I'm continually amused by the space battles in Star Trek. Two ships pull up within a few ship-lengths of each other, then lob torpedoes and phaser beams at each other. I seem to remember seeing in the old series something about how the phasers really get fired: Kirk gives the order, the weapons guy on the bridge presses a button, a buzzer or something sounds down in the "phaser room", and a guy down there presses yet another button which does the actual shooting. Similarly for torpedoes, except I seem to remember seeing them manually loading torpedoes into the tubes like it's a 1940s U-boat or something.
Vernor Vinge's "Marooned in Realtime" has some very interesting space battles, based around the single conceit of "bobbles": impenetrable force shields which essentially separate their contents from the universe (and from time) for a pre-selected length of time. Space battles then become a tricky game of trying to catch your opponent when he's un-bobbled, while at the same time avoiding the bobbled nukes and other weapons he has strewn around when you were last bobbled.
Not to mention how the oposing force's crafts are always orientated in the same plane. Very rarely do you get someone attacking from 'above' I've never seen the Enterprise upside down, as ~I recall.
If I recall right, Kirk maneuvered vertically in the Wrath of Khan. A quick google search points out Spock saying, "His pattern indicates two-dimensional thinking."
> For a ship in the water, drag increases as the cube of speed...As your speed increases, your drag increases exponentially...
He's being inconsistent.
I've actually heard this a lot lately -- people will say something is "increasing exponentially" (i.e. has a curve of the form f(x) = k*b^x) when they really mean a much looser condition like "accelerating" (positive second derivative, which might be an exponential curve, but also might be one of many other curves, e.g. any polynomial of degree >= 2 with nonnegative coefficients).
It's almost as bad as people who talk about the "least common denominator," but that's a rant for another post.
I'm tempted to say that it's good enough for something where the reader won't need to do actual math with the information. He's just trying to get across the point that the drag increases faster than linearly. "Increases polynomially" would be more correct, but would get the message across to fewer readers. "Exponentially" is inaccurate, but conveys the message more accurately than any other phrasing that readily comes to mind.
And I'm tempted to say that what distinguishes math from most other forms of expression is precision, and if you're not going to be precise, you should avoid blatantly mathematical language.
The definitive source for information about realistic spaceship combat is the Atomic Rockets web site. The webmaster set it up specifically to help authors get it right, since those are the type of SciFi books he likes to read.
I recommend the Honor Harrington novels for "plausible" Sci-Fi combat scenarios. Over the series of novels, the style of space combat changes dramatically multiple times as factions develop new technology, strategies, and tactics. They're quite a fun read.
Well the science was deliberately concocted to allow for the recreation of naval sail sea battles (ships that can only shoot "broadsides" because of the physics of the propulsion system, for example), but it was so well done that I didn't care (in fact is was rather fun).
You can buy the later hardcovers and get a CD with the entire series on it. I do recommend Baen for books because they sell at pocket book prices and have no DRM.
Gwern Branwen has a well-researched essay about more realistic space warfare: http://www.gwern.net/Colder%20Wars . His main conclusions are that planets have overpowered detection and defense capabilities against ships, but are underpowered against asteroids flung at relativistic speeds.
The interesting thing about warfare portrayed in fiction is that it's not only a very idealized model of warfare but it tends to be based on a zeitgeist which is easily decades if not centuries out of date.
For example, modern naval warfare, setting aside aircraft even, is of the sort where the combatants generally fire missiles at each other across the horizon (or would be, if there was any significant amount of naval warfare between first world powers). However, in scifi space battles you have warfare which tends to look more like naval battles in the 17th century than anything else. Inaccurate weapons. Point blank ranges. Etc. That sort of warfare was obsolete over a century ago. And even the close cousin in the form of long but still within visual range battleship battles were very rare even during WWII and terribly obsolete after that (the Falklands war being a decent example).
The idea that a laser at a range where the enemy is visible with the naked eye is going to miss is ridiculous. Similarly, the idea that any missile fired would not be guided, or that a guided missile would miss at such close ranges, is equally ridiculous.
But, SciFi isn't about predicting the future so much as it is about setting up a premise with which to tell a story, so I can forgive these shortcomings.
Not only zeitgeist. But portrayal in fiction requires heroism, action, and suspense. You don't get that with real warfare. Being shot at by an enemy you can't even see and then calling in an air strike at the location where you expect the enemy to be is not the "romantic vision" people have about war. They want close combat with sweaty men fighting each other in heroic ways.
