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The problem with "realistic" space combat is deciding what you're going to be "realistic" about. The writer dismisses the possibility that the civilization is going to be willing to spend "months" traveling around a star system, and so immediately starts off with a bunch of fanciful drive designs that have enormous impacts on ground assumptions.
In general, we really can't discuss FTL options with the word "realistic" in mind, so we're discussing STL. I'd suggest that in a single system STL setting chances are people will accept slow travel because it's much easier to build a safe, inexpensive transport system that takes months to send people from place to place.
Here's the bottom line -- communications will be at lightspeed, travel will be automated. What do you care if you're sitting in a space capsule traveling to Mars at 300,000km/h (and thus taking quite some time to get there) if you can work, play, communicate with loved ones, and enjoy "feelies" while in transit.
The key takeaway from musings like this is that, at the extreme, Newtonian space combat is very very weird, and will probably be very different from what we might expect depending on the technical details -- which are unknowable. And bear in mind that the article simply assumes symmetrical combat. What if the two sides have different technology stacks?
I should note the article also assumes spaceships with crews launching missiles. Why bother? Your space fleet would simply comprise missiles.
I thoroughly recommend Arthur C. Clarke's Earthlight in terms of fictional treatment of futurist space warfare (but it's asymmetrical).
Maybe the conflict between delta-v and acceleration leads to missiles. Interplanetary spacecraft are high delta-v, which makes them poor at evasive maneuvering. Missiles are high acceleration. For an intercept you use the spaceship for most of the delta-v, and let the missiles overcome last-minute evasive maneuvers.
It seems like a stretch to me. Accelerating a whole big valuable spaceship just to help a missile reach its target seems like a bad idea. Instead just build missiles with a boost stage.
The real problem, as always, is the hard problem of consciousness, which in practice screws all the assumptions of monkeys in tin cans.
Before we discuss drive designs, we have to understand what the limitations on travel are for us. There is a very real sense in which we could send a million space ships and not care whether they make it or not, or whether our missiles are conscious and no different from space-ships and so on.
The mass and propellant stuff works out the same, but the practical consequences are so different that it's hard to think seriously about any of these problems, when the actual problem is mind and not rocketry.
Modern war is already just missiles or guerrilla warfare and the like. The last full-scale war between two powers was WWII, before missiles and nuclear weapons.
Many aspects of the Korean War still resembled WWII warfare. The numbers fielded on each side were into 6 and 7 figures. The land area that was involved is comparable to that of major european nation states. I'd say that this was in many ways a full-scale war, "police action" moniker notwithstanding. Then again, there were limitations on the use of air power to limit escalation, so it was certainly not a state of "total war."
Exactly -- drones firing missiles and asymmetrical warfare.
Warfare has usually been asymmetrical. We're a bit biased because of emphasis on recent western wars, but historically most wars have been fought between different technologies and doctrines. And asymmetries are likely to be far greater in future.
Incidentally the US navy has been experimenting with drone submarines as torpedo launch platforms for decades, so it's underwater too.
Interesting analysis, however it complete misses the current trend military aviation of using unmanned aircraft. Why bother with heavy life support systems when a carefully crafted combat autopilot will do? It just needs to understand a mission profile and some orbital mechanics basically.
Also, what would be the incentive of investing in large, vulnerable warships instead of large numbers of inexpensive drones which could even double as kinetic missiles?
There is very little justification for human involvement in space combat. We are very fragile, and space is a harsh mistress. Not only is aviation headed towards automation, every extra-terran spacecraft that has been built has also been automated. Even if the life support systems were entirely costless, having to keep acceleration under certain limits (i.e. below the point where people turn into paste) seems like it would be disadvantageous.
To me the question of propulsion is most interesting, and specifically I wonder how feasible it would be to solve the problem of engine design by using two different engines. Nuclear propulsion looks good on paper, but a ready supply of fissile material is likely to be difficult to obtain.
Lastly we might consider whether or not space combat will happen at all. Spacecraft are very expensive, and the conditions which give rise to warfare on Earth seem unlikely. When your political entities are light-years away from each other, it's hard to have resource conflicts. Or, in a universe with FTL, it's probably hard to have conflicts when you don't have causality.
