arc to deal with pesky maneuverable craft and drones, and so on.

Particle weapons

Imagine a particle accelerator, only you direct the particles at your enemies. It should in theory work really well and there's a lot of kinetic energy carried.


Not a different "weapon" per se, but small unmanned drones equipped with any of the other weapons can fly in swarms to try and overwhelm enemy crafts' defenses with a quantity over quality approach, they can carry signal interference to disrupt communications, and may be more viable users of plasma weaponry to burn through hulls.

I'm mostly just assuming how things will work and there's a lot of conjecture, so I'm very interested in hearing exactly what kinds of weapons are good, and how they would be good, in a space warfare setting. How exactly do lasers impact their targets and are particle weapons better at this? Do particle weapons have to deal with cooldown like lasers? Are there significant drawbacks to coilguns (apart from being dodgeable at long distances)? And, relevant for my setting specifically, will a projectile traveling at fast enough speeds survive a strong tidal force (warp shields) better (since it'd technically be affected by it for a shorter period of time)? Are there other kinds of space-based weapons I have not considered?

  • $\begingroup$ One other kind of weaponry you left off are asteroids. As in "We attach that big engine to that 20km-in-diameter-rock and send it on collision course with enemy ship". The general idea is to sent bigger rock than shields can stop. $\endgroup$ – Darth Hunterix Aug 10 '15 at 22:28
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    $\begingroup$ You will find lots of discussion on the topic of Space Warfare in the ROCKETPUNK MANIFESTO blog rocketpunk-manifesto.com, and in the space Warfare section on Atomic Rockets: projectrho.com/public_html/rocket/index.php. Enjoy $\endgroup$ – Thucydides Aug 10 '15 at 22:34
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    $\begingroup$ This question is, imho, too broad and touches many different aspects of space weaponry. Also the title isn't very good. Maybe "What weaponry penetrates tidal field shields well?" $\endgroup$ – Tomáš Zato Mar 31 '16 at 15:36
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    $\begingroup$ Gunpowder based weapons work fine in space. They don't burn air. If they did, there wouldn't be enough in the firing chamber. For comparison, potato guns burn air, look how much bigger their combustion chamber has to be. That said, the rate of thermal gas expansion does limit their velocities too much to be useful at space-combat distances, and you really want something nuclear-powered from a power/weight ratio perspective anyway. $\endgroup$ – Perkins Oct 4 '16 at 19:00
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    $\begingroup$ @Llama_guy I did an attempt at cleaning up the question structure a little; if you don't like the changes, please feel free to roll them back - BUT consider spending some additional time on the structure of the question and the content/writing. A well structure & formulated question invites answers of higher quality. $\endgroup$ – dot_Sp0T Mar 23 '18 at 10:57

12 Answers 12


As far as I see it, much depends on the way your Alcubierre Drive works. As I cannot comment as of yet, I will attempt to answer this in two directions.

Conventional Guns

They work perfectly fine in space, the propellant already contains the oxidant as do all explosives. But you're right that their muzzle velocity doesn't compare to the more exotic mass driver concepts. However, they could be used to attack drones at very close range with saturation fire.

However, there are some concepts to increase the velocity of the projectiles, for examply by using a light gas cannon. Since we talk about the large distances, this wouldn't be feasible either.

Railguns / Coilguns

Solid projectiles can be accelerated to very high speeds while remaining absolutely accurate and not losing any power over the distance.

Solid projectiles could also have the benefit that when they are being fragmented by the alcubierre shield, they still could inflict damage with high-energy fragments. Railguns also have the benefit that you could design self-propelled weapons that can be launched via railgun, thus decreasing the time to accelerate.

Another benefit would be that vessels with a small industrial facility could make projectiles without the need to go to port, as they could melt down asteroids for material for the projectiles.

On the flight-time until hit: Over the possible distances enabled by an alcubierre drive, even light will have a delay until it hits, and launching a sufficiently large swarm of missiles will prove to be difficult to completely avoid, depending on the attack- and defensive strategies employed.

