What Will Future Space Battles Be Like? | Hacker News Reader

What Will Future Space Battles Be Like?

gizmodo.com

28 pointsmhb25 comments

I stopped reading this article about two paragraphs in because it makes the mistake of thinking that a space battle would necessarily happen in human timescales.

A real space battle barring some silly fictional constraint (You can't hyperspace jump too close! The shields are just holding out! Can't fire from cloak! Etc etc) is going to be the perfect embodiment of warfare as we know it now: months of boredom punctuated by moments of sheer terror. Except replace months with years and moments with milliseconds.

I think a real space battle is likely to be too expensive to make a good narrative: in the status quo, major military powers in the United States avoid naval battles because the ships that matter cost billions, they can only afford to field a dozen of them, and they have a huge likelihood of dying to the first hit by a much cheaper missile. In space, the ships will cost tens or hundreds of billions, no nation state will be able to afford a fleet of them, and they will INVARIABLY be lost with all crew the first time they are acted on with hostile intent. The environment itself is plenty capable of killing the best the United States can produce without needing anybody chucking high velocity directed fire their way.

You might get some good `hacker action' breaking into the computer systems, though.

An equilibrium will develop.

If you want to fight an interplanetary war, your soldiers have to travel through an environment that will do to them what a wood-chipper does to decomposing animal viscera. It's unavoidable. If it turns out we can't make survivable ships, space is the ideal interdiction environment. Kill 'em out there before they can get down here.

Some areas of space (e.g. certain planetary orbits) are naturally important because they allow you to exert influence on combat elsewhere (e.g. by dropping dense objects on the enemy). So as ships become more survivable, it becomes more feasible to try and garrison strategic positions, and space battles will 'just happen' as opposing garrisons come into contact.

The cost/benefit equation of war has changed drastically since the Romans kept themselves in a perpetual state of conflict in order to fund the republic with its spoils. Especially in this century, the cost of war implements has increased rapidly relative to the possible benefits from engagement.

The Egyptians were doing that way before the Romans. In general, having enough food to feed a standing army (as the Nile provided) gives a country a big leg up in the sacking & pillaging.

That's largely because the weapons industry has been corrupted by government funding, though. I find it hard to believe that the research, development and manufacturing of the F-22 Raptor would really need US $65B, and $125M per plane, for instance.

Anything that doesn't travel at 299792458 meters per second will not be a viable weapon in space. Two spaceships coming toward each other will be hundreds of thousands of kilometers away when they start firing on each other. The time lag will be over one second for lasers, so if the two ships are maneuvering randomly many laser shots will actually miss. Kinetic weapons will take minutes or hours to get there, making them essentially useless. With missiles (I'll assume missiles are nuclear here), not only are they slow but you can also set up computer controlled lasers to fry their control circuitry. Nukes require very specific detonation conditions and if you fry the explosive material it won't explode like a conventional weapon, it will just fail.

Also, with ships punching a hole in the bottom is enough to sink one - most ships hit by a one-shot-kill missile take a few minute to do down because they're sinking, not exploding. In space, this doesn't exist. You have fuel tanks and engines, but those can be safely put at the back of the ship, and in a battle you'll just rotate your ship so that the front faces the enemy.

Consider this: an unmanned missile can accelerate much faster than a manned spacecraft, so it can evade laser fire much more effectively as it approaches the enemy. At a critical distance it launches its payload: hundreds or thousands of tiny (e.g. 10 gram or so) fragments distributed in a grid (at a density of, say, 1/m^2 distributed over as much as a km^2 at the interception distance). These intercept the target at 10s, 100s, or 1000s of km/s. Such a weapon is hard to defend against, even with highly effective lasers, and is devastating to the target.

I would imagine that depends a lot on what the distance is. Release too close and you get blown up by a laser before you can release. Release too far and by the time they get there the ship will have moved away.

The missile will be smart enough to compensate for ship movements.

I don't mean the big missile, I mean the payload that InclinedPlane's strategy described - a missile shooting out a few thousand mininukes a short distance away. Such small payloads, even if we give them engines (which also makes them shine brightly to anti-missile lasers) are simply too small to outrun a ship - small engines tend to be very inefficient and slow.

Another consideration this article doesn't seem to touch on: Heat.

Particle-beam weapons especially, but also anything carried by a ship that generates significant energy that isn't thrust, is going to generate a lot of waste heat, due to those blasted laws of thermodynamics. Where does all that heat go?

Yes, space is very, very, cold. But vacuum is about as close as you can get to an ideal thermal insulator, so if you want your imaginary warship to be spamming giant lasers like a Gradius boss, you're going to need some way to rapidly dispose of heat before your entire ship cooks like a P4 with no heat sink.

You could put some water or other substance and have it swimming around the ship and when you use weapons or engines send it through them and fire it out the back of the ship. It's a limited supply, but so is whatever is powering the engines and lasers in the first place.

I'd say a bigger problem would be time to target, in one of two ways:

- light speed; being 0.5 seconds away from the enemy moving at orbital speeds means that even the slightest change in direction would put you quite far from where he thinks you are. I'd guess in-combat ships would continuously change direction by minute amounts.

- old fashioned "see the bullet 1000 km away and dodge it".

This leaves one obvious option: autonomous scatter pack missiles. They would get as close to the target as possible, then split into several parts so as to be harder to pick up by laser or kinetic defenses. Payload could be anything, but i'd guess delayed explosives might do a fair amount of damage.

Don't think of changing direction, think of changing velocity. Space is a Newtonian movement system, so accelerating 20 meters per second in some direction is just as easy at 0 km/sec as it is at 10000 km/sec.

As for missiles, I really don't like the idea. If I were tasked with building a 22-nd century warship, I would put a few hundred automated anti-missile lasers everywhere, which would fry the missiles before any of them get close enough to darken the hull.

lets hope non-existent.

we already have militarization of space, plenty of satellites up there, are armed to the teeth. The second they find anything important up there, you'll have space shuttles armed to the teeth.

I guess it's not finding something important, but lowering the costs of launches, so that space becomes important.

I think the real question is: why would we let them get up there in the first place? I know that I, for one, would want anything that can drop bombs on me from space shot down before it can even get into position, no matter who's trying to put it up there.

http://www.projectrho.com/rocket/rocket3t.html

This is an ugly site, but it goes through a rational, technology based approach to space, and space warfare. I've linked to the space war part specifically, but it's all interesting.

It has lots of fluff from various sci-fi stories as well showing all the schools of thought through sci-fi history. I recommend you waste all day today, and read through it.

One would hope that once we reach that level of technology, we will have gotten past wars....

depends on how far in the future you'll go.

frankly I think all the "space battles" will basically just boil down to two space shuttle cargo haulers duking it out to hijack the other guy's shipment

This analysis is grossly naive. It notes the importance of kinetic kill in space battles but ignores utterly that the nature of the battlefield depends greatly on the nature of technology. As increasingly advanced propulsion technology makes feasible the next higher level of closing velocities (from 10-30km/s with chemical propulsion, to 50km/s with Nuclear Thermal Rockets and such-like, to 100km/s, 1000km/s and beyond with Orion, NSWR, fusion, pumped light/mag sails, etc.) the nature of battle changes. This is a far more complex topic than this overly simplistic article could ever hope to cover.

I'd read your article.

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