The Physics of Space Battles 470
An anonymous reader writes PBS' It's OK to be Smart made this interesting video showing us what is and isn't physically realistic or possible in the space battles we've watched on TV and the movies. From the article: "You're probably aware that most sci-fi space battles aren't realistic. The original Star Wars' Death Star scene was based on a World War II movie, for example. But have you wondered what it would really be like to duke it out in the void? PBS is more than happy to explain in its latest It's Okay To Be Smart video. As you'll see below, Newtonian physics would dictate battles that are more like Asteroids than the latest summer blockbuster. You'd need to thrust every time you wanted to change direction, and projectiles would trump lasers (which can't focus at long distances); you wouldn't hear any sound, either."
In space (Score:5, Insightful)
no one can hear you explode.
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Unless they use laser mics or some equivalent technology.
Which would probably be a good idea for situational awareness.
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> no one can hear you explode.
Of course they can...if someone is sufficiently close and the shockwave hits a reverberating surface containing an atmosphere that can transmit the resulting sound waves to your auditory sensor. The TIE Fighter sounds were ion streams (from their engines) hitting the hull. That's how close they got to the Falcon!
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Re:In space (Score:4, Insightful)
But there would be an atmosphere of sorts or are we forgetting that an explosion is basically a chemical reaction that releases energy and gases rapidly?
That mass has to go somewhere and some of it will be condensed enough to be an atmosphere before it dissipates.
Boooooring! (Score:2)
The reason no one does realistic space battles in movies is that they would violate people's intuitions just to be incredibly boring, at least if you're trying to show the battle. On the other hand, it would be easy and require little/no cgi to actually make a realistic space battle video, but you'd definitely want to focus on the humans at their consoles rather than on the battlefield. It would be little different than a submarine combat video, I would think.
It seems to me... (Score:5, Interesting)
If you're going to swallow the idea of FTL drives, tractor beams and shields -- among other things -- then it's not really that much of a stretch to swallow the idea of inertial control, too. Which would make such battles not resemble a game of asteroids at all.
As for sound, presuming your vehicle maintains atmospheric integrity, you'd hear anything that causes the the craft's atmosphere to be jolted into motion. Debris hitting your vehicle, the stress caused by a sealed compartment being ruptured, people screaming when they get fried, crushed or otherwise insulted as a consequence of direct or indirect battle damage or loss of, for instance, inertial damping, equipment failures and power supplies having problems. You would also hear something if a force field of any kind was imposed upon your vehicle in such a way as to deliver any kind of uncompensated-for energy in mechanically coupled framework(s) producing direct or indirect vibrations in the audio range. And furthermore , presuming a ship has sensors to detect things like the energy outputs of other vehicles as they maneuver, seems to me that converting that to audio as a handy sound cue/warning would be hardly any trick at all. Just as one example.
Likewise, perhaps *we* can't focus a laser today, but that's not an inherent limitation of lasers even by today's known physics, that's a limitation of our technology, so that objection is kind of dead on the doorstep, so to speak. Not that a visible future beam weapon is necessarily carrying its punch in the form of light anyway. Could be just a side effect, or an aiming aid. This is the future, we're talking an imaginary scenario resulting from science and technology we don't presently have and so may speculate upon (using current knowledge... pretty boring... we can barely get off the planet's surface, much less engage in space battles... that's why most SF has at least a few pure fantasy elements in it.)
And along the lines of what we accept and what we don't, if you are blase' about the idea of a magic camera floating around your space battle and instantly changing perspective from A to B to C, perhaps it's just a little bit silly to complain about, for instance, a whoosh, or what "lasers" can do. That's entirely outside of what might be realistic in terms of what the movies subjects are up to.
So yeah, it's ok to think, but don't let someone else do your thinking for you. If there are space battles as depicted in most SF(fantasy) movies, the rules as we know them right now have long since been trashed, so there doesn't really seem to be any reason to worry about it.
All of the above is why I can really enjoy Star Wars, Firefly, Trek, etc, btw. Even though I'm fairly well grounded in how we think things work at present.
I have more trouble with obvious errors that don't take into account technologies we already have. For instance, in Red Mars, some of the characters "hide" from satellite surveillance by moving over long distances in a large hollow rock (or perhaps a thing that looks like I rock, I forget), something we would spot in an instant *today* by the simple expedient of image subtraction; Take two shots under the same or similar conditions but separated by time, align them, and subtract them. Everything that's in the same place turns to black; anything that has moved will be bright. This is *trivial* surveillance technology, and has been in use since *at least* the 1970's. And the kicker is this would work even better on Mars than it does here -- thinner atmosphere. Caused me a few snickers, that one did.
