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Realistic combat between space warships

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Scifor Refugee

Posted: Wed Mar 07, 2007 12:59 pm Post subject: Realistic combat between space warships

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I'm curious what people think combat will be like between warships in space. In order to keep this plausible, let's assume that no unforeseen "magic" technology is developed. In other words you don't have "deflector shields" that can magically block any incoming weapon, engines that magically don't run out of fuel, "inertial dampers" that magically allow your crew to withstand 100 Gs of acceleration, etc.

Personally I suspect it would all be based around unmanned drones that are partly or completely autonomous. Drones will be able to withstand far more acceleration, and it won't be a big deal if they burn through so much fuel that they can't be recovered (unlike crewed space ships). Combat will probably involves "carrier" style ships launching drone against each other.

The weapons will probably be nuclear missiles, since it seems impractical to keep a laser or particle beam focused on another ship with the distances and speeds that will be involved.

Detection will probably mainly involve passive infrared telescopes, which would allow you to pretty easily detect any ship within a very large distance that was using an engine (and probably even any ship that wasn't). So, in general, I think everyone involved will know where everyone else is thanks to the impossibility of hiding a ship's black-body radiation in space. It probably wouldn't be possible to make a "stealthy" ship. But you could still do things like approach an enemy ship from the direction of the sun in order to blind his sensors, hide behind planets, etc.

What does everyone else think?

Guest

Posted: Wed Mar 07, 2007 1:13 pm Post subject:

During the cold war the russians had a unique solution to 'downing' US satellites by the dozen, their plan was simple, launch rockets in counter orbits and release a 100Kg,s of coarse grained sand with a gas 'trapped' between it's particles, this would rapidly spread out and any direct impact would be at around 35,000 miles per hour, enough to destroy anything.

If the guy was coming straight towards you and you closing speed was around ten miles per second - throw sand inhis face! but 'vering sidways' is not really an option, The shuttle for example cannot alter it's course my more than a few parts of a degree, it appears to but this is in fact an illusion through it's forward speed. A small 'guided' EMP bomb with tracjectory prediction software would probably be a good weapon.

Scifor Refugee

Posted: Wed Mar 07, 2007 1:53 pm Post subject:

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Hmm...sand would probably work for something like a satellite that moves in a predictable orbit, but I'm not sure how well it could work for ships maneuvering out in the solar system. Your aim will have to be VERY good to get it close enough to the enemy ship for the sand to do much damage…and even then, if the ship has armor you might just scratch up the surface. I suspect that a nuclear warhead would give you better results.

Guest

Posted: Wed Mar 07, 2007 1:59 pm Post subject:

Well it was just a throw in to show that sometimes a very cheap solution can be the most effective, at the moment, there is no maneuvering out in the solar system, we can only send craft further than the giant planets by using slingshot. As a matter of note, who would be the adversaries? - extraterrestrials?

Scifor Refugee

Posted: Wed Mar 07, 2007 2:50 pm Post subject:

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Megabrain wrote:

As a matter of note, who would be the adversaries? - extraterrestrials?

Maybe one nation on earth is fighting another...maybe the colonists an Mars are fighting the colonists on Venus...whatever.

Guest

Posted: Wed Mar 07, 2007 3:02 pm Post subject:

I think the Venusians are fully pre-occupied keeping the air-conditioners working... Laughing

Wolf

Posted: Tue May 15, 2007 4:14 pm Post subject:

Forum Lycanthrope

Joined: 15 May 2007
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It is inevitable that we're going to have battles in space one day. What they'll be like is probably going to be a near-exact correlation to the history of warfare on the ground. It's gonna be awfully crude and devastating at first, and slowly become more refined to an art.

It's very easy to blow something up in space today. Satellites, stations, and shuttles are relatively flimsy and prone to being taken out by pathetic things. In today's world, the combined velocities of a satellite and a spit-wad will make fireworks. BB guns could be the most lethal weapons brought into space.

If technology advances the state of war in space will remain the same, but the conflicts will likely become more drawn out and complex. If we assume that any "good" spaceship will have capabilities that allow it to resist the damage of space junk and meteoroids, simply dumping particulate mass into the flight path of the spaceship will become a joke.

