Sci-Fi Idea

[Darth Wong]

The point with the comic was nothing with the missiles: it was to point out that problems that seem easily solvable in space can turn to be very much complicated then initially thought, due to the uniqueness of zero-gravity (this works the other way around as well).

Oh for fuck's sake, that situation is not REMOTELY analogous. The reason it's so complicated is that we have almost no infrastructure up there. Everything must be done from down here. How is that even vaguely relevant to this discussion?

In this case, the spaceship/spaceplane (don't know what to call the Flying Chicken) has to change its tight schedule due to a minor mechanical error that would be otherwise quickly fixed in an another environment. Have you heard of a boat that had to stop because it couldn't throw something overboard?

What I'm trying to say, is that something that looks fairly trivial from theory can be a big technical challenge in reality, and this is especially true when it comes to astronautical engineering, as it is such a different environment.

What the fuck makes you think I don't know this, moron? How it is related to any point I made? Are you just trying to bolster your credibility by pointing out shit that any stupid asshole with Google should know?

If the enemy has powerful lasers for point-defense, it costs him a lot less to shoot down your missiles than it cost you to fire them.

True. On the other hand, if one missile slips trough the defences then it will cost the enemy several times more, while a laser blast can be survived with much less armour then what would be required to survive a nuclear blast (which I doubt one can).

And you make this conclusion without even explaining how far away this blast is, based on ... what, exactly? Instinct? Subjective impression? Tea-leaf reading? Your horoscope?

If you can lug around that much shielding, then sure the idea is worthless. Then you just have to make your regular contact-hit and blast the spaceship to pieces your regular way. However, the trade-off is that with this tactic, there is less chance of the enemy being missed or that the enemy can "dodge" by maneuvering with full burn (as likely that will work).

Just how close do you expect this nuke to be going off? You act as if some truly massive amount of shielding is required.

Another thing. I said x-rays. Now that I think about it, shouldn't it be gamma rays? Or do both happen?

Who cares? The point is that a metre of water can stop pretty much all of it, so you really don't need stupendous armour.

[Axiomatic]

If the missile course-corrects, which is the whole point of it beign a missile in the first place, it announces where it is. Which is when you blow it up.

And if the range is such that you have even a remote chance of dodging a laser, then missiles will be completely useless since they'll take hours to get to their targets, unless you're shooting missiles at significant fractions of c, in which case you're supremely awesome and deserve to win anyway.

I'm suggesting here that lasers will always destroy all missiles before they reach you because the lasers aren't in a hurry. The missiles take so long to get anywhere that the targetting computer can shoot one, play a couple of rounds of Tic-Tac-Toe to remind itself that the only way to win is not to play, then shoot another, and repeat.

Missiles could do massive damage if they had hyperdrives, though.

[Junghalli]

I'm suggesting here that lasers will always destroy all missiles before they reach you because the lasers aren't in a hurry. The missiles take so long to get anywhere that the targetting computer can shoot one, play a couple of rounds of Tic-Tac-Toe to remind itself that the only way to win is not to play, then shoot another, and repeat.

The diffusion rates and cool-down times of your laser are the serious issue. These are probably going to be the limiting factors on how effective your point defense lasers are, not your ability to target the missiles.

Say your laser has the 5 mile effective range of the theoretical 100 KW laser described here, for instance, and the missiles are travelling at 10 km/s, you have less than 10 seconds to shoot them. Say there are three times as many missiles as you have lasers, and the cool-down time for your lasers is five seconds...

[Junghalli]

Ghetto Edit: actually for my example above to be valid the laser would have to have 10 times the effective range of the theoretical 100 KW laser described in the article. If the range is 5 miles and the missiles are moving at 10 km/s you have less than one second.

Boy did I fuck that one up...

[Gullible Jones]

Also, it's probably wrong to assume that lasers would be as effective as missiles. Lasers are not as efficient as missiles; when you scale them up, waste heat becomes a problem.

[Junghalli]

Also, it's probably wrong to assume that lasers would be as effective as missiles. Lasers are not as efficient as missiles; when you scale them up, waste heat becomes a problem.

Indeed, when you consider that the 100 KW laser I used in my example would use 1 MW of electrical power, and IIRC would be designed to destroy incoming missiles by setting off their fuel and explosives rather than actually destroying them through brute force...

Here's an interesting thought: what if you can make lasers so good that missiles are basically a non-threat, but can't make practical antiship lasers? Maybe they'd starting building armored missiles?

[Junghalli]

Re: stealth in space. Darth Wong is right that you may be able to negate the minute-to-minute waste heat problem by the means he suggested. The real problem is that to get anywhere you have to fire your engines at some point, and that will be obvious over the whole solar system. You can drift toward your target under "silent running", but you'll at some point have had to fire your engines to put yourself on an intercept course, and when you do that the other guy is going to know exactly where you are and when you're coming.

Maybe you could use cold-gas thrusters or some similarly low-energy propulsion, but it'd be really slow. Even an acceleration of .01 m/s^2 is going to be detectable 1 AU away, with current off the shelf technology (as opposed to the more advanced purpose-built shipping-monitoring systems a militarized spacefaring civilization is likely to have). And probably totally unviable if your ship has to get out of a gravity well first.