Re:It seems to me... (Score:5, Insightful)
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Umm, just no. Remember that maneuverability implies a change in momentum. Good luck changing that orbital plane - you have to change the orbital momentum. For example, setting up an orbit perpendicular to the one you currently have requires you to shed all of your existing orbital momentum first.
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Launch three identical, reasonably sized chemically propulsed spacecrafts into 300km orbits in KSP. Launch them into orbital planes spaced 120 degrees apart. Your goal: dock all three together. Use mechjeb [curse.com] and dpai [curse.com] if you wish. It'll dispel any such myths in one evening.
Re:It seems to me... (Score:5, Informative)
Likewise, perhaps *we* can't focus a laser today, but that's not an inherent limitation of lasers even by today's known physics, that's a limitation of our technology
I'm pretty sure the video author is not aware of it, but that's actually a limitation of physics, not of laser technology. The fact that you cannot focus a laser at long distances is related caused by momentum-position duality in quantum physics: Laser is basically a bunch of photons going all in the same direction, with the same color and coherent phases; technically with the same wavevector. However quantum physics dictates that there is going to be a certain spread, uncertainty, in the wavevector of each photon. This uncertainty is inversely proportional to the size of the chamber where the laser was initially pumped, namely the size of the laser gun.
It is really quite similar to projectile weapons: The longer the barrel, the more accurate the shot.
Re:It seems to me... (Score:4, Interesting)
While lasers don't self-focus in vacuum, in gases, though, laser beam self-focusing actually a problem! Yeah, when you have a beam of sufficient intensity in air, it'll self focus and stay that way until its intensity decays below the self-focusing threshold. Non-linear effects FTW :)
Re:It seems to me... (Score:5, Informative)
Likewise, perhaps *we* can't focus a laser today, but that's not an inherent limitation of lasers even by today's known physics,
In fact we can focus lasers to within the limits imposed by physics. That is diffraction limited optics and Gaussian beam optics [wikipedia.org]. Real lasers and optics get very close to these limits.
Long story short its all about the size of your laser, or rather aperture. Lets assume a 500nm laser with a 1 meter wide aperture and we assume we want a spot size 1 meter or less. From the math that means we can focus that good out to a range of just over 3140km. In the middle the beam size is about 70cm. At a range of 4700km the spot size is about 2meters. These ranges scale with the square of aperture size with the caveat that we only focus to the aperture size. So a 2 meter one has 4 times the range where the spot size is 2 meters or less. It is also proportional to wavelength.
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Yes and no. Yes, right now, as far as we know. Hints otherwise, however, do exist. [wikipedia.org] Further, apparently, space -- being nothing -- can expand and contract much faster than the speed of light (see most cosmological theories), and since the distance from here to there in astronomical terms is essentially created by space... it may be that the speed of light is constant, but the space it travels though, isn't.
Also, we may discover something else. I'm perfectly ok with not being certain; I think assigning absolu
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They do - perhaps not in the way you'd tend to think - but man, they most certainly do. All of the laser energy for various laser fusion experiments is channeled through fiber optics and mirrors. You have either internal reflections in the fiber optics, or surface reflections on mirrors. And they route what, gigawatts these days? All going through multiple reflections.
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It'd be easy to counter the shoebox-drone missile group - set off a nuke. The blast would vaporise most of them and destroy the electronics or control surfaces of the rest.
That's the thing that no-one cares for in space battles, distance. No-one in their right mind woudl fight close-up, it'd be done at incredible distances where the probability of where your opponent is is the most important factor - simply because by the time you've seen where the enemy battleship is, it's moved and you're seeing the histo
i-war (Score:2, Insightful)
Go check out the GoG site for the two i-War games which feature "correct" space based combat.
Good old games, that were overlooked at the time.
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As I recall Elite used newtonian physics as well, augmented with a time-dilation module to fast-forward through those long boring lulls in interplanetary space.
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Ah yes, the joy of jumping into a system, turning on your engine for a week then curising for the next month before turning around and repeating the exercise (binary systems with the secondary having inhabited planets were a bitch).
Babylon 5 Starfury (Score:2, Informative)
I seem to recall that the Starfury of Babylon 5 got the physics (more or less) right.
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Kind of OT but I believe that Andromeda managed to depict laser small arms reasonably accurately also. Space battles needn't just be between space ships!