I seriously doubt that the future space wars humanity will see will include nuclear weapons. The cost, complexity, and damage, are insanely overkill. If we ever develop a starship capable of surviving the impact of one or two conventional missiles, we'll probably have found ways of getting around or defeating nuclear weapons, too. Until starships can withstand conventional weapon punishment, using nuclear weapons in space would be like killing a terrorist by crashing the Moon into him.

Unfortunately, war in space is probably gonna be very dull. For starters, explosions are likely to be quick, and not very impressive. Second, since space is a near vacuum, there's no way for sound to travel, so we'd be shooting things without the gratifying sound of our guns, or the sounds of our rounds hitting stuff. Space warfare would be even more silent than sub warfare.

To make matters worse for the shooter, you'd probably never even see your targets in a space war. The ability to detect, identify, and target objects that aren't even in the line of sight would make space warfare akin to ICBM warfare. Choose target, insert key, click button.

There'd also be a level of ground-risk in space warfare to be concerned about. Taking out a large satellite or something the size of ISS would pose a moderate threat to folks on the ground. There's also a very good chance that your little snit in space will cause collateral damage to targets you don't want to damage or destroy. This adds complexity to space warfare because now you not only have to find and shoot your target, but you have to pick your attack such that raining debris won't take out ground objects you want to keep alive or friendly, or that the debris from the destruction of your target doesn't cause a trans-orbital disaster that sends space junk into you, your friends, other satellites, and so on...

Jellyologist

Posted: Tue May 15, 2007 9:22 pm Post subject:

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Joined: 12 Jan 2007
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Scifor Refugee wrote:

What type of shielding known to physics would protect the skin of a spacecraft against hitting sand at high speeds? The amount of energy released in a collision of sand and a moving spacecraft would destroy the ship in a second. Also, ships don't have much maneuverability. They would require phenomenal amounts of energy to make any evasive action. Any type of added armour would add so much mass that they'd be sitting buckets. Unlike in fantasy shows, spacecraft are subject to the laws of mass and and energy.

Wolf

Posted: Tue May 15, 2007 9:47 pm Post subject:

Forum Lycanthrope

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Jellyologist wrote:

Don't take this the wrong way, but I think you need to think outside the box a bit.

Today your assumption is very true. We don't have anything (at least not in space) that can protect a spacecraft from communist sand....but that's not to say we won't at some point in the future. Aside from the possibility of deflection fields and the like, what about countermeasures? The sand isn't guaranteed to only hit the spacecraft, is it?

On the maneuverability side, the attack would have to be launched fairly close, otherwise an orbiting object (such as a satellite or ship) could have time to escape, especially if it utilized something like an emergency countermeasures rocket or whatnot.

If you assume that the attacker gets their sand rocket on target, they have three options. Either release sand far away, release close by, or release point-blank.

If they release far away, even at 70k miles an hour there's enough time for an object to move out of the way of a static-trajectory cloud of sand.

If they release point-blank, why use sand at all? If you can get that close, why not just attack the object directly? Or with a small charge, using the fragments of the missile itself as fodder?

And what about countermeasures against the missile itself, even before it releases its marbles? On detection of a launched missile, the defending object could either begin evasive maneuvers, launch countermeasures, or even attack the missile itself. Or even all three.

Perhaps this answers the "laser weapons" argument mentioned in posts above? Enemy launches its dust missile, defender takes it out with a laser round.

Since even at 70k miles an hour the sand particles are hardly examples of relativistic cannon shot, impact with another decent object would be enough to prevent further damage. If these were relativistic rounds, they'd cut through anything like a hot knife through butter, but these antisocial grains of dirt aren't traveling anywhere near 600-million miles an hour. If they were going any faster than orbital velocity, they'd make a bee-line out into space.

Jellyologist

Posted: Wed May 16, 2007 7:11 am Post subject:

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Joined: 12 Jan 2007
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You are still not aware of the basics of physics. Distance is not the issue. The issue is one of acceleration and decellaration. And one can invoke a word like 'deflection field' but it has no more meaning than 'magic wand' if not given some basis of how the physics would work.

As you said, one can think outside the box but that box still needs to involve the properties of mass and energy and not the gobblygook of Star Trek.