It doesn't completely miss those points, it covers them actually.
"The fighter is probably nothing more than a glorified chemical-fueled missile anyway, no more sophisticated in principle than the missiles you already expend by the dozen. You can at least double its effective range by replacing the pilot with a computer and turning it into a disposable missile bus (I say at least because the computer will probably mass a lot less than the pilot and the life support systems necessary to sustain him). It may be able to accelerate faster too, since it’s now freed from the restriction of having to not kill the pilot with bone-crushing sustained G forces."
Also this:
"This means that, unlike in many pop SF depictions, warship crews will probably be quite small. Human beings require a lot of supporting mass in supplies, life support, and crew quarters, so spacecraft in general will probably be heavily automated. A warship will probably basically be a can full of weaponry on top of a big fuel tank, with the crew controlling the thing from a small habitat module. The crew will effectively be command crew; there to tell the machines what to do, not to micromanage the operations of the ship. You’ll probably have a small core crew to fly the ship, a few damage control technicians, and maybe a medic or two. Serving on one will be more like serving on a WWII U-boat than anything else."
Makes me think you actually didn't read it.
But why even have manned warships at all? Why not control everything from home base?
I think you have to wonder why space civilizations would bother to go to war at all. Is it for resources? Space is effectively infinite. There are going to be a vast number of suns and uninhabited planets available for a very long time. Is it because of ideology? That doesn't really matter if anyone can simply move off one planet and find another.
> "Space combat will be rather like air combat: largely a matter of one hit kills."
> "space battles will be in essence drive-by shootings. The combatants will plunge towards each other at dozens or hundreds of km/s and hit each other as hard as they can as they pass by each other. If both sides are lucky enough to have survivors they may turn back towards each other and try for another pass in a few hours, days, or weeks."
Combat like this was described in Joe Haldeman's 'Forever War'[0], IIRC.
Probably the best military science fiction novel written--I'd even edge it over Starship Troopers.
Particularly sad are the descriptions of drones that follow a ship for months, years, and nail it right as it is pulling into port. :(
I really liked the book (review in German: http://www.2uo.de/the-forever-war/), but the ending was a bit too unbelievable for me.
When I get into conversations about what space combat would really be like (if it ever even happens), I usually cite this book, and summarize the combat in one sentence: "The ships are taking evasive actions for shots which will hit them in 3 months." That's usually all it takes to make them really understand that space is nothing like you see in Star Wars.
On the other hand though, Heinlein makes a good case for interplanetary war never happening in Time Enough For Love. "The second best thing about space travel is that the distances involved make war very difficult, usually impractical, and almost always unnecessary. This is probably a loss for most people, since war is our race's most popular diversion, one which gives purpose and color to dull and stupid lives. But it is a great boon to the intelligent man who fights only when he must — never for sport."
An interesting digression, but he also makes the case for why a common currency between planets is completely impractical (like was mentioned in the news a year or so ago). The entire book is a great read, and it's probably tied for 1st in my list of favorites.
I think the author is wrong on visibility. Put simply: things in space are very far away and hence visually small. You have to be looking in exactly the right place. Finding things when you know where they are is easy. Poking around randomly for things you might have missed is hard. Compare: the effort to find earth-crossing asteroids - objects that like a hostile ship are dark, drifting, and small.
>>>objects that like a hostile ship are dark, drifting, and small
Dark on the visible light spectrum, sure. But if you have active engines or live crew (or both), you will be much warmer than space-at-large. Asteroids are tricky because they're dark AND cold.
This is one aspect of Mass Effect's lore that I particularly enjoyed. They took heat into account when building the the Normandy - a stealth frigate.
It's a "stealth" ship because of two major things. Its hull's ability to deflect or absorb radar waves, and its heating/cooling exchange which was built in such a way that it can absorb heat into internal heat sinks for a limited amount of time, while cooling the exterior and engine emissions in order to reduce IR emissions.
With the stealth systems functional, you would have to find it by sight, which is hard to do.