You also have to take into account the fact that while it will be impossible to track every object in the solar system as you get closer to a major facility of a militarized spacefaring civilization you can expect the space to be more and more heavily monitored. It's going to be rather difficult to sneak up on something in, say, LEO.

[Gullible Jones]

Also, it's probably wrong to assume that lasers would be as effective as missiles. Lasers are not as efficient as missiles; when you scale them up, waste heat becomes a problem.

Indeed, when you consider that the 100 KW laser I used in my example would use 1 MW of electrical power, and IIRC would be designed to destroy incoming missiles by setting off their fuel and explosives rather than actually destroying them through brute force...

Here's an interesting thought: what if you can make lasers so good that missiles are basically a non-threat, but can't make practical antiship lasers? Maybe they'd starting building armored missiles?

Smart bullets, with cold gas thrusters for maneuvering?

[Ford Prefect]

Here's an interesting thought: what if you can make lasers so good that missiles are basically a non-threat, but can't make practical antiship lasers? Maybe they'd starting building armored missiles?

Your default options are 'make your missiles last longer' or 'fire more missiles at once'. I think we all know the excellence of clouds of guided explosives tumbling through space, and thus it should be the only default option (well, not seriously, but saturation is fairly reasonable).

[Machine Ghost]

As for space stealth: it is possible (but only through quantum levels of technology).

Basically you wrap your ship in something that either does not conduct heat or conducts very little. Just inside of this wrapping, you blanket the ship with pipes carrying gas which will absorb the heat generated by the ship. Then the gas is pumped through the ship to a miniature wormhole, where it is sent somewhere very far away. If you can remove the whole gas part by channeling the heat straight into the wormhole that makes things better.

This only addresses internal heat, exhaust plume on the other hand might be harder to cope with. Maybe if you have another wormhole mounted on the back of the ship so the exhaust goes into that.

As for missiles:
You can make more missiles, or you can make better missiles.

If you make more missiles they will start to get more bunched up resulting in more kills from anti-missile nukes or debris. Also the more missiles getting zapped, the more debris they are giving off for their friends to run into.

If you make better missiles you start with evasion, then armor, then their own decoys and countermeasures, submunitions and plenty of other things.

By this point they are small space ships in their own right, so here is my solution to the missile problem.

To start off with, and to avoid confusion, I will call them drones for now. Each drone will be armor, ablility to dodge, and smart enough not be be second-guessed by defensive gunners, also they will have their own missiles, much stupider though. These drones will approach the target, showering it with ECMs, decoys, and low powered lasers to blind the sensors. Once near enough, they will fire off their own weapons, probably dumb-fire rockets or slightly-smart missiles. These missiles would normally not be smart enough to survive being fired from ship-to-ship distances, but when fired from much shorter distances they have a chance of both surviving and doing damage. After its payload is loosed, the drones can either crash into the target or stop and wait for recover and rearmament.

[RedImperator]

If you make more missiles they will start to get more bunched up resulting in more kills from anti-missile nukes or debris. Also the more missiles getting zapped, the more debris they are giving off for their friends to run into.

Why would this be the case? Even on a planet, it would be trivial to achieve enough separation between the missiles that the chance of taking down more than one with one shot is close to zero. There's no reason the missiles would be traveling in tight clusters.

The problem with missile swarms is that you multiply the mass the firing ship has to carry around between battles. You have to either reduce the total number of volleys your ship can fire, decrease mass somewhere else (and hence sacrifice some other capability), or carry more propellant (which translates to "the ship costs more", plus a host of other problems).

[Ford Prefect]

The problem with missile swarms is that you multiply the mass the firing ship has to carry around between battles. You have to either reduce the total number of volleys your ship can fire, decrease mass somewhere else (and hence sacrifice some other capability), or carry more propellant (which translates to "the ship costs more", plus a host of other problems).

Truth be told, missile swarms only really work if you can reasonably produce a missile which is a fraction of the size of a regular one, yet generally matches the normal missile's performance. Which may border on the technologically impossible depending on the universe in question.

[Darth Wong]

As for space stealth: it is possible (but only through quantum levels of technology).

By "quantum", you apparently mean "magic".

Basically you wrap your ship in something that either does not conduct heat or conducts very little. Just inside of this wrapping, you blanket the ship with pipes carrying gas which will absorb the heat generated by the ship. Then the gas is pumped through the ship to a miniature wormhole, where it is sent somewhere very far away. If you can remove the whole gas part by channeling the heat straight into the wormhole that makes things better.

Yup, that's what I thought. Perhaps instead of this technology, you could have a Level 12 Wizard who sacrifices a live rabbit and then casts a "vanish waste heat" spell. I think you have to roll some dice to see how well it will work.

[Ford Prefect]

As for space stealth: it is possible (but only through quantum levels of technology).

By "quantum", you apparently mean "magic".