Wolf

Posted: Wed May 16, 2007 7:56 am Post subject:

Forum Lycanthrope

Joined: 15 May 2007
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Jellyologist wrote:

You are still not aware of the basics of physics. Distance is not the issue. The issue is one of acceleration and decellaration.

Since any object you release, sand or not, will have a predefined trajectory, then there is a calculated point at which interception will occur. All a satellite need do is move outside of that interception point, and the attack fails. Distance certainly is an issue because unless the attack is point-blank, there is a time difference between the release of the sand, and the impacts. If a satellite is equipped with a propulsion means that can move it beyond the interception point in the time allowed, then the attack will fail.

A lot of movement in space is done slowly because movement is costly. Rather than achieve a new position quickly at the cost of large amounts of fuel for going and stopping, changes can be done gradually with minimal fuel, over time. That concept works well for satellites, shuttles, and space stations who aren't in a hurry, but I think the theater of war will require different strategies.

Besides, a spacecraft doesn't have to make a sharp, right-angle turn to change course. It need only move beyond the swath of the incoming sand cloud.

I predict that if we ever actually have such weapons, you wouldn't want that sand cloud to be very big. Given the velocities involved, and the density of satellites in orbit, making a big cloud would not only be wasteful, but would carry a high potential for disaster. This improves the odds for the defending craft, though.

Jellyologist wrote:

And one can invoke a word like 'deflection field' but it has no more meaning than 'magic wand' if not given some basis of how the physics would work.

As you said, one can think outside the box but that box still needs to involve the properties of mass and energy and not the gobblygook of Star Trek.

So are you saying that we will never develop technology that will allow us to deflect a particle of sand traveling at high speed?

If so, not only is that a dead end, but spaceflight is ultimately doomed. There's tons of stuff floating around out there. If we don't figure out how to interact with it, we're gonna start running into it (and already do). Space junk is already becoming a problem.

Deflecting material is a lot easier than blocking it, which is why I say "deflection." Armor is heavy, and we already know that we can effect particles using magnetic, static, and plasma fields, which is why I say "field."

You got any ideas? Or do we just give up on the theoretical session, comrade? Wink

Lucifer

Posted: Sun May 27, 2007 2:13 pm Post subject:

Forum Junior

Joined: 14 Jan 2006
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If your enemy throws sand your way... you'll throw dust against his sand. Don't make things complicated, dudes... Laughing

(FAI... a ferromagnetic dust could be moved at very high speeds along the force lines of a oscillating magnetic field ahead of the ship, hitting incoming "sand" from the sides. Even today we could project such a "dust shield" several kilometers thick...)

Each potential weapon haves its own shortcomings. Anything authonomous using EM guidance of any wavelength can be either scrambled, jammed or misled by decoys.

EM radiation can only be focused over limited distances; even the most coherent laser will spread and fade over thousands of kilometers.

Anything kinetic can be either avoided or plain intercepted with a spread shot ("sand"). This includes non-guided warheads.

Explosions are almost useless; only shaped charges would be of some use, supposing that breaching the hull was a meaningful damage to the attacked vessel. As void goes, probably having multiple layers of a refractive armor with vents would quickly drain pressure from a explosion by "bouncing" it on a lower layer and venting the gasses through the upper, damaged one.

Also space offers exotic alternatives, like enveloping a ship in a oxidating mixture. A cloud of oxygen and hydrogen could generate temperatures of about 4000 degrees; more active oxydizers, like a mix of fluoride and carbon, could generate a cloud of plasma that would stick electrostatically to the hull. Such oxydative attacks would annihilate every sensor on the attacked vessel.

In all cases, stealthiness would be standard pocedure; ships would have means to store their heat in a high-temperature "coils" which could be jettisoned without unveiling the ship's position and bearing, allowing the ship to be kept as "cold" as possible. Optical sensors probably would rely on ocultation of distant objects as any hidden ships moved between the beholder and them. There would be an arms race between locating any uncharted small objects, and concealed ships disguised as harmless rocks... and probably artificial mock-ups to fool the enemy sensors and charts.