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Another series that got it 'right' I think was Mugan no Ryvius. Ships in orbit had 'passes' where they could take shots at each other when their orbits 'lined up', but otherwise had an hour between volleys and suc
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I can't say I paid too much attention to whether they got the science right on Andromeda... I was too busy being completely smitten with Lexa Doig.
Umm no (Score:2, Insightful)
Short bursts of thrust to get around? Wrong! Space is big... very big. Getting around a solar system would take days.
No fireballs in space? Wrong! Spaceship occupants need atmosphere.
Close in naval battles are a no-no? The is the distances lasers might be effective.
OK so we have long range battles... They say sci-fi lasers aren't possible but rockets are? It would probably be much easier to evade a rocket in space (a rocket that will probably fly past you at a crazy speed as it's course corrections have to
Re: Umm no (Score:2)
A missile can handle high G turn and acceleration that would kill a human, so yes, missiles would be way more effective than bullets or lasers.
Which is also the reason close range battles would be extremely rare since missiles would dictate battle range
Re: Umm no (Score:5, Interesting)
Re: Umm no (Score:5, Insightful)
Well, but consider: space is big. Detecting things in it is hard, unless they've giving off light or radiation that you can detect more easily. For example, today, it is very common that we don't notice near-earth asteroids until they're less than a day away, and asteroids are a lot bigger than missiles.
Atmospheric missiles must maintain constant thrust to keep flying, in order to counteract gravity, air resistance, and to maintain course skimming the ocean, as you mentioned. That makes them easy to spot as soon as they cross the horizon, giving you that 10-20s warning.
But in space, constant thrust is not necessary. The missile can be fired initially just like a dumb projectile, and only engage its thrust once it's very close to the target and needs to adjust course to hit it. Until that time, it just looks like a very small rock hurtling through the void, giving off very little energy, making it very hard to spot.
Even if you had radar or some other kind of active sensors to detect incoming missiles before they engage their thrusters and give away their position, the attacker could simply fire their missiles inside a cloud of other flak to camouflage them. So you can see a cloud of thousands of tiny objects coming in, but you can't tell which of them are missiles with warheads until the whole cloud is close enough that those missiles activate and start homing in on your position.
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Even if you had radar or some other kind of active sensors to detect incoming missiles before they engage their thrusters and give away their position, the attacker could simply fire their missiles inside a cloud of other flak to camouflage them.
And if it's coming in fast enough, even the flak can kill you.
That depends upon the writer. (Score:3)
Missiles travel very, Very, VERY slow (in space). Even if they are under constant acceleration.
Lasers travel very, Very, VERY fast. But they lose energy/focus over space-type distances.
So it comes down to how well the writer understands economics and what technological advances they are postulating.
Not to mention WHY there is a war in the first place if both sides have that kind of technology available to them.
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> Not to mention WHY there is a war in the first place
Why _wouldn't_ there be one? Given the ties between religious wars, ethnic strife, historical conflicts, economic classes, and control of land, water, food, and engergy, conflict is inevitable for any large group. The scale and nature of the conflict is what will be in question. Why would there _not_ be some level of warfare at anty time?
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Not in fact a bad idea. Given that there's no shock wave in space and physically directly hitting a moving target like a ship would be all but impossible, one-shot lasers on missiles might just be the way to go.
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I guess that could be avoided the same way they avoided torpedoes during WW2 - constant course changes. It would eat the fuel of your ships, but it's better than eating a missile.
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Detecting things in it is hard, unless they've giving off light or radiation that you can detect more easily
If they aren't thrusting towards you they aren't much threat.No way they'll ever hit you as long as you are continually changing course.
Once they turn on thrusters to home in they'll be easy to spot and could quite conceivably be taken down with lasers at that point (no atmosphere to cope with either). I'm doubtful they'd get anywhere near 10 to 20 seconds of you without thrust. You'd probably still h
Re: Umm no (Score:5, Informative)
Not necessarily - if you paint them black and launch them discretely (by rail gun?) a missile could coast unnoticed across the void to your apprxoimate location and only engage its engines for the final approach.
Radar is viable on Earth because the horizon is only a few dozen miles away and the area of interest is typically only a mile or two high - practicaly 2-dimensional. In 3D space you'd be talking about many orders of magnitude more power to run an broad-focus radar system with the sort of range you'd need to be useful. Especially considering projectile speeds are potentially several orders of magnitude faster than is possible to sustain within an atmosphere.
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The problem with this is that it is rather pointless to shoot a missile down in space. Not only because there is no down (which is, incidentally, the reason why it's useless, though...).
What happens when you shoot down a missile heading for you on earth? Well, it either explodes or you just destroy its body, either way, it will stop moving towards you and instead move towards the earth.