They even discussed how the simplest way to disable many civilian craft was to disable their external emissive heat exchangers, since without them you couldn't run your engines for fear of cooking everyone inside. Warships had "tiger stripes" to limit the effect of losing one emissive surface would have on the ship's effectiveness. They also had methods of dumping massive loads of heat by ejecting molten salt (with an magic^w magnetic field collecting the cooled salt near the tail of the craft).
Asteroids aren't that cold, even. If you had a ship with a deep parabolic shield, the outside of which absorbs EM radiation and the inside of which is highly reflective, the ship could be rendered invisible outside of a narrow cone where it's directing its waste heat. It would still occlude starlight, but unless some of the enemy's sensors are stealth platforms, false signals could be generated to prevent the occlusion.
Such stealth ships couldn't maneuver much, but they could only be countered by other stealth platforms in a cat and mouse game reminiscent of Cold War submarine contests.
> But if you have active engines
Maybe the "stealth" weapons of space combat look a lot like blimps.
They use big, cold, dark tanks of compressed gas for thrust. No combustion; just spraying compressed gas for propulsion/steering until they're close enough to the enemy target.
Then and only then, they activate active engines (or fire missiles with active engines) for the attack.
I'm not sure if those physics remotely work. I guess you could at least get up to a few thousand km/hour with a decently big enough tank of compressed gas in space, when you don't have friction or drag to worry about.
I can't find it now, but I read an essay a number of years ago that fairly well convinced me that we could (using the technology of the time) theoretically build a telescope that was small enough to be mounted on a space ship or monitoring satellite (~1 meter aperture IIRC) with sufficient angular resolution to spot the space shuttle engines firing at the distance between Earth and Jupiter. We had at that time enough GPU processing power to do a full scan of the sky every 5 minutes.
Now, keep in mind that any ship bearing humans is going to need to radiate infrared photons at about room temperature, around 300 kelvin.
What this implies is that you want to be using an infrared telescope and look for whatever lights up against the cosmic background. Spaceships would be easy to spot, at least inside of our solar system.
The author mentions http://www.projectrho.com/public_html/rocket/spacewardetect...., which has a link to this from 1998: https://groups.google.com/forum/#!topic/rec.arts.sf.science/....
Me, I'm not a physicist and have no idea what I'm talking about, but I do know that if you're looking for a campfire in the desert and the desert is the size of Utah and Nevada, you're going to have a hard time.
Put the ship inside a deep parabolic cone, the outside of which absorbs EM radiation. Aim the cone away from enemy sensors. You have a stealth ship, only detectable by occlusion. However, if all of the enemy's sensor positions are known, such signals could be generated.
Conclusion: you can have stealth ships, and will only be able to counter them by blanketing the volume you patrol with sensors or by deploying your own stealth platforms.
> objects that like a hostile ship are dark,
> drifting, and small.
Excellent comment!
The only thing I would add is that I'd presume that if space was popular enough to fight over, there would be several ships flying around on several different trajectories. Between the vastness of space and an abundance of hot targets, it would not be trivial to locate another ship, especially if warships were designed with this in mind.
I assume the task would be made easier by having computers scan the space around the spacecraft through a wide range of wavelengths, from thermal to xray including visible.
We generally find near-Earth asteroids the day of their encounter with Earth. This would be all that's needed for a spacecraft to respond to a potential threat.
The author does mention that you could just shut down your engines and wait to spot your prey; but once you put yourself on an intercept (by firing your engines), the opponent will know where you are.
Fascinating stuff. I suspect there's a missing possibility on the weapons front though - huge numbers of small kinetic bullets going very, very fast. As the essay points out, you'll be able to spot the enemy from a huge distance. If you point your ship at them, accelerate to a very high velocity and then release millions of objects out of the front the giant cloud of bullets would carry on in a straight line towards them. So long as the other ship doesn't know that you've done it and change course it'll straight in to your weapon.
Image throwing a bag of sand at someone running at you. That sort of thing.