As for the degree of automation, it would be a slippery slope... any authonomous weapon can be potentially turned against you by a superior "hack", and so probably you don't want them to be the most deadly in the block... probably some sort of remote guidance would be the rule, yet then space is BIG and travel time of any signal could be ludicrously and impractically long... so you should expose your "pilots" and with them their inferior (less maneuverable, more delicated) crewed ships, to a full-auto attack... Full-auto would likely be one-shot weapons ussed for assault to prevent the danger of hacking, more similar to cruise missiles than to real ships. Cool

All in all, it all would depend upon why you where fighting, over what, where and when...

Airplanes began their military career as spotters; wiht spotters were born hunters of the spoters... then as heavier payloads were available, they became some sort of "artillery" which should be shot down with pursuit planes... the evolution of combat plane has been depending always on ground missions; evne now, thye survive due tot heir abbility to be sued many times and react to threats in a way an automated weapon can't. On the other hand, navies historically where intended as disrupters of enemy trade. So, what role would play a space fleet? It would all depend upon economy...
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Scifor Refugee

Posted: Wed Jun 06, 2007 11:06 am Post subject:

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Joined: 02 May 2005
Posts: 953

Woops, I lost track of this thread. I'll respond to several people at once.

Wolf wrote:

I seriously doubt that the future space wars humanity will see will include nuclear weapons. The cost, complexity, and damage, are insanely overkill. If we ever develop a starship capable of surviving the impact of one or two conventional missiles, we'll probably have found ways of getting around or defeating nuclear weapons, too. Until starships can withstand conventional weapon punishment, using nuclear weapons in space would be like killing a terrorist by crashing the Moon into him.

The advantage of nuclear weapons is that you don't have to get your missile very close to destroy the enemy ship. Yeah, a conventional explosive (or even a missile with no warhead that relied on kinetic energy to do the job) would be more than enough if you can actually bring your missile into contact with the surface of the enemy ship.

Quote:

Jellyologist
What type of shielding known to physics would protect the skin of a spacecraft against hitting sand at high speeds? The amount of energy released in a collision of sand and a moving spacecraft would destroy the ship in a second. Also, ships don't have much maneuverability. They would require phenomenal amounts of energy to make any evasive action.

There are several reasons why sand seems like a stupid idea. First, it is only useful if there is an extremely high velocity difference between the sand cloud and the target ship. Obviously that won't always be the case - for example if one ship is chasing another ship, their relative velocities might be very close.

Second, it does not seem feasible for any reasonably-sized clouds of sand. Exactly how much sand were you planning on throwing? Suppose you disperse a metric ton of sand into a cloud that's 200 meters in diameter by the time it hits the enemy ship. The cloud would have 0.24 grams of sand/m^3. If the relative velocity was 10 km/s, that would give our 0.24 grams of sand about 12 kj of kinetic energy - which is about the energy of 2.8 grams of TNT. If we assume that the cloud is timed perfectly so that the ship passes through all 200 meters of it, the ship ends up absorbing an energy equivalent 560 grams of TNT/m^2 of hull. Even simple plate steel would be more than sufficient to cope with that. Note that this seems like a best-case scenario in which there's a very high closing velocity between the sand and the ship, as well as a large amount of sand grouped into a pretty small cloud. Yeah, you can put in huge numbers for the mass of the sand, or very small numbers for the size of the could, but things start to get ridiculous pretty quickly. For comparison, a 1 megaton warhead detonated at 200 meters would deliver the equivalent of 240 kg of TNT/m^2.

Quote:

Any type of added armour would add so much mass that they'd be sitting buckets. Unlike in fantasy shows, spacecraft are subject to the laws of mass and and energy.

If the ship has powerful engines, the only real limit to its acceleration would be how many g-forces the crew could withstand. An efficient fusion or fission engine could easily move an armored ship around at several Gs worth of acceleration.

Quote:

Lucifer
In all cases, stealthiness would be standard pocedure; ships would have means to store their heat in a high-temperature "coils" which could be jettisoned without unveiling the ship's position and bearing, allowing the ship to be kept as "cold" as possible.

I hope you aren't suggesting that the ship make itself stealthy by transfering its heat into "coils" that are already hotter than the ship Wink

Lucifer

Posted: Fri Jun 08, 2007 9:12 am Post subject:

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Scifor Refugee wrote:

Quote:

(...)Lucifer
In all cases, stealthiness would be standard pocedure; ships would have means to store their heat in a high-temperature "coils" which could be jettisoned without unveiling the ship's position and bearing, allowing the ship to be kept as "cold" as possible.