A note on coilguns: while the abrasion of the rails may be a problem, coil guns, as far as I can see, are quite inefficient in the amount of energy required, require very complex control structures to enable the magnets to work as intended, and you're required to use ferromagnetic projectiles, whereas in railguns you could use anything that conducts electricity, or use a conductive sled like a sabot and use that to propell a non-magnetic/conductive projectile.

Self-Propelled Weapons / Drones / Mines

As you wrote that combat should occur over fairly large distances, I dont see why classic combat drones make sense: they would be on their way for a very long time and represent a good target for defensive fusion bombs, MASERs and even railguns before the drones are even within their effective combat range. Secondly, the drones need to decellerate before they can reengage after passing the target once, depending on the distance that may be rather impractical.

Therefore, I would not make a difference between drones and self-propelled weapons but instead use them as one and the same. Equip them with fusion warheads and make them kamekaze. You could use them both offensively and defensively. However, they need to be shielded enough for fully autonomous control methods to work with nuclear explosions going off in a couple of hundred kilometers distance. The winning side would then be the one with a combination of more drones and better attack programs/evasion patterns.

Those drones could then also be used as mobile mines. But keep in mind that mines in general only make sense if the target needs to reach a specific location.

EM Weaponry

EM Weaponry like lasers seem to me to be only useful as a short range defensive weapon to deteriorate incoming projectiles and drones, preventing them to impact or coming close enough for their warhead to make a difference. Why is this? Well, even in space, the diameter of a laser beam will widen considerably, thus decreasing the amount of energy per cm² impacting any object at distance, as the inverse square law tells us. This may vary depending on the size and technology for generating and focusing the beam. A kinetic projectile does not have this drawback. Depending on the technology base, I would suggest MASERS or X-Ray Lasers for this purpose.

Edit: MASER is an acronym for Microwave amplification through stimulated emission of radiation, meaning a LASER in the microwave wavelength region. You can use other wavelength, though I would not go as far as using a GRASER as base, as gamma rays tend to penentrate the amplification mechanism...

Particle Cannons

I think you'd need even more resources to operate them than railguns or masers. To achieve a saturation area dense enough, they might be large and require their particle "fuel". While they may be very powerful, they will probably suffer from the inverse square law.

  • $\begingroup$ In terms of lasers, do you have any idea what wavelength would be more appropriate for point-defense, if that makes a significant difference at all? $\endgroup$ – AmiralPatate Mar 31 '16 at 14:46
  • $\begingroup$ @AmiralPatate Ah, I guess I didn't explain the term "MASER" then. Its basically a microwave laser. choose something from that range if you want to be specific. But in the end it really depends on how much energy you can dump on a target in the smallest timeframe, you could also use infrared or UV. $\endgroup$ – Doomed Mind Mar 31 '16 at 15:03
  • $\begingroup$ So what makes microwave a better choice than IR or UV? $\endgroup$ – AmiralPatate Mar 31 '16 at 15:31
  • $\begingroup$ Well, I never expected anyone to comment on this old post. A very filling answer and some good ideas I will take into consideration, thanks! $\endgroup$ – Llama_guy Mar 31 '16 at 23:58
  • $\begingroup$ @Llama_guy to be honest, I did not look at the date :) just found an interesting question not answered $\endgroup$ – Doomed Mind Apr 1 '16 at 6:51

Given the scenario as described, the primary mode of attack would be to find a way to collapse the unstable bubble of space time being used as a shield.

In inertial space, the primary weapon will still probably be a Ravening Beam of Death (RBoD) mounting a kilometre long electron beam accelerator to drive a freaking huge FEL that can pump out beams at X-ray frequencies. The RBoD can deliver enough energy to vaporize steel, ceramic and carbon fibre components in milliseconds at distances of one light second, almost the distance from the Earth to the Moon. Indeed the beam will be dangerous to a distance of a light minute, and can deliver a lethal dose of radiation at a light hour! (RBoDs are described in the Atomic Rockets website under conventional weapons http://www.projectrho.com/public_html/rocket/spacegunconvent.php, while the discussion of RBoDs vs SCoDs comes from the "Rocketpunk Manifesto" blog under space warfare http://www.rocketpunk-manifesto.com.)