Now ponder what happens with the missile (or its debris) if there is no earth. I kinda wonder if it wouldn't have been bett
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Great on Earth. But in space, all that changes is that instead of one missile a cloud of debris is now coming at you.
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So? Put more fuel in your missile - it just has to be more maneuverable than its target, which is operating under the same constraints. Moreover on Earth missiles need to burn fuel just to stay in the air and maintain speed - in space they only need to burn fuel when maneuvering.
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No fireballs in space? Wrong! Spaceship occupants need atmosphere.
You'll only get fireballs inside the atmosphere. In space, you'll get jets.
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And bodies. As atmosphere is vented it will take the crew in that compartment with it.
Weber's Honorverse (Score:2)
I'm no physicist myself, but from what I can tell, David Weber's Honor Harrington series of novels does a pretty good job of getting the physics right. Most battles are missile duels, energy weapons are powerful, but short-range, and when they develop a means of giving missiles multi-stage drives, it changes the game significantly, as they no longer have a single burst of maneuvering speed and then come in ballistic; they can accelerate at their target, burn out the first stage, coast in ballistic for many
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he has much too much of a fascination with the French Revolution
I can't say you're wrong, but at least he does it on purpose. The series was supposed to recreate the life of Horatio Nelson (think "Hornblower in space"), and most of the physics "could be"s are chosen so that the battles and diplomacy resemble life at sea in the early 19th century. Of course, the heroine was supposed to die like Nelson did, but I think the story and fans won that battle. It probably explains why she's less present in the later books!
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he has much too much of a fascination with the French Revolution
I can't say you're wrong, but at least he does it on purpose. The series was supposed to recreate the life of Horatio Nelson (think "Hornblower in space"), and most of the physics "could be"s are chosen so that the battles and diplomacy resemble life at sea in the early 19th century. Of course, the heroine was supposed to die like Nelson did, but I think the story and fans won that battle. It probably explains why she's less present in the later books!
Oh, yes, I'm fully aware! I was never much of a student of that period in history, though (nor did I ever read any of the actual Horatio Hornblower books), so I'm afraid only the most hit-you-over-the-head-with-a-brick bits really get through to me. (Mainly the French Revolution expies, since I do know a bit more about that.)
My understanding as to what caused him to not kill off Honor in the Battle of Manticore was that it was ultimately the partnership with (I think) Eric Flint on the Crown of Slaves spino
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I'm no physicist myself, but from what I can tell, David Weber's Honor Harrington series of novels does a pretty good job of getting the physics right. Most battles are missile duels, energy weapons are powerful, but short-range, and when they develop a means of giving missiles multi-stage drives, it changes the game significantly, as they no longer have a single burst of maneuvering speed and then come in ballistic; they can accelerate at their target, burn out the first stage, coast in ballistic for many thousands of kilometers, and then activate the second stage for final maneuvering.
It's a good concept on the surface, but Weber destroys the physics with his own lust for large numbers: ships are not fighting at "short-range" of a kilometer or two... they're at "short-range" of a hundred thousand kilometers. "Long" range stretches out to tens of millions of kilometers. Of course, he has to, when he has ships that can accelerate at hundreds of Gs, and missiles that can accelerate at 96 thousand G's [wikia.com].
I love the series, but Weber's constant need to go from "a ship firing 10 missiles at a br
After working missile defense for years... (Score:4, Informative)
...I can tell you another thing about space battles: you don't see anything aside from a few tracks on a computer screen. If you have a telescope pointed in the right direction at the exact right time you see a very unimpressive and quick flash.
The ranges, timing, and velocities involved are far too great for human perception.
Re:After working missile defense for years... (Score:4, Insightful)
Re:After working missile defense for years... (Score:5, Interesting)
Well, it is hard to say about that. Ship to ship combat in space would probably be carried out by drones. The fragile meat bags inside would never survive the acceleration.
I sat in a radar site in Hawaii at PMRF staring at a screen during the tests I supported. A target missile was launched from a pad a few miles away (you sure as hell could hear and feel THAT!) and the intercepting ship (as in a US Navy guided missile cruiser, not a space ship) was a couple of hundred miles away. The launches I witnessed... in under a second the target was through the clouds and five seconds later was gone leaving just a trail. The interceptor makes the target look like an old lady trying to out sprint Usain Bolt (I am told it would be supersonic before it leaves the launch tube on the ship... but I never saw a ship launch but every sailor I talked to who did said it was very impressive for the brief moment they got to experience it - from inside the ship.)