(I once discussed space terrorism with someone - they suggested a good way to hold the world to ransom would be to threaten to fly a spaceship full of sand out of the atmosphere, slingshot it around the moon, and slowly sprinkle the sand out the back effectively making it impossible to put anything in orbit again if the world didn't meet your demands.)
I read a sci-fi novel where a planet got hit by a relativistic load of sand and fried the planet due to the atmospheric heat transfer. Planets are basically screwed if you've got near-light-speed ability.
Go read Lensman series by EE Doc Smith, he has planets being used as weapons; moving at relativistic speeds.
very imaginative and good series to read.
You'll be able to see the heat bloom caused by the hot gasses escaping the enemy's ship as it accelerates and know that they're gunning for you.
At that point it's a matter of maneuvering randomly to dodge the kinetic kill munitions. Which certainly involves some luck.
I think direct kinetic weapons only work at long ranges against targets with static movement patterns - ones in regular orbits.
Spaceships can easily dodge projectiles coming from long range, as long as they're looking for trouble.
I think the better option would be some sort of missile bus that released this cluster/shotgun munition at close range in order to ensure a hit.
If there were any sort of treaties around space combat in the future, I think one of them would be a blanket ban on dumb kinetic weapons.
Only outlaws (terrorists, rogue states) would use machine-guns in space.
Interesting, but I think Atomic Rockets does it better:
http://www.projectrho.com/public_html/rocket/
Gah! I was about to post this. I remember reading that when I was in highschool. It certainly put a damper on some of my imagination... or at least made me far more aware of what was fantasy and is (hard) science fiction.
The article has a link to Jon's Law there.
The author of this ought to read a plot summary of 2312: http://www.amazon.com/2312-Kim-Stanley-Robinson/dp/031609811...
In that book, a colony on Mercury is attacked through the use of several billion pebbles that were flung into the solar system in a calculated way such that they all converge on the colony several years later and the kinetic energy they gained going down the gravity well combined with the sheer mass is a devastating attack and totally undetectable (a single pebble would just burn up in an atmosphere or be a consideration in colony design on an atmosphere-less planet like Mercury, so why monitor it? Billions of them would form a destructive plasma cloud if aimed at Earth or simply a kinetic energy weapon against Mercury).
Further, the author discounted kinetic energy weapons too easily. A rail gun in space would not have to worry about air resistance limiting the range or impact magnitude of the rail slug, and so would be a very effective weapon in ship-to-ship combat (or more likely, railgun installations on satellites aimed at the intruding ship).
Taken together, I think space warfare wouldn't involve ships as we know it at all. It would be planets firing at each other similar to ICBMs between countries today, with drone-like mobile weapons platforms with stealth that are launched as part of commercial launches and placed via gravity slingshots (and so can be as cold as space until an activation signal is sent to it, allowing stealth tech to actually work). These would be placed near potential enemies and probably allies alike, and would be used both offensively and defensively: if an enemy makes an open attack, they would target the attack itself, if they attack, it would reduce the potential response time, though it could not be as significant in magnitude as a massive attack launched from the planetary surface.
(Warning: The book is really not a good first one to read from Kim Stanley Robinson, as it explores some of the more esoteric elements of the Mars Trilogy even further, with a focus more on how technologies of all types, especially bioengineering and artificial intelligence, would affect societal norms, and is far enough away from our current norms that it'd probably "gross out" people ill-prepared for it. Better to read the Mars Trilogy first and follow the line of reasoning that produces the kind of society in 2312, I think.)
This was very interesting and well thought out.
I thought of another attack vector: systems disruption - hacking, if you like. It has the advantage of working at the speed of light (so being easy to aim), energy efficient, and relatively hard to defend against.
At the crude end of the spectrum we have blanket 'denial' attacks: flooding the enemy ship with huge amounts of EM radiation aimed at knocking something important out. Idea here is that while lasers do much the same, they work simply by melting the hull. Using other frequencies may present the opportunity to selectively overload important systems, zap internal electronics, or disrupt sensitive and hard to shield components like targeting sensors.
More refined approaches might involve penetrating shipboard networks using the enemy space navy's command & control infrastructure. There's no need to describe the arms race of exploits & countermeasures which would result.
