Aurora 4x
VB6 Aurora => Newtonian Aurora => Topic started by: bean on October 13, 2011, 07:23:29 AM
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As for cannot hide in space... yes, you are correct. The ship definitely will have a exhaust plume in Aurora of some description, since it has a Thermal signature. BUT... even so, I like the current system. This is a point where gameplay and fun should trump realism.
That's why I'm asking for it as an option. Not everyone wants it.
Back to minefields... the way Stars! worked was that if you lay minefield then any enemy ships passing through that exceeds a certain speed risks a % chance per turn of striking a mine. You can go slower to be safe and detect mines soon enough to avoid them. This suggests to me a VERY sparse dark minefield, and is something that can be considered for Aurora. From the comments I see others agree that mines will tend to be point denial instead of area denial, hence me thinking of ways it possibly can work as area denial. Possibly when laying them they will have a sparsity setting? And perhaps a one-shot laser warhead, allowing them to hit from range instead of having to make physical contact, or else engines that activate when close enough after which it acts as a missile. If you make the minefield VERY sparse you might even be able to seed the whole system, but it would require that the enemy be fast and even so only get hit a few times as it crosses the system. Non-newtonian materials and gravity manipulation can explain how they can keep a position in a system without being limited to an orbit or a lagrange point.
Given how vast space is, in general, a mine with longer range will be more efficient for a given cost. I can run the numbers later, but I fail to see any case in which a low-range weapons (which includes unguided kinetics and laser mines) is efficient. Plus, using missiles avoids adding new elements to the game.
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You can hide in space.
You might not be able to hide in an open space, but you can mask a thermal signature next to a star or planet, not perfectly, but hiding is not invisibility, it's uncertainty.
As long as your signature is confusable with the heat emitted from a nearby stellar body, the enemy will either not be able to know for certain you're there, or risk shooting at false contacts.
Next to a Black hole, Pulsar, or in a Nebula ships might even be able to mask their EM presence, if that environment doesn't kill them.
Which brings up another option, hiding in the crowd.
Buzzers might emit heat and other radiation to fool passive sensors.
With what amounts to a fridge, it could also be possible to cool the outside hull of the ship and emit heat the other way, to hide in an asteroid belt for a short time, it would give a heat emission, but again not a valid target.
You might call none of those hiding, but the application comes pretty close.
As for minefields, given that Aurora is 2D, theres a much higher chance of using those correctly.
In an environtment like this, you could use mines not as denial, but delay; Knowing the systems an enemy fleet might come from, putting mines there would require them to come in more slowly and then maneuver, or jump through another system; all of this increases delay, and thus uncertainty, making attacks more risky.
Btw, excellent read!
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With what amounts to a fridge, it could also be possible to cool the outside hull of the ship and emit heat the other way, to hide in an asteroid belt for a short time, it would give a heat emission, but again not a valid target.
This is a Very Bad Idea (TM). Internal heat is hard enough to get rid of in space, a system designed to do the opposite is lunacy. Not to mention, the main problem is not ambient heat, indeed, to be indistinguishable from random debris it should be left unaltered; the issue is the excess heat from inside which must be radiated or stored inside somehow, and radiated later.
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I wouldn't say lunacy, I would assume a ship built for this would be able to mask their presence at least for a bit. Which actually would make hiding rather more interesting. Say they can only restrict emissions for 6 hours or so before they have to vent, it becomes somewhat tactical in that you can't just pop into cloak forever.
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I wouldn't say lunacy, I would assume a ship built for this would be able to mask their presence at least for a bit. Which actually would make hiding rather more interesting. Say they can only restrict emissions for 6 hours or so before they have to vent, it becomes somewhat tactical in that you can't just pop into cloak forever.
Yes, but what was being proposed was not restricting emissions, it was using a fridge on the outside of a ship.
There is a marked difference; one requires a heat pump to reduce the temperature of the outside, and dumps all of that extra heat plus the waste from moving it, back inside.
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You can hide in space.
You might not be able to hide in an open space, but you can mask a thermal signature next to a star or planet, not perfectly, but hiding is not invisibility, it's uncertainty.