Other than that there was nothing to see. The intercept itself was over the horizon, so it had to be "viewed" from an aircraft.
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Even an inert ship will be detected as it heats up. I can think of ways to *temporarily sink heat* but not that last long enough for closure of even interplanetary distances.
Stuff will get seen
Boring (Score:5, Insightful)
Actual space battles would be extremely boring to watch. It would all take place at such distances that nothing could really be observed very well or viewed as a whole. Assuming energy / laser type weapons, it's purely a matter of how sensitive and accurate the telescopes are that identify the enemy ships and direct the weapons where to fire. Stealth and cloaking would be where the real arms race would be.
There Ain't No Stealth In Space (Score:2)
http://www.projectrho.com/public_html/rocket/spacewardetect.php#id--There_Ain't_No_Stealth_In_Space [projectrho.com]
Project Rho explains that in detail.
If you cannot move faster-than-light then your engines will give you away every time.
Re:There Ain't No Stealth In Space (Score:5, Informative)
I read a rebuttal to that which was fairly compelling: http://scienceblogs.com/builto... [scienceblogs.com]
The equation given isn’t derived. We have no idea where they’re getting that 13.4 proportionality constant. Dimensionally it’s correct, and it’s pretty easy to derive the equation up to that constant which will depend on the sensitivity of the detector. That equation modulo some uncertainty with respect to that constant is accurate as far as it goes given a spacecraft of hull temperature T and cross-sectional area A.
I would take you through the steps of the derivation, but it would be pointless because the assumption that the hull temperature has anything to do with the interior temperature is simply flat wrong. We can prove this with a potato.
Switch your oven to the “Bake” setting at a temperature of 350 F. After preheating, put in the potato. The interior of the oven, and eventually the potato, are maintained at a constant temperature of 350 degrees. How hot is the exterior surface of the oven? Depends on how well insulated your oven is, but I can guarantee it’s a lot less than 350 degrees.
The key is the understanding the relationship between heat and energy. Put hot coffee in a thermos – the hot coffee is hot because it contains thermal energy. If the energy can’t leave, the coffee will stay hot because the energy stays inside the thermos. The outside of the thermos stays at the temperature of the surroundings. Now neither the thermos nor the oven is a perfect insulator. Some energy leaks out of the oven’s interior, cooling it down. The oven thus has to pump energy into the heating elements to make up for this loss. Equilibrium is reached when the rate of energy being put into the oven equals the rate of loss through the insulation.
For a spacecraft in a vacuum, the pretty much the only way to lose energy from the interior is by radiant heat. The higher the temperature of the outside, the higher the rate of energy loss via radiation. But the temperature itself is irrelevant, since just like the oven and the thermos it’s not necessarily related to the actual temperature inside the cabin at all. It is always and everywhere a function of the total power passing through the hull. If the temperature inside the cabin is constant, the power leaving the hull by radiation is exactly equal to the power being generated inside the hull.
So how far away can we detect a given amount of emitted power? According to Wikipedia, a telescope of 24 aperture can detect stars of magnitude 22 after a half-hour exposure. I think this is a pretty good realistic limit for detection with reasonable equipment in a reasonable time frame. Now we need to compare this magnitude to something of known power output. How about the Sun? The sun has magnitude -26.73 as seen from the Earth’s surface (smaller magnitude is brighter), for a difference in magnitude of 48.73. The exponent used for magnitude is 2.512, so the difference in power per unit area of telescope is 2.512^48.73 = 3.1 x 1019. Since the Sun radiates about 1000 watts per square meter at the distance of the earth, the smallest radiant power we can reasonably detect in our telescope is about 3.123.1 x 10-17 watts per square meter.
Our hypothetical spacecraft is radiating that power into space, evenly distributed over the surface of a sphere of radius r, where r is the distance to the detector. When that power-per-area is the same as the limit of our telescopic capability, that gives us the maximum detection range. Mathematically,
Where rho is the sensitivity of our detector. Solve for r:
So what’s the power? Well, each human on board is going to produce about 100 W just from basic bodily metabolism. Computers, life support, sanitation, and all the rest will contribute more. We might assume 10,000 watts total for a futuri
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The first problem with that is that it means you have to increase your engines to support the mass of the additional shielding.
Which means more engine heat that needs to be shielded.
Which means more heat shields.
Repeat.
The second problem w
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The first problem with that is that it means you have to increase your engines to support the mass of the additional shielding.