As a practical matter, slow moving ships will be effectively stationary at a distance of one light second from a laser weapon of this power, and the energy being dumped into the shield bubble could be enough to destabilize it. Once it collapses, the ship is open to being sliced apart in detail, unless collapsing the shields actually causes catastrophic damage to the ship itself.

RBoD A conceptual diagram of the RBoD

The kinetic energy counterpart to the RBoD is the "Soda Can of Death" (SCoD), a device the size of a soda can accelerated in great numbers against ships carrying the RBoD. Tens of thousands of SCoD's will simply overwhelm the ability of a RBoD to track and eliminate every one, and the overwhelming mass of incoming SCoD's will strike and destroy the RBoD. The kinetic energy of incoming SCoD's could also tend to overwhelm the shield, causing a collapse and damage to the underlying ship. To cover the distance in a semi plausible timeframe, either ICBM sized missile busses need to be used, or massive rail or coilgun platforms like the SDI era conceptual project "Have Sting" (Diagram from Atomic Rockets, via Scott Lowther http://up-ship.com/blog/)

Have Sting

Railgun concept

Although you have not specified this, if there is a version of the Alcubierre drive, then you might be able to do long range attacks using drones mounting the Alcubierre drive to chase down targets at superluminal velocities, then attacking as a conventional missile or bringing a portable version of the RBoD with it (bomb pumped X ray lasers come to mind). The Alcubierre drive itself could be used offensively to manipulate the space-time around the shield, negating the effects, or amplifying effects in a runaway feedback loop and tearing the drive mechanism apart. The massive changes in space-time around the ship could also physically damage or tear the ship apart, depending on what sorts of distortions and gradients could be arranged next to the ship.

  • $\begingroup$ (Banana for scale) $\endgroup$ – Blacksilver Mar 23 '18 at 3:42

If you have Alcubierre drives, then the drive itself can be weaponised. It is expected that the forward field will accumulate photons and release them ahead of the ship when the drive field collapses, in the form of very high energy photons. By triggering a burst of Alcubierre warp in the direction of the enemy and pumping photons into the forward drive field, on dropping warp, the photons, now carrying a lot of energy, will continue on toward the enemy. See http://ut-images.s3.amazonaws.com/wp-content/uploads/2012/02/MatterOfMatter-revised-final.pdf



These special missiles are full of little lead pellets. They're actually intended for intercepting missiles, but the then-pilot "Sandy" Gray realized that there's nothing stopping you from launching them at the enemy.

A one gram projectile moving at .999c carries a ton of energy; about 500 kilotons. You can probably pack a million pellets in a missile. With a million little chances to breach the shields, one is bound to get through. As a bonus, it's basically impossible to dodge.

DISCLAIMER: I'm not a physicist and this might be wrong.

$E_K = \left( \frac{1}{ \sqrt{1 - v^2/c^2 }}-1\right) \times m \times c^2$
$E_K = \left( \frac{1}{ \sqrt{1 - 0.999c^2/c^2 }}-1\right) \times 1g \times c^2$
$E_K = 1.887×10^{15}J$

Wolfram // NUKEMAP

Godspeed, Sandy.


Provided they could get past your fancy shields, lazzorz!

Remember, in space, there is no matter to conduct heat away from you. Lasers would be a really good way to add energy to an object and heat it rapidly. If the ship is unable to deal with the excess heat, they'll have to surrender, lest they risk their crewmen being literally boiled alive.

Also, kinetic kill vehicles. Essentially, what Holdo did in the new star wars movie. Light-speed projectiles would be really hard to detect, and almost impossible to avoid, not to mention exceedingly deadly.

Also, if you're being really careful about physics, I don't think your space navy would use conventional projectiles. Every action has an equal and opposite reaction. If your ship attempts to perform a broadside barrage, your ship is going to propel itself away from its target, and will have to waste fuel correcting its trajectory, so weapons that will propel themselves without affecting the vessel (missiles that fire once detached from the vessel, lasers, etc.) Recoil-less weapons, in essence.

I'm no science-man, though. I may be wrong about what I said above.


If you plan to use the FTL drive in combat, you will need weapons with an FTL effect. Otherwise the target will outrun the weapon fire. That excludes everything on your list except for FTL missiles or drones.