As long as your signature is confusable with the heat emitted from a nearby stellar body, the enemy will either not be able to know for certain you're there, or risk shooting at false contacts.
Next to a Black hole, Pulsar, or in a Nebula ships might even be able to mask their EM presence, if that environment doesn't kill them.
Which brings up another option, hiding in the crowd.
Buzzers might emit heat and other radiation to fool passive sensors.
With what amounts to a fridge, it could also be possible to cool the outside hull of the ship and emit heat the other way, to hide in an asteroid belt for a short time, it would give a heat emission, but again not a valid target.
You might call none of those hiding, but the application comes pretty close.
First, read the link I posted. It goes into more detail then I have time for.
None of those are terribly practical. Yes, you can hide in front of the sun, but the geometrical constraints on that are very difficult. Another stellar body only works if you're not running the powerplant. Exotic stellar bodies might work. I'm not sure.
"Buzzers" will have to give off the same heat signature as a ship. That requires a power plant, and/or engine of the same size. Rather expensive decoy.
Cooling is difficult, but not impossible. (Assuming that you're going to be radiating away from whoever you're hiding from. Heat sinks would reduce detection range, but due to the Newtonian environment, they're sort of useless. Everyone can see when you change course.) See the link.
As for minefields, given that Aurora is 2D, theres a much higher chance of using those correctly.
In an environtment like this, you could use mines not as denial, but delay; Knowing the systems an enemy fleet might come from, putting mines there would require them to come in more slowly and then maneuver, or jump through another system; all of this increases delay, and thus uncertainty, making attacks more risky.
Btw, excellent read!
Some top-of-the-head numbers. The circumference of Earth's orbit is approximately 9.4*10^8 kilometers. Let's assume I want to mine the whole thing, and have a 2-D ring with a 1% chance of hitting a target 100 m across. The projectiles are unguided, and I'll assume that they are stationary during passage time, as the ship velocity will be very high as compared to the orbital velocity, so there is one mine per 10 km. This works out to 94 million mines to cover Earth's orbit at 1%. If each is a kilogram, that comes to 94,000 tons, and I'd expect each one to be much, much heavier, given the magnitudes involved in Aurora.
So what about only laying mines on likely approach paths? That should bring it down to a reasonable number. Not at all. The mines will tend to orbit, which means you have to cover the whole thing. Fancy orbits might cut it 50% or more, but it's still a lot of mass. And while you could put in anti-gravity stuff, you've just removed the whole point of the exercise by adding fancy systems. Why not have something that launches missiles, like Aurora currently does? The only thing that strikes me as vaguely plausible that resembles a conventional mine is a bomb-pumped laser.
On a completely different note, there's really no point in gravitational slingshotting. You can't pick up a delta-V much more than the body's escape velocity. I'm under the impression we're operating orders of magnitude above that.
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Yes, but what was being proposed was not restricting emissions, it was using a fridge on the outside of a ship.
There is a marked difference; one requires a heat pump to reduce the temperature of the outside, and dumps all of that extra heat plus the waste from moving it, back inside.
I'd just like to point to http://www.projectrho.com/rocket/spacewardetect.php (http://www.projectrho.com/rocket/spacewardetect.php) as to why hiding/redirecting thermal singatures doesn't work.
Summary:
If you're absorbing all heat and storing it internally, you'd have to keep the exterior of your ship cooled to very low temperatures (way below freezing) to render it difficult for sensors to find you. (We could spot a submarine sized ship at 0 degrees celcius at 38.8m km away using current technology). For the ship, that would mean no sensors, no acceleration, nothing. And even then, a more advanced sensor scan would still find you, unless you're hiding behind a star or planet.
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Actually you could use a "heat sink" to hide for a short time. Say Water or Salt - you can dump energy in this stuff and you can insulate like hell fairly easely especially if you have a huge heat sink. As long your tank does not blow up you can dump energy into it. The thing is that this kind of hiding is only temporal and not 100% effective.
Actually this can double as back up energy source if you use a sterling engine or peltiers. A 11*11*11 meters storage of magnesia or the insane amount of 5000 tons stores around 1 GWH of power althought you have to invest 2 Watts for every Watt you get back out.
edit: ooops wedgebert was faster.