What would be a more realistic portrayal? A bunch of automated drones fighting each other. Space even removes a lot of tactical elements. So the one who has the right number of good enough drones wins. That's boring. No heroism, no action, no drama, no suspense.
The sweat and suspense is left in non heroic and to outsiders a bit boring fashion at the engineer's drawing board.
This is one of the reasons I like Iain M Banks' space-fights, no matter the other flaws: yes, they're a bunch of drones fighting, but those drones are as entertaining characters as the flesh-and-blood passengers.
Add in no sound in space, no seeing lasers from the side, battles where you can't visibly see your enemy, ships going 'dead' without much visible going on - there's nowhere to 'sink' if you're catastrophically holed, and vehicular explosions really aren't that common despite what movies would have you believe. If you want 'action', there's not a lot of breadth in a realistic depiction of a space battle.
Ah yes. If you allow canonical, stereotypical battles then there's a high risk they could be boring. So you have to either figure out a way to portray them that aren't boring or you pick situations that are unusual to portray.
As a case in point, consider the way submarine combat is portrayed.
Submarines are a good point. But with submarines you have the whole hide&seek thing going. That's a lot of suspense right there. However in space there is no hide&seek. The problem is that space is so huge that unless you assume really fast spaceships there is no way of hiding. Planets and moons are too far apart to be really used as cover or tactical element.
Hide and Seek can work in space, even without magical cloaking technology. Space is very big, so if you're far enough away it may be difficult to tell a (properly designed) ship from random rocks or man-made debris unless you're looking dead at it already. Especially if you're flying in an area where lots of debris is already present, like an asteroid belt or a planet's ring. Doing it in near-earth orbit might be tricky, though, since people watch the sky a lot. Information from ground-based tracking stations could be used to identify large unknown orbiting objects.
What about the heat given off by the ship?
http://www.projectrho.com/public_html/rocket/spacewardetect....
Quote: "If the spacecraft are torchships, their thrust power is several terawatts. This means the exhaust is so intense that it could be detected from Alpha Centauri. By a passive sensor."
True. However, the spacecraft would still be radiating heat for quite a while, as I suspect the primary method of heat dissipation would be radiation. I suppose the spacecraft could carry some form of coolant, and eject it once the engines are shut off, but then the spacecraft would need to eject it while it is very far away from the enemy craft lest the enemy detect the ejected hot coolant. But then the spacecraft could not alter its trajectory, and so it would have to rely on the enemy craft keeping a constant trajectory.
> Hide and Seek can work in space, even without magical cloaking technology
You put the high-power components of the ship at the focus of a very long and narrow paraboloid with a highly reflective interior and a special absorptive and selectively emitting exterior. The whole ship will be refrigerated, with the radiator at the focus of the paraboloid. Then, all you have to do is to aim your thermal emissions in a direction your enemy isn't -- which is easy to do if your enemy doesn't have stealth.
Hence, stealth will exist, but primarily as a deterrent to keep your opponent from using stealth with 100% confidence.
We currently have a lot of technology to spot objects in space. As cli already pointed out there is the heat signature of any ship. Combined with radar it should be easy to detect ships from far away. In open space there is (probably) also no stable debris you could use. Asteroid belts are actual nothing like in the movies. There is a much bigger distance between each asteroid in the belt. http://www.scienceadviser.net/2009/09/asteroid-belt-not-as-d...
Maybe the ring of a planet would work. But then the ship is at risk of being damaged by the ice and other things in the ring. And of course there are only few planetary rings compared to the rest of space.
Not all scifi space battles. Just the battles in bad scifi.
Movies seem prone to this. I suspect because making what we think will be realistic space combat visually appealing and easy to follow would be super hard.
Fiction that gets space combat right (off the top of my head) include Stirlings 'Stone Dogs', and Vinge's 'Deepness in the Sky'.
Vinge's Marooned in Realtime has some neat ideas for space combat too.
I think that Niven and Pournelle's book The Mote in God's Eye had some interesting ideas. As I recall, space combat involved spherical vessels pouring energy into each others' shields with heavy lasers. The first one to overload the others' shield won.
The jury's still out on that one. Van Ripers strategies involved such things as using motorcycle messengers (without accounting for the added latency to information exchange) that were invulnerable, and his proposed ship-to-ship missiles were way too large to fit on the vessels he used. It's too complex a case for me to understand fully, but it's clear that Van Riper totally underrepresented the disadvantages of his low-tech methods.