If the FTL drive is used only for interstellar flights and not in combat, small ships have no advantage over little ones. Sublight speed means acceleration and delta-V, and delta-V depends on the fuel or reaction mass percentage.

  • $\begingroup$ Or worse, you could hit your own weapon, depending on how the FTL works exactly. $\endgroup$ – William Kappler Aug 11 '15 at 6:16
  • $\begingroup$ As to big ships and small ships being equal, I do not think this is always the case. In a 'drag race' scenario they will have the same performance, but if they needed to change orientation reap idly the smaller vessel may have an advantage. This is because of the greater stresses imposed on a larger structure while manoeuvring. If the ship is big enough a turning rate of only a few degrees a second could generate a severe centripetal acceleration vector in the ends of the ship. Of course that presupposes that there is a need to turn quickly... $\endgroup$ – moran Aug 27 '15 at 7:01
  • $\begingroup$ A convenient plot device to get around this could be that ships can't go to FTL in a gravity well. $\endgroup$ – Blacksilver Mar 24 '18 at 16:52

I had a similar problem when I wrote my first Sci-Fi book. I deduced that explosive projectiles that were encased in plasma were the most effective. My early weapon concept was a pump action gun, with turrets (the revolver cylinder kind of turret) mounted on the top, containing explosive charges. When fired, a field of plasma is emitted from these charges, before violently exploding after letting out the rest of the plasma at once. These prove to be very effective at penetrating through armour, and then obliterating whatever was left of it inside. Any ships floating around in space aren't going to be able to out maneuver your shots, and variations of this weapon can be created with the same basic principle of plasmatic charges to better fit your needs.


One thing you may want to take into account is litter. If you're using physical, non-guided/propelled projectiles, if you miss, then that projectile is Going Somewhere. There is in fact a whole (hilarious) rant about it in one of the Mass Effect games as to why we do not "eyeball it" since once you fire that projectile, it will keep going until it hits something, a thousand, a million years ahead if necessary. For a conscientious species, you may wish to stick to Directed Energy weapons or particle weapons.

"Sir Isaac Newton is officially the deadliest sonfoabitch in space."

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    $\begingroup$ Even particle beams will continue if it misses. That could be kind of funny, if some planet had a "weather" caused by lazer battles far away from them :D $\endgroup$ – Nuloen The Seeker Mar 24 '18 at 17:45

MatterBeam suggested Light-coupled particle beams. http://toughsf.blogspot.com/2019/02/cold-laser-coupled-particle-beams.html#more

It is essentially a particle beam with an additional guiding laser to fight the dispersion of the particles, giving you more range than you can possibly use with light-lag. The result is comparable to a Xray-FEL Any kind of particle weapon will have penetration that depends on the atoms used as well as the target, with heavy atoms generally getting stopped quicker. A proton beam may kill electronics and crew through armor if it is not thick enough, unlike a laser. Heavy atom beams can get to higher energies in the same accelerator, giving you more energy on target if you want to try melting it to slag instead.

A note on plasma shells: Any kind of plasma weapon is likely to disperse really, really quickly. Kinetic slugs, nukes, lasers, particle beams can all turn their their target into plasma, but it is generated in-situ. Transporting plasma across free space would need some form of confinement.


What about a nuclear option?

Just take a powerful enough A- or H-bomb and place a large metal rod (made from wolfram or something) close to it. Move the whole construction close to enemy, with a missile or something.

Then detonate the bomb. It provokes upward energy level changes in the electrons in the metal rod (before it evaporates away). These changes are released as gamma quants when the electrons plop downwards the energy level. You get a pretty coherent stream of gamma radiation in the direction of the longer rod axis.

This is a nuclear-powered gamma laser. Pretty cool, huh?

And speaking of long wolfram rods. If you want to attack a planet from space, just plop down such rods (or ones made from depleted uranium, for maximal fire-starting damage) from the orbit. Gravity is a bitch, inertia and kinetic energy even more so. A purely kinetic weapon, no explosives needed.