That latter bit wasn't part of the article, it was just my own addition. Even without shielding you can't see the exhaust through the rest of the ship. Adding an umbrella like insulator at the back of the ship would simply reduce the possibility of detection if you weren't coming at a target head-on, or if your maneuvering depended on your main thrust being adjustable in direction. And remember this is space, aerodynamics aren't a consideration. The umbrella could be many kilometers across and of a lightwei
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I'm replying to your post.
And that is the problem. You take that and assume that:
a. the exhaust will always be hidden by the ship
b. shields can be put on the ship to hide the exhaust
Lightweight is not the same as no-weight. Which gets back to the increase engines to support shields requ
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This leads me to wonder if a good space based weapon wouldn't be to just dump heat into an enemy ship and cook the people inside without worrying about punching through the armor. If you can exceed their ability to radiate heat, wouldn't that cook them fairly quickly?
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And the linked article you refer to doesn't understand the idea of directed power. If an enemy starship that is trying to sneak up on you has their terawatt engines firing in your direction, it's because they're trying to cut your ship in half. When engi
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That would be the part where they discussed whether shielding your engines would be possible. So, yeah, they do.
I think that you are incorrectly conflating those two statements. The engines give off reaction mass to
Scott Manley did a nice vid on this. (Score:5, Informative)
Demonstrating the physics of space fighters with Kerbals in them:
https://www.youtube.com/watch?... [youtube.com]
Some realistic space battles in literature (Score:5, Informative)
Poul Anderson, The Star Fox
Larry Niven, Protector
C.J. Cherryh, Downbelow Station
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David Weber's approach for the Honor Harrington series is pretty good.
In order to make somewhat realistic space battles interesting (or even possible), he postulates "inertial sump" technology as well as gravitic drives which combined make possible ship accelerations measured in 100s of gravities, and missile accelerations measured in tens of thousands of gravities. Even with those incredible accelerations, he makes the point that the tactical opportunities provided by being able to navigate in three dime
Fighters (Score:2)
I can see room for fighters if individual weapons capable of damaging capital ships are made small enough to be carried on them. Or if the cumulative effect of several fighters hitting the same target is equivalent. This makes the reasonable assumption that capital ships cost many, many times more than fighters, of course, who cares if you lose ten fighters at a milliion credits each if they take down a capital ship worth a hundred billion.
Also they'd offer advantages in terms of maneuverability and just pl
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Another thing I don't see much of in sci fi is the potential for truly massive fleets. If you're capable of strip mining giant asteroids and powering deep space automated factories with the sun, you could, given a little time, field countless millions of ships of all sizes.
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Another thing I don't see much of in sci fi is the potential for truly massive fleets. If you're capable of strip mining giant asteroids and powering deep space automated factories with the sun, you could, given a little time, field countless millions of ships of all sizes.
I knew all my Starcraft 'training' would come in handy eventually!
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powering deep space automated factories with the sun,
btw the sun is so dim in deep space that even if you managed to get 100% efficiency conversion, you would still have trouble powering factories. Some form of nuclear is more likely.
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Well by deep space I meant "not in orbit around a planet". You could put the factories well inside the orbit of Venus.
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Why not skip the ships and just have massive barrages of guided missles? They could approach from all angles, split MIRV style and fly random patterns closer to impact. If they could coordinate their behavior it'd be like trying to stop a swarm of bees.
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Ideally to stop them from being picked off at a distance you'd want to be able to deliver them at close to the target as possible, even a very fast rocket is going to look pretty slow in the vastness of space, and their visibility increases if they have to maneuver to match courses with a jinking target. The question is whether or not an autonomous drone AI can do the job any better than a human, taking into account things like information warfare and EMP pulses.
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Wouldn't they be vulnerable to blanket radiation attacks though, as well as the question of how they'd propel themselves?
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The pilots of the fighters? No pilots? Then it's just a missile.
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And if you send in an equivalent 'battleship' then you are likely risking hundreds of people. And as can be seen from wars on Earth, pilots are/were quite willing to risk their lives.
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Yeah but you might not want to nuke the planet, taking out military centres or something could be a preferred option.
Battlestar... (Score:2)
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Perhaps future laser weapons won't be like today's lasers and act more like a projectile but at the speed of light, given the recent progress in making light behave like a liquid or a crystal [photonics.com].
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I think with the "reboot" having about 5X as many episodes as the original, it's safe to say that unless someone says "Original Battlestar" they're referring to the reboot.:)
Lasers? (Score:2)
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How far away is a geo stational satellite? ... sensorimg your radar, he has 0.01 seconds time to,out,aneauver your laser shot (assuming you need zero time in aiming and reacting and firering your laser when you get the radar signal). The formular is dist = 1/2 a * t ^ 2, for evading a laser shot, with acc
To aquire such a target and fire a laser you have over 0.2 seconds lag already.