Many of my friends believe a) submarines still have deck guns and b) warships at sea still fight by drawing alongside and attempting to board. And these are the military enthusiasts!
a) This is funny because even surface ships don't tend to use large guns as weapons except under specific circumstances. Other than torpedoes, modern submarines use guided missiles for attacking land targets or other ships that are out of range of their torpedoes.
b) Interestingly enough, this is probably the most dominant form of naval warfare in the last decade or so, due to the increase in piracy off the horn of Africa. Of course, this isn't the way things go down when warships are on both sides.
>But, SciFi isn't about predicting the future so much as it is about setting up a premise with which to tell a story, so I can forgive these shortcomings.
So true. It pains me how often I see SciFi, particularly older works, judged on the in/accuracy of "predictions".
A missile would probably be seen long before it reaches its destination and could be shot down. There's no way of hiding in space unless you develop some sort of cloaking device.
"Aircraft carriers in space" makes sense to me. I assume that warping space requires a lot of energy that requires huge reactors that don't fit in small fighters. They would depend on a "mothership" for long range travel.
Here's an example of how generalizing space-combat is difficult. The nature will depend on technological capability, extremely so. For example, if you can shoot missiles at, say, 10km/s that leads to a different type of combat than if you can do so at 100km/s, or 1000km/s, etc.
Highly relativistic missiles, at say 0.98c or more, are effectively impossible to defend against, and massively potent. At that speed a kinetic "warhead" massing only 10 milligrams (perhaps a millimeter in diameter or less) would have an explosive yield of nearly a kiloton. More so, when the missile is 15 million kilometers away (40 times the distance from the Earth to the Moon) the time between when the target detects the missile and impact is only one second.
Even at technology levels far below that level missiles can still remain extremely effective. At long distances (thousands of kilometers away) the missiles would engage in evasive maneuvers to avoid being shot down by speed-of-light weapons. And then at some point they would release a huge number of evenly spatially arranged fragments. At a missile speed of about 40km/s (which is a reasonable estimate for speeds achievable by cutting edge and next generation propulsion technologies today) you get a ratio of warhead mass to TNT equivalent explosive yield of about 190:1 (meaning that a 1 kg impactor yields 190 kg of TNT equivalent in kinetic energy). Which means that a single 500 kg missile could break up into a thousand fragments, each of which is only 3 cm in diameter (if made out of depleted Uranium) and has the kinetic energy punch of nearly 100 kg of explosives. If, for example, we imagine a crewed ship capable of accelerating at, say, 5 gees (~50 m/s^2) and we imagine a fairly small ship that is only about 100 m^2 in cross-section then an attacker could fire a barrage of only 8 such missiles and fragment at a distance of 400 km and have an effective 100% chance of at least one fragment hitting the target. Even with high powered lasers it is no small feat to destroy a 3 meter target at 400 km distance. As the speeds of the missiles go up they become more and more effective and difficult to shoot down.
But accelerating a kinetic warhead to .98c is just as much scifi as saying 'shoot them with phasors'. It's not something we can do with current or foreseeable tech (as far as I am aware).
The other thing is that the faster the missiles go, the harder they are to aim. You lead your enemy's ship and fire the missile, they make a minor course correction in the meantime, and your missile has to detect it and change its vector to match.
Space combat is one of those fun things to discuss where no matter what you suggest, someone will come along and advise you of something you've forgotten.
.98c weaponry is certainly scifi for us today, but it's possible that some time in the far future the requisite technology will exist. Although in practical terms it's probably easier to create .98c bullets than actual, steerable missiles (which is even more challenging).
However, your point about the difficulty of steering a .98c projectile is a little out of place. The point of shooting someone with a weapon that can travel that fast is that you can catch them with their pants down. Such a weapon effectively travels at 50 times the speed of light from the perspective of the target. This is because it is racing any light or signal which would give the target warning of its presence. For example, by the time a ship has had warning that such a projectile is an entire astronomical unit (the distance from the Earth to the Sun, 150 million kilometers) away it will only be about 10 seconds until it hits the ship (the light will take about 8 minutes to travel, but in that time the projectile will cover 98% of that distance, and by the time that light reaches the target the projectile will actually only be a little more than 10 light-seconds away). And such a projectile need only be a few microns in size in order to unleash the explosive power of hundreds of kilos of TNT, so you probably aren't going to detect it at all. So all you have to do is wait until the enemy is sitting in port and you blow their ship up from across the solar system.
Of course, weapons such as that fundamentally change the whole nature of warfare, so speculating about them is problematic.
"it's possible that some time in the far future the requisite technology will exist."
And it's possible that in the far future we'll be able to warp space, extract massive amounts of zero point energy, and more. In other words, I think it's a cop-out to hand wave about technology for this discussion by saying that it can be done in the future.