I hope you aren't suggesting that the ship make itself stealthy by transfering its heat into "coils" that are already hotter than the ship Wink

I was thinking more on how to cool down high temperature sources by other means than just radiate heat to space 24/7.

Something like "let's have the reactor heat up a "coil" and jettison the coil instead of have a cooling system which implies a 20 m2 radiator at 500 K 24/7".
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Wolf

Posted: Wed Jun 13, 2007 3:44 pm Post subject:

Forum Lycanthrope

Joined: 15 May 2007
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Scifor Refugee wrote:

Not to be short, but we've had the ability to make things explode before they hit something, for about 100-years. The explosive missile wouldn't have to actually hit anything, and you can get a plenty big enough explosion from a conventional missile. Nuclear weapons would be overkill, and the risk of causing damage to other nearby and cross-orbiting non-targets would be even greater than with a smaller explosion.

Scifor Refugee wrote:

That's why the idea was to release the sand from the opposite direction of the target. You're right, a chasing missile releasing sand would be ineffective, and I doubt anyone would waste the time and money to create a "sand accelerator" missile. Such a weapon would likely be strictly designed for releasing the sand in the opposite direction.

Scifor Refugee wrote:

Second, it does not seem feasible for any reasonably-sized clouds of sand. Exactly how much sand were you planning on throwing? Suppose you disperse a metric ton of sand into a cloud that's 200 meters in diameter by the time it hits the enemy ship. The cloud would have 0.24 grams of sand/m^3. If the relative velocity was 10 km/s, that would give our 0.24 grams of sand about 12 kj of kinetic energy - which is about the energy of 2.8 grams of TNT. If we assume that the cloud is timed perfectly so that the ship passes through all 200 meters of it, the ship ends up absorbing an energy equivalent 560 grams of TNT/m^2 of hull. Even simple plate steel would be more than sufficient to cope with that. Note that this seems like a best-case scenario in which there's a very high closing velocity between the sand and the ship, as well as a large amount of sand grouped into a pretty small cloud. Yeah, you can put in huge numbers for the mass of the sand, or very small numbers for the size of the could, but things start to get ridiculous pretty quickly. For comparison, a 1 megaton warhead detonated at 200 meters would deliver the equivalent of 240 kg of TNT/m^2.

Space debris traveling in orbit at approx. 70,000-mph puts a lot of holes in things in space. Dust pits the space-shuttle deeply, and something the size of a BB would probably go straight through the hull. Although the hit from grains of sand traveling at those speeds may not be too significant, it can collectively cause problems, especially if the target is not entirely (or at all) armored. If you use something like marbles, instead of sand grains, the event gets more exciting.

Scifor Refugee wrote:

Quote:

Any type of added armour would add so much mass that they'd be sitting buckets. Unlike in fantasy shows, spacecraft are subject to the laws of mass and and energy.

Two things:
1. The armor doesn't necissarily have to be all-encompassing. It could simply be a shield large enough to cover the profile of the ship from one angle. When an incoming threat is detected, the ship could simply rotate, aiming the shiled at the threat.

2. I highly doubt that any typical booster rocket converted to emergency counter-measure use, would not be able to shift a spacecraft rapidly. The extra mass of the armor shield would have to be several times the weight of the spacecraft to make a significant effect on a large booster engine, and such a weight would probably be far from the weight of the needed armor.

Scifor Refugee wrote:

Lucifer wrote:

In all cases, stealthiness would be standard pocedure; ships would have means to store their heat in a high-temperature "coils" which could be jettisoned without unveiling the ship's position and bearing, allowing the ship to be kept as "cold" as possible.

I hope you aren't suggesting that the ship make itself stealthy by transfering its heat into "coils" that are already hotter than the ship Wink

I think Lucifer is talking about a counter-measure for heat-seeking technology. We do the same sort of thing today when airplanes jetison flares to draw off heat-seeking missiles. If the anti-spacecraft missile used heat to track its target, such countermeasures might be feasible...but I personally think it's unlikely that such missiles would exist. There's better ways to locate targets in space than heat.
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Wolf
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