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Actually you could use a "heat sink" to hide for a short time. Say Water or Salt - you can dump energy in this stuff and you can insulate like hell fairly easely especially if you have a huge heat sink. As long your tank does not blow up you can dump energy into it. The thing is that this kind of hiding is only temporal and not 100% effective.
Actually this can double as back up energy source if you use a sterling engine or peltiers. A 11*11*11 meters storage of magnesia or the insane amount of 5000 tons stores around 1 GWH of power althought you have to invest 2 Watts for every Watt you get back out.
edit: ooops wedgebert was faster.
This is theoretically possible, but completely impractical. When you burn your engines, you announce your position and velocity for the world to see. From then on, I can find you whenever I want, unless you burn again. I will admit that if you could come in-system and not burn at all, it might work. But even then, I'm not sure.
As to the second, that won't work at all. You still have to get rid of the heat produced, and batteries are likely to be more efficient. Plus, I want my heatsinks empty when I pull in my radiators.
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Yush, you have 2 problems. Life support and generator waste heat, and thruster heat.
I'd like to note that the protagonist's starship in Mass Effect solves both these issues.
It uses a heat sink as Heph describes which allows temporary space to dump excess heat, at least for a time. Due to the FTL ability and thus speed of starships this means hours are needed and not weeks or months to travel to and from a target. In addition it also has a special gravity drive, allowing it to move without a thermal engine.
As for Aurora though... gravity 0% thermal drives do not exist, and if they did it would show up CLEARLY on grav sensor scans, possibly with a large equivalent tonnage increase. Heh, perhaps this should be implemented? It could be balanced in Aurora, though not quite be the stealth engine it is in Mass Effect.
In realistic Aurora, yes, stealth is unlikely... passive sensors ranges should be increased more than 10 fold, possibly 100 or 1000 fold. Note also that Aurora engines are also MUCH more efficient than conventional rockets, so more will be in thrust and less in heat, allowing higher realistic thrusts while still keeping the signatures down. Detection should not be automatic though, you still need the sensors and computation equipment and have it milspec and hardened, all of which is expensive and takes space on ships... on planets... much easier, but yeah.
My opinion is still to keep it on the same order it is right now, maybe tweak, but I doubt I'd like really realistic games with no stealth.
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The second problem in stealth is the exchaust problem. Even if you hide or mask somehow your thermals your drive has to push something out the trusters. For iondrives it could be for example xenon or lithium. This trails should be detectable althought they are rather faint.
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Correct, although it's less of a problem, and more of an insurmountable difficulty. The exhaust will be some form of plasma (at least for the drives under discussion here), which will produce a significant flare.
As a request to anyone who is interested in joining the debate on stealth, please read the atomic rockets page on detection (http://www.projectrho.com/rocket/spacewardetect.php (http://www.projectrho.com/rocket/spacewardetect.php)) before you post. It will make things easier on all of us.
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I split the stealth discussion off of the main Newtonian thread. Please use this thread for stealth discussions
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So, I read the entire page you linked, actually, I think I did in the past, so now I might have rushed a bit, I'm at work after all.
The difficulty here seems to be current Aurora systems.
In Aurora, detection is equal to being able to shoot at something; While efforts in stealth might only increase the time required for detection by a few hours, which could be helpful if you jump in at 10km/s with engines off, the main point I was trying to make is that it should be possible to mask your signature well enough that your opponent can't get a valid target lock, at least not before you.
So far, in Aurora Sensors were used not to just detect that something is there, but what is there and if it's hostile.
With a realistic sensor system, we can expect to not an ID just from Thermal emission, neither will we get a target lock or a definite Thermal output strength of the object in question, and heat seeking missiles could be easily disposed of with buzzers if they don't know the exact Thermal signature they're looking for. Well, unless it's engine thrust from a known enemy.^^
Additionally, the text deals mostly with combat situations, for example that directing thermal emissions is unlikely to work because there could be sensors everywhere.
This requires both sides to know that combat is about to take place in that system; If you jump into a new system and encounter precursors that have been sleeping there for centuries, have no engines on, no life support, no active sensors, and you got no drones deployed, they gotta be pretty much invisible to your Fire Control, and ultimately, thats all that counts.