"The point of shooting someone with a weapon that can travel that fast is that you can catch them with their pants down."
The problem with this proposal is your target can easily solve this by randomizing the thrust enough, on the assumption that it might be targeted. Suppose you are 1 AU off and fire at where you expect your target to be in 8 minutes. The difference between 0.01g and 0.0101g is 100 meters after 8 minutes, so even a 1% difference in thrust might be enough to miss the ship. But if you're using firing things at 0.99c then your enemy can likely manage better than 0.01g.
You mentioned "all you have to do is wait until the enemy is sitting in port". That "port" is a space station, in orbit. Neptune is 4 hours out. If the station is a 1km sphere, then it only need to move by up to about 20km in any direction to make the odds of being hit be less than 1:100. Neptune is 4 hours out. 20km/4 hours is 0.0002m/s/s or 0.00002g.
For reference, the ISS orbit decays, due to air resistance, by about 90 meters per day. This is easily restored through occasional boosts. Which means that you, as the enemy, are going to need to fire off thousands of these 0.99c bullets in order to hit your target. Where does all of this energy come from?
In any case, with micron sized bullets, you're just going to drill a hole through your target. The exit hole will be pretty much the same as the entrance. Very little of the energy will be deposited into the ship, and it's not likely to take damage anywhere near to the amount of energy you put into trying to hit it.
> A missile would probably be seen long before it reaches its destination and could be shot down. There's no way of hiding in space unless you develop some sort of cloaking device.
Everyone says this, which should be a red flag. There's nothing in the physics that precludes this. You just need to redirect your thermal emissions in a direction it doesn't matter and spoof any detectors that could spot you by your occlusion of distant objects. Then it becomes a tactical problem, not a physics one.
If all of your enemy's assets in space are visible, then such stealth is easy. Then you can calculate directions to aim your thermal emissions and spoof the enemy occlusion detectors. So the only way to make stealth difficult in space is to have stealthed sensor platforms.
I think this gives rise to interesting tactical situations.
Black-body radiation is hard to aim. If you have any active systems on board, I imagine you would have to actually refrigerate your exterior to keep it from lighting up in the infrared range.
This also assumes that your enemy doesn't have observation platforms scattered throughout the solar system that can spot you from dozens of different angles.
> Black-body radiation is hard to aim. If you have any active systems on board, I imagine you would have to actually refrigerate your exterior to keep it from lighting up in the infrared range.
Exactly. A long, skinny, highly reflective parabola would do it. You'd have to refrigerate the exterior of that, too, of course.
> This also assumes that your enemy doesn't have observation platforms scattered throughout the solar system that can spot you from dozens of different angles.
No, this assumes that you have high confidence that you know where those platforms are, and that you can aim your emissions in a tight enough beam.
Also, don't discount sabotage and espionage. If only one enemy sensor is in a position to see your stealth infiltrators, then there's a single point of failure which is a good target for espionage. When the US military goes in with stealth bombers, they don't just rest on their technological laurels, they also send in elite forces to knock out radar sets. This means that the enemy should maintain double or triple redundant observation platforms. Or does it? What if their observation platforms are stealthed? Then an attacker is playing a guessing game.
Stealth in space won't be perfect, and it will be fraught. However, it will serve a deterrent purpose against other stealth. It will exist because the disadvantage of having no stealth at all leaves open a powerful game changing tool to be exploited by your foe.
I would like to think that in the future battles will have to be fought at short range because everyone's scrambling technology will be so advanced the missile needs to get there before it can be made to miss its targets.
"The United States Naval Surface Warfare Center Dahlgren Division demonstrated an 8 MJ rail gun firing 3.2 kg projectiles in October 2006 as a prototype of a 64 MJ weapon to be deployed aboard Navy warships. [ ... ] Such weapons are expected to be powerful enough to do a little more damage than a BGM-109 Tomahawk missile at a fraction of the projectile cost. [ ... ] Its expected performance is a muzzle velocity over 5,800 m/s, accurate enough to hit a 5 metre target over 200 nmi (370 km) away while firing at 10 shots per minute."
I'm sure that these hypothetical railgun projectiles have some method of in-flight correction, but we haven't forgotten how to do trigonometry since WWI. :)
I'm surprised that in all this discussion nobody even mentioned David Weber's Honor Harrington series. He tries to make his space battles as realistic as possible.
Reading the first couple of questions makes me think about how people of the late, late 18th century thought similarly about air ships and how air power would turn out to be.
H.G. Wells wrote a book called "Clipper In The Clouds" and it also used navy themes influencing how people thought it would go.