  • $\begingroup$ Explosives are practically useless in space... $\endgroup$ – skout Mar 24 '18 at 17:22
  • $\begingroup$ It's not an explosive as such, it uses a nuclear blast to power a directed gamma radiation burst. $\endgroup$ – Oleg Lobachev Mar 25 '18 at 17:14

To boil down your weapons further, you have three main types:

  • Kinetic: Conventional projectiles, Railguns, etc
  • Beam: Your lasers (light-speed) and particle cannons (near light-speed)
  • Self-Guiding: Missiles, Drones, Fighters and the like

Everyone will know where everyone else is, as there is no realistic stealth in space, thus most ship battles will occur at light-second distances, if not further. You always want to be as far away from the person trying to kill you as you can after all.

The main effect of this is the delay in information. If your sensors pick up a ship ten light-seconds away, the information your sensors give you is already ten-seconds old. Assuming you're firing light-speed weapons (beams), it'll take another ten seconds to hit, thus you need to aim at where you think the enemy will be in twenty seconds from the location you can currently see him.

For Kinetics, this problem is even worse, as your projectiles will not be moving at light speed, and will thus take more than ten seconds to reach your target.

Self-Guiding weapons however, do not have this problem. They can be launched many times further away without having to worry about predicted target location, as they will be constantly adjusting to ensure they reach the target.

No, you would thus think that Kinetics are useless compared to Beams and Self-Guiding weapons, however Self-Guiding weapons are typically much more expensive. Just compare any modern missile or UAV to a standard field gun. They may be of similar size, but that gun has much more ammo, and much cheaper. Also, Self-Guided weapons would likely move slower and be larger targets than kinetic munitions, meaning they more more easily be countered by point defence. Whether the size of an object matters for an Alcubierre shield is for you to decide.

Beams are straight-line weapons, whilst Kinetics are affected by gravity(1). This means that you wouldn't be able to hit a target on the other side of the planet you're orbiting with a Beam weapon, but you could with a Kinetic weapon. A hit from a kinetic weapon would likely be much more severe than a hit from a beam weapon. Any solid object flying at high velocity would have ridiculous amounts of momentum, and would be able to punch straight through ships. Meanwhile, a Beam weapon would be coming up against the standard radiation shielding a ship would be obliged to carry to protect its crew from solar flares and other natural, space-based radiation. Finally, Beam weapons will suffer from attenuation, meaning they do less damage at long distance. A Kinetic round will do the same damage regardless of distance, assuming it hits at all.

Thus firing solutions will generally involve volleys of self-guided projectiles, with shotgun-blast volleys of Beam weapons at long range and Kinetics at short range.

Quickly addressing Mines. Classic stationary mines would be worthless. They would easily be avoided by anyone going slow enough, and if they're going too fast, then you could just as easily use anything bigger than a fleck of paint, which chipped the windscreen of the ISS. In reality the only thing resembling mines would be drones set to hang out in an area of space, and then automatically target anything that comes into range. These would fit into the Self-Guided category above.

(1): Not actually true, but for our purposes the effect gravity has on light-speed and near-light speed projectiles is negligible.


There are lot of ideas, so I will just add some.


Droids that try to reach the other ship and pierce its hull, or disable important systems or releasing a EMP inside the ship or near the commanding centre. Creating as little debris as possible, while disabling the ships.

Plasma breathers

Shooting a cloud of plasma that can disperse after a certain distance. In close proximity it could do great damage to the ship, while it creates no debris and the shots that missed will become more harmless with distance, eventually returning to their standart gas form after it radiated enough heat. (Nebulas caused by large battles?)

Tractor beams and magnetic manipulators

You could slow down the large ships and throw around with the big ones, you could also collect surrounding debris and use it offensively.

Graviton bombs

Huge magnets released into the battle... space, that can attract ships making them crash into each other or to force a large ship to move. And the bigger the ship the greater the effect should be.

Or strong gravity generators that, when close to a long ship, force its' hull to bend and break.

Warp torpedoes

A torpedo carrying a faulty or damaged warp core, when it reaches its target it activates, doing whatever a unsuccessful warp travel does. (ripping the ship to pieces, trapping it somewhere, or just deplete its energy, so the ship would stay in one piece, or just take it out of battle for a while)


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