Reduce the distance to 3000km and you still have 0.02 seconds lag.
Now consider how big the acceleration of your victim might be
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Maybe, though as I recall there's a hard physical limit on how columular a beam of light you can send, even through vacuum. I believe it translates in oversimplied form to, a light beam can be spreading or "tightening", but it can't travel in a column: to get a focal point at distance X you need a lens of minimum diameter Y - and when X is thousands or millions of km Y can start getting unwieldy.
Lasers also have a problem in that they can only fire in a straight line, and thanks to lightspeed delays you're
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I think the easiest might be "learning to focus lasers a little better."
Let's take a step back.
What would provoke a battle in space? The simplest answer (at present) would be a dispute between two earthly powers vying for dominance. In that case I doubt that anyone in the general public would be aware of what was going on and the distances involved ( a few hundred km, up and down) means that ground based energy weapons and small projectiles that intercepted the opposition's orbits would be all that's needed.
But once you get into interplanetary conflict, it's a different mat
Not Humanly Possible != Impracticle (Score:3)
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Does it really matter how fast your tactical computer is when the bottleneck in performance is material limitations? A ship can only go so fast, change direction so quickly, and so on. The real problem with human pilots will be their inability to withstand enormous g-forces that a machine would shrug off, this gives automated drones a major advantage tactically speaking.
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Unexpected situations like an enemy starship might throw at you, you mean? :D Also I've a deep respect for the value of instinct and experience.
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Easy enough to beat it when it can only survive a few G's while the drones it's trying to outmaneuver can handle hundreds.
My first encounter with Realistic space battles... (Score:4, Interesting)
Periscopes (Score:2)
Why has hollywood butchered the reality periscopes in submarines? Answer that and you will have the answer to space battles depiction.
Rule of Cool (Score:2)
Space battles aren't dogfights. (Score:3)
Conservation of Momentum (Score:3, Insightful)
If you're going to have reaction drive style thrusters for maneuvering, you're going to run out of fuel very quickly, dissipating mass, unless your thrusters are thrusting out little bits of mass at VERY high speed, in which case they could be used as weapons themselves. (Sci Fi writer Larry Niven came up with the idea of a reaction drive as a weapon, google the 'Kzinti Lesson' for more info.)
I think it would be interesting to have space battles where several fighters were somehow connected to each other via some sort of tractor beam, so they maneuvered by transferring momentum between each other instead of dissipating mass into the vastness of space; they might look a bit like bolas circling each other but with quick changes snapping in and out as they went in to battle, or maybe they would be tethered to a mother ship, somewhat like World War II aircraft carrier that sends out figher planes to do the fighting. The mother ship would have enough mass to let the fighters seem to be free to zap around easily.
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("Cough Cough") I wrote an unpublished Sci Fi Novel (I did send it to a bunch of publishers at the time, over 10 years ago), where interstellar travel used 'draggers'. There was no faster than light travel so it took years and years to go between even nearby stars, (The travelers themselves would be in an accelerated frame of reference so it wouldn't be so long for them.) In the novel it took a long time to set up a system between two solar systems, similar to the way it takes a long time to set up a railway between two cities, but then you could use it very efficiently. A vessel would attach itself to a dragger, and be quickly accelerated (that's the hard part, dealing with the sudden accleration that would flatten everything against the back wall like you were in a super cream separator), the dragger, much more massive than the vessel, would be slowed down some, but then, at the other end, as the dragger wheeled around a star, the vessel would transfer it's momentum back to the dragger and slow down to become part of the other solar system.
The thing about conservation of momentum is that it means the center of mass of a closed system doesn't change. If two solar systems and the draggers going between them were a closed system, then the center of mass would shift as the vessel moved between one and the other, but, if the vessel returned to the original system again, then the original center of mass would be restored, and the energy used to move between them could be recycled, plus there wouldn't be reaction mass being spewed out all over the place.
The hardset part: finding the enemy (Score:4, Interesting)
The only two "giveaways" would be the heat signature from its power source (not just propulsion, but life-support) and whatever it accidentally occults as it moves across the background of stars. The heat can be drastically reduced by towing the power source a long way behind the main craft and having it very, very dispersed so the Watts per square metre of I.R. are very small. The occultation problem can be reduced by choosing a path that stays away from the galactic plane.