Its a movie! Its all about the story! Galactica and Star Wars have "fighter planes" purely so that the narrative can have "Heros" and "Loose Cannons". Could Kara Thrace have had her mysterious journey if she was in a 100-crew missile cruiser? Could farm-boy-done-good take out the death star in even the millenium falcon - and would we care? And then there is Galactica itself: the lost ship, the fortress in the wilderness. I'm sure my literary friends could tell me the specific term for the narrative role it plays the way I can tell you which Design Pattern accept(foo) belongs too. I saw Ron Moore's GDC talk and nothing in Galactica was by accident except Boomer being a Cylon.
In the future, aircraft carriers will be space ships, not naval ships. The aircraft will fly down from the carrier to conventional enemy airspace, then return to the carrier in space.
From what I know, that would actually solve some of the problems that current aircraft carriers are coming up against as enemy defense systems are currently evolving. I assume it would introduce some major new problems too, but I haven't checked the math. Anyway, it's a cool idea for a sci-fi story.
An aircraft which is running out of fuel can generally glide a fair ways before landing. It's rather difficult to gain substantial amounts of altitude that way. Even before that, an aircraft which intends to return to a low-orbit base needs more fuel in reserve, which means that ranges are shorter and aircraft are comparatively heavier than their ground-based brethren.
Nor is getting to "ground" from orbit free. You need to cancel your orbital velocity, or most of it, in order to manage a sustainable atmospheric re-entry. Sure, you can use parachutes later in the process, but they don't work in vacuum.
The article reminds me that in the early 90s there were a pair of games - Elite and Frontier - which had realistic movement in space. The first half of every battle was spent in time dilation (you wouldn't want real time) while you and your opponent accelerated to generally match vectors.
As for the 'carriers in space' thing that he thinks is incorrect, it's at odds with the rest of what he says. While he does defend his point with a function of sea carriers providing the interface between sea and air, that's not all they do. The aircraft carrier doesn't function as a battleship, the fighter aircraft do. The carrier functions as a support ship, an auxilliary, to the craft doing the fighting. Same in space. The large support carrier gets to hold the supplies, living quarters, extra fuel and so on, and the small craft contain the bare necessities for waging battle without having to lug around needless support slowing them down (remember also he talks of issues regarding mass and agility). I'm not saying that it's viable, just that there's more to a carrier than 'sea/air interface'.
Elite was released in 1984 and did not have realistic movement (Oolite, an open source game in the same vein is well worth checking out ). I think you are talking about Frontier: Elite II and Frontier: First Encounters
But the author's point is that the carrier size (as a fraction of total naval resources) concentrated in a single ship only makes sense when you need economies of scale for building a sea/air interface. And that heavy concentration in an ultimately vunerable place like the carrier is a defining feature of naval warfare.
If we could launch single air planes from tiny cruisers efficiently, there would no carriers and naval strategy would be completely different. There aren't similar economies of scale for supplies, living quarters, extra fuel, and so on.
SF is entertainment. It isn't really surprising it neglects things like officers spending time managing and doing paperwork in favor of always being on watch, or avoiding issues of supplying the ships, and other topics. They aren't fun entertainment.
Humans will build colonies off-Earth. And there will be wars there. There will be poverty. There will be starvation. There will be crime. Humans are imperfect beings. This won't mean we've failed, it just means we're imperfect.
The strategy of parasitism is the one strategy that has been around almost since the beginning of life on Earth. Any evolved system which is as efficient as possible is necessarily vulnerable to parasites and so constantly changing and adapting to repel parasites is considered to be one of the most important -- possibly the most important -- of evolutionary drivers.
But parasitical behaviour is fractal. It doesn't just happen to organisms, it happens in social structures too. Sociopathology is a high successful minority strategy and so will always handsomely reward whoever rediscovers it once it has been defeated.
And just as you can see the whole history of sexual reproduction as a response to parasitic organisms, you can see the rise and elaboration of civilisation as a response to parasitic social behaviour.
It will never go away.
(There's also the fact that we evolved as predators, and predators basically live in a strictly zero-sum world vs other members of their own species -- which has irreversibly shaped us to see things in those terms).
Vernor Vinge's "Marooned in Realtime" has some very interesting space battles, based around the single conceit of "bobbles": impenetrable force shields which essentially separate their contents from the universe (and from time) for a pre-selected length of time. Space battles then become a tricky game of trying to catch your opponent when he's un-bobbled, while at the same time avoiding the bobbled nukes and other weapons he has strewn around when you were last bobbled.