There is a fundamental problem imagining space "combat" in that cheap WMD-ish "space junk" weapons that deny access to space would dominate any space war scenario due to the likely asymmetry of war in space. That's going to be true for the next few centuries.
Interstellar travel implies access to plant-scorching amounts of energy, and that, again, puts warfare into MAD WMD territory right off the bat. War will be short, genocidal, and boring in a realistic vision of the future.
Hard science fiction inevitably leaves behind many aspects of today's life, including current and merely extrapolated ideas of warfare and military power. That's what makes it interesting and difficult. That's also what makes pseudo-hard science fiction unsatisfying.
Space is absolutely huge. Scarcity of resources is a trivial problem compared to travel. That is, the odds of a finding a commercially viable alternative source of whatever element or small molecule or even habitable systems is wildly less expensive than war. Why bother fighting? The only consideration would be a situation where one civilization is so overwhelmingly more powerful, the annihilation of the weaker is trivial, like stepping on an anthill. Except the odds of your foot ever landing on an anthill approaches nil.
Don't cross the street to get your ass kicked.
The essay mentions deploying cheap infrared detectors in a variety of orbits, to eliminate stealth.
Well, each of those detectors is also a space mine and/or missile. Wrap them in black velvet. Make their power supply a dual-purpose radioisotope battery and nuclear bomb. Space combat essentially becomes swarms of exploding robots trying to destroy each other, such that the attacker can get a relativistic kinetic missile to the significant target without being intercepted and deflected.
There are no capital ships, no fighters, no scouts, or anything of the sort. You just have clouds of smart missiles trying to influence the targeting of the planet-killing rock.
Also, where were the "sand shotguns"? It's fine to consider missile swarms that overwhelm your target's missile defenses, but if you throw a trillion micrometeorites at your opponent, he's going to have a bad time. Besides that, it is also reaction mass, usable for maneuvering your own vessel.
I think the article miss a big point: why war it will be?
In term of definition of objectives mainly. If the objective is to exterminate another civilization, why not just launch an infinite number of small vessels that will crash on planets, space station and space ships? If it's controlled by an IA, who cares? the only thing which will matter will be economical sustainability.
if the objective is to take control of a planet or a solar system, you are going to need big vessels, troops and other SF concepts. But I don't think anyone will care to take control of population. They might care about ressources and installation. Everything is so fragile, that it wont make any sense to try to gain control of it, the odds that every will be value-less at the end of the fight are simply to high!
I was really impressed by The Lost Fleet's detailed exploration of space combat - http://en.wikipedia.org/wiki/The_Lost_Fleet
I agree with the notion of unmanned drones as missiles. Launch a few dozen of those in orbit and activate them when needed. In interplanetary situations, I see launching missiles days if not weeks before actual orbit intersection, so acceleration is not a factor, but rather it will all depend on your available delta-v. I think playing with Kerbal Space Program will give you a better intuition in addition to combing through atomic rockets.
One thing that wasn't addressed was space junk accumulating around planets because spaceships were blowing each other up. Unless the ships have really think armour or shields, planets would not the place to have space battles.
An interesting scene I ran across in the novel Leviathan Wakes was two planets' miltaries trying to get control of asteroids suitable for dropping on each other's heads. That felt credible to me.
There is one exception I can think of: a Q-ship. You take a merchant ship, fill its hold with missiles, and put launchers and other weaponry under hidden blow-away panels on its hull. Of course, it’ll probably have significantly inferior performance to a real warship, since it has a merchant ship’s engines and hull. And it’ll only work once or twice, until the enemy starts demanding merchant ships submit to inspections before they get within weapons range of their important facilities.
Once is enough. The Soviets annexed Czechoslovakia with civilian airliners on scheduled flights full of heavily armed, bloodthirsty Spetsnaz. Once you get a foothold you can bring in reinforcements at your leisure.
I believe a Q-ship refers specifically to the use of fake merchant ships to draw would be attackers in and destroy them with the element of surprise. Would the Soviet/Czechoslovakia strategy be more aptly described as a Trojan Horse?