So most battles would be ones of sneak attacks and defensive fire. It might be possible to devise some sort of A.I. mines, or even simply fire a cloud of sand in the general direction (assuming the relative velocites of target + sand are high enough, that could be all that's needed).
However, I have a feeling that most "wars" in the future, whether in space on on Earth, will be economic in nature and "fought" over decades rather than wham-bam shooting battles.
More like the Paleolithic than 18th Century (Score:3)
Any colonization of Space would drop the population density. With out a dense population you cannot support a large military. So you have two scenarios, a very local one and a distant one. This is much closer to the Paleolithic then to any modern or near modern history.
The local one would be like what we have today. If everything is one polity then you have police functions. It there is more then one polity then you have militaries. The Blue and Green colonies of Mars fighting over something. What they are doing is trying to change the nature of how power and resources are controlled by the polities. This is some sort of permanent reshuffling. You have to remember that the instability of the Middle East is driven by large, poor, young, male heavy populations.
In a distant scenario you get hit and run tactics. Mars colony wants the ore that Europa colony has, so it launches a raid. Grab the ship and go. It doesn't try to change the nature of Europa's or it's own polity. This is what you see for most warfare in most of human history. This means a totally different kind of technology and tactics.
I tend to think that Firefly got it most right. Space Wars are Civil Wars and the military exists to maintain the status quo. Fighting will take place within the Polity.
Manual control (Score:2)
The most unrealistic thing in space operas is the notion that the human crew could do anything in terms of gunnery or navigation better than a computer.
Even worse is having the computer count down when to take a shot, and then have a human insert a random second or two while they manually operate the control.
spacebattles animations (Score:2)
Is there a good site for space battles animations? I used to go to spacebattles.com [spacebattles.com] but they haven't added any content in many years.
The Lost Fleet and B5 (Score:2)
My take (Score:3)
Combat ships will be largely unmanned, with several (for redundancy) manned "overseers" nearby to give the drones a sentient strategic advantage. Remote oversight wouldn't be able to respond quickly enough due to communications lag, although the overseers would be in two-way communication with more distant officers coordinating the combat groups general strategy.
Assuming the technology to efficiently and compactly generate incredible amounts of power has progressed equally with all other fields relevant to space colonization, energy weapons would be favored over more conventional chemically-propelled/detonated ordinance like bullets, missiles and bombs. Conventional ordinance requires mechanical fidelity and precision to fire, is limited in quantity to due to the mass required to be effective, travels slowly over great distances, may be easily impeded by other ordinance or energy weapons, suffers from intertia and can result in friendly fire if it is disabled, misses its target, or is fragmented by defensive countermeasure. Energy weapons reach their target nearly instantaneously, may track their target for sustained, precision delivery, and use only enough energy to obtain the desired effect. Their vector can be controlled non-mechanically, allowing sensors to maintain a lock on a rapidly and unpredictably moving target. They may not be impeded by other energy weapons and travel too quickly to be countered by dynamically-deployed mass-based countermeasures.
The precision and accuracy of combat drones' movement and energy weaponry combined with the tiered progression from automated drone to human overseer would, with the exception of any extreme tactical choices by central command, product a general lack of chaos that is atypical of conventional battles. The primary focus would be to edge out the opponent by obtaining slight defensive advantages through technological superiority, use of unique environmental factors (planets, moons, stars, gravitational or radiological fields, asteroids), the purposeful introduction of unpredictable or chaotic elements (literally gambling that the increase in chaos will be favorable), or psychological tactics such as deliberate attacks on civilians, propaganda and public (broadcast) executions and torture.
The bottom line is that less people would die. Once the enemy drones have been decimated there's really no reason to go on slaughtering the general public. Once that happens the first few times, history will keep the losers of the future in line outside of the inevitable (but manageable through surveillance and information control) insurgencies.
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Or... he could just toss that ball bearing out the airlock.
When an aircraft intercepts another aircraft, it's closing velocity is limited to between the difference of the aircraft's top airspeed (if one is overtaking another) to the sum of their top airspeeds (if they are closing head on). That's because both aircraft "want", in the absence of energy expended, to match velocities to the air they're moving through.
There's no limit (other than relativity) on the closing velocities of spacecraft, so when one
Inverse-square law (Score:3)
https://en.wikipedia.org/wiki/Inverse-square_law [wikipedia.org]
Energy weapons in space all have the same problem. The distances involved mean that they get real weak real fast.
At best they'd be useful in a fixed-site-defense scenario. Such as putting them on moons to defend against incoming ships.
But then you have the problem where your defeneses are not manoeuvrable. So asteroid bombardment becomes an option.