Going this far, he might as well invoke Alastair Reynold's almost certainly sueprnatural cryo-arithmetic technology, where heat is computed away. Asmittedly, I love his books, but it borders on Xeelee Sequence nuttery when it comes to some pieces of technology.

At the very least you're not carrying around a goddamn wormhole on your rear end, and hoping that people wont notice the massive rip in spacetime.

[Darth Raptor]

Space warfare won't be boats in space, planes in space or submarines in space. It will be spaceships in space. People who cling to their naval stealth fixations should just go write submarine stories. It's obviously what they want anyway.

[Junghalli]

Truth be told, missile swarms only really work if you can reasonably produce a missile which is a fraction of the size of a regular one, yet generally matches the normal missile's performance. Which may border on the technologically impossible depending on the universe in question.

I think two-stage missiles like modern ICBMs might be the way to go. You have a first stage that it uses for most of its propulsion, then before it gets in CIWS range that breaks apart and releases five or ten smaller missiles. With chemical rockets a smaller missile should probably have a higher acceleration, although depending on the range of the PD lasers they may only get a chance to use a second or two's worth of fuel anyway.

It may also help to wrap the second stages in a layer of material with a high reflectivity and an underlayer with a high specific heat and melting point. It's not really much in the way of armor, but anything that forces the enemy laser to put more energy into destroying each missile will reduce its refire rate.

Of course, you can use antimissiles to intercept the missile first stages, but there's going to be a limit on how many of those you can carry, because it eats into the mass burden available for your missiles.

[Ford Prefect]

I think two-stage missiles like modern ICBMs might be the way to go. You have a first stage that it uses for most of its propulsion, then before it gets in CIWS range that breaks apart and releases five or ten smaller missiles. With chemical rockets a smaller missile should probably have a higher acceleration, although depending on the range of the PD lasers they may only get a chance to use a second or two's worth of fuel anyway.

It may also help to wrap the second stages in a layer of material with a high reflectivity and an underlayer with a high specific heat and melting point. It's not really much in the way of armor, but anything that forces the enemy laser to put more energy into destroying each missile will reduce its refire rate.

Of course, you can use antimissiles to intercept the missile first stages, but there's going to be a limit on how many of those you can carry, because it eats into the mass burden available for your missiles.

I was thinking about submunitions, actually, but I was worried that having the mini-missiles clustered together might allow for PD laser systems to detonate the whole shebang early on in the piece. On the other hand, there is something to be said about having a larger engine provide initial velocity, so the second stage missile cloud can devote more fuel to changing vector, as opposed to wondering about getting up to speed.

[Junghalli]

I was thinking about submunitions, actually, but I was worried that having the mini-missiles clustered together might allow for PD laser systems to detonate the whole shebang early on in the piece.

With a two-stage missile this shouldn't be a problem unless the enemy is using nuclear or fragmentation antimissiles or some sort of (hideously inefficient and energy-consuming) wide-beam laser, and easily countered by having the second stages leave the first stage before they come into PD range and use light thruster burns to spread themselves out a bit.

[Machine Ghost]

As for space stealth: it is possible (but only through quantum levels of technology).

By "quantum", you apparently mean "magic".

Not exactly. If you allow for FTL, then "portable" wormholes should be too implausible. And the hole does not have to be that big, just large enough to pump a stream of something with a high specific heat through.

But if we are only going to use stuff that we know exists, then it is true that stealth is impossible.

[Darth Ruinus]

Not exactly. If you allow for FTL, then "portable" wormholes should be too implausible. And the hole does not have to be that big, just large enough to pump a stream of something with a high specific heat through.

And, as Ford Prefect points out, the problem is then hiding the wormhole.

You "solved" the problem by making a more complex and ridiculous problem.

[Machine Ghost]

And, as Ford Prefect points out, the problem is then hiding the wormhole.

You "solved" the problem by making a more complex and ridiculous problem.

Some how I think that if you can produce and contain a hole in the time-space continuum, hiding it should be within your grasp.

[Beowulf]

Cryo-arithmetic engines appear to be loosely based on something that isn't physically impossible, called reversible computers, which take much less power to run than a normal computer (potentially dissipating zero power). The problem is that it's a fairly new field, and thus has little maturity.

[Machine Ghost]

I don't know anything about working with wormholes, but just because you can make and contain something doesn't mean hiding it is easy.

I don't know anything about wormhole. And people don't even know if they exist/or are possible.

As for the farm animal metaphor. You could put them in a building with a very good A/C system and no one would know. That is within your reach.

If I have to guess, I would say wormhole-stealth would be used rarely, and not even be considered by civilians, so the power usage, and cost would probably be astronomical.

[Junghalli]

How obvious would a wormhole be anyway? What sort of radiation etc. would it emit?

[Machine Ghost]

How obvious would a wormhole be anyway? What sort of radiation etc. would it emit?

That we don't know.

From what I understand, physicists seem to believe they are plausible, but astronomers havenn't found any yet. So if they do exist they are pretty sneaky already, or look like something else.

But then man-made wormholes might be a different story. Who knows.