Meditations on Space Combat

[Elok]

Sorry I haven't been on lately, but my GF visited for Xmas and I like her more than you guys. Them's the breaks. But she's gone off on a shopping trip with my mother and sis-in-law for some female bonding experience I cannot comprehend, so I'm taking the opportunity to talk with you.

I got Insultingly Stupid Movie Physics for Christmas (the book, recently published by the same guy who does the Intuitor web site). It's got some fun stuff, including an all-too-brief reflection on what realistic space combat would look like. Here are my ideas:

*Detection and stealth functions would be absolutely the most important features. There's a lot of space to hide in, a lot of flotsam of varying sizes that could be enemy ships and plenty of radiation to screw up sensors. If enemy ship spots you before you spot him, you're dead, because

*There's absolutely no reason I can think of not to use nukes in space. I'm not sure how effective they would be without an atmosphere to cause shockwaves in, but there's always mass drivers (a man-sized shell traveling at half the speed of light would have a LOT of energy, no explosives needed and no worries about air resistance).

*Spaceships, like submarines, are distinctly alien environments for human beings. Cramped quarters, no gravity or a very strange artificial variety, and total reliance on life support systems. A single hit that knocks out the life support will kill all the crew in moments, or at least doom them to death. The ship might be able to fight on without them, but with the crew dead...

*You can't really dodge either, because a ship traveling at any speed will have too much inertia to overcome without killing the crew with evasive maneuvers. A missile will inevitably be able to outmaneuver its target as well. Assuming you see the shot coming at all. The need to protect the human crew is all-around crippling, so I imagine unmanned attack drones would be very useful.

*Of course everything in ISMP applies: fight from a distance, since shrapnel is lethal, etc. And this is all barring the invention of shields, inertial dampers, and all that other sci-fi crap which is by current understanding not possible.

Thoughts from physics/military wonks?

[Saras]

best.thread.ever.

[onodera]

I remember having a lengthy discussion about interstellar warfare. I was pro-missiles, my vis-a-vis - pro-drones and pro-mass drivers.
I think evasive manoeuvres will work very well against mass drivers, especially if you minimize the stress by making the hull spherical so you can evade.

[Sandman]

*Spaceships, like submarines, are distinctly alien environments for human beings. Cramped quarters, no gravity or a very strange artificial variety, and total reliance on life support systems. A single hit that knocks out the life support will kill all the crew in moments, or at least doom them to death. The ship might be able to fight on without them, but with the crew dead...

Surely the crew could wear spacesuits. Also, the phrase 'doom them to death' is awesome.

[onodera]

Okay, let's begin in the beginning.
Who are the combatants? I doubt we will ever meet aliens, so it must be another armed conflict between human factions.
Also, there's no FTL or teleportation or consciousness uploading, of course, so let's split the space into two separates theatres of war: Solar system and local interstellar space. I do not take low orbit into account, because that's as foolish as a nuclear war -- one explosion, and the debris leaves everyone earthbound.
Also, without habitable bases (either orbital docks or Moon colonies) any expansion will be stifled by the exorbitant cost of space launches: right now it takes a lot of fuel and money to launch a satellite, but to send a whole ship, a resource gatherer that can make profit and not just house several scientists, from Earth into space...
Also, I doubt any private companies will be able to cough up enough dough to keep up with the state space programs (they still can build only really high-altitude jets, not something that can orbit the Earth), so the space resource gathering (heavy isotopes of hydrogen might be one thing we'll be after) will be done either by the states, or by state-supported corporations (think NASA meets Dutch East Indian Company). The second option will also let the state wage proxy wars, so I think it'll be more likely.
At first, the conflicts will be really trvial: destabilizing your competitior's engines by flying too close, dropping some debris to make them change their course, etc. The first attack that will claim human lives will change it all. Citing safety measures, the spaceships will have their first defence systems added: probably something like a very thick layer of dense foamlike substance to cushion the impact of small particles. And probably even their first weapon systems: missiles to "destroy unavoidable small asteroids". Impactors will probably be too heavy and imprecise to be used: don't forget the distances of thousands of kilometers.
TBC

[Blaupanzer]

The energy generated by the ship's source can be used in a number of ways with military relevance. First, the life support systems will not overlap and will include sealants the hull will both generate and heat. Second, the ship will use rail guns to deflect small objects and tear holes in missiles and opposing ships. (As with all projectile weapons, one can also tear holes in the goodguys.) Next will be projected electroenergy beams aimed at disabling the electronics of the missiles or ships. Last would be nukes, their problem the indiscriminate nature of their damage. (A nuclear Claymore mine comes to mind where most of the damage is directed in a specific direction with only a small backblast.)

With the exception of the nuke Claymore, all of these technologies exist now. Two have had considerables due to the atmosphere and gravity. Both the electronic beam and the rail gun have considerable promise in the vacuum and zero gravity of space.

Speed will be a considerable problem in space in terms of patrol-type speeds and for one in describing to a second the speed of a third. While the geometry exists for that, humans don't normally speak geometry. What you have is a human translation of the method by which ship one's speed relative to ship two is expressed in a form that permits ship one to desribe the speed and trajectory of ship three to ship two. This becomes immensely more complex as more ships are added. Thus will decisions be made on what to launch, where to fly (avoidance or intercept), and how to distribute the ship's available energy toward future options.

One honest question: In zero gravity, why is it that "You can't really dodge either, because a ship traveling at any speed will have too much inertia to overcome without killing the crew with evasive maneuvers." Haven't kept up with why turning presumably adds gravity to the point of crushing the crew even if we put them in gravity resistant battle-station chairs. Note that no available technologies we know and have tested get us past about 20% of the speed of light and even that is theoretical.

[Lancer]

Evasive maneuvers are pretty hairy. Checkov wen't flying over the railing once.

Mass drivers sound pretty cool. However if you miss then well you've got a chunk of some crap moving rilly rilly fast and anything in its path is going to have a bad day. Except maybe a star. It would punch through the Earth's atmosphere alot easier than the double titanium reactive armored laser shielded hull of an Acme Imperial Cruiser that's for sure. When it hit the ground at just short of warp 9 in an overheated plasma state, well goodbye Sunday BBQ, hello extinction event.

The natural enemy of humanity would be the skull sucking locust aliens bent on a brain drain the world has not seen the like.

[DanS]

I'm skeptical about mass drivers. Spaceships will be constructed to handle orbital space debris gracefully. Space debris is moving at a much faster clip than a mass driver would generate.

I would choose lasers or masers as my weapon of choice. You might even ram an enemy ship, grapple and board it.

[Zkribbler]

Battles in deep space will be almost impossible. Planets are very far apart. Therefore, high speeds will be necessary for travelling between them. Ships will be able to carry very little, if any, extra fuel because of the weight problems. Thus, ships will have essentially NO ability to maneuver, either to defend or to attack.

Mass drivers might sound cool, but they're over engineered. All an enemy ship need do is to dump a couple of rocks into the path of an oncoming ship. The victim's forward momentum will provide the necessary energy. But let's face it, the chances for any ships to detect and attack an oncoming ship are practically nil.

My best guess is that almost all space combat will take place in orbit, or else with surface-to-orbit missiles.

[snoopy369]

BP, we could easily get over .2c - it just would take a long time. Solar sails would do it with no problem (over a long time), among other things.

The reason 'turning' (ie, course correction) would kill the crew is simple - if you have a velocity vector of, say, .2c in one direction, causing that vector to be even a degree off takes a tremendous amount of acceleration in the perpendicular vector. A missile (unmanned) could do that easily, and then some, but even 100g would crush a human like a cotton ball - I don't have the time to do the math but I imagine it would take many hundreds of g's to turn a few degrees at .2c ...

[rah]

It all depends on how much warning you have that you need to alter your course. With enough warning the smallest of changes will be enough to change where you would have been far in the future. It will be a war of calculations.

Missles I would expect would be the weapon of choice due to the issues already discussed.

But due the speeds involved in space travel I would expect encounters to last less than a minute if that. Two ships travelling in oposite directions wouldn't be in effective range for very long.

[Colonâ„¢]

I'm pretty sceptical about the whole concept of crews in space combat, considering there's already something like the UAV.

[Naked Gents Rut]

Besides, the Spacing Guild will ensure that space combat is impossible thanks to its monopoly on interstellar travel.

[DanS]

There will always be space pirates.

[Zkribbler]

Originally posted by DanS
There will always be space pirates.

This is probably how space combat will begin. Freighters travelling from the moon, Mars or the asteroids to Earth, and rogue ships jumping them. Then law enforcement ships will be sent out to intercept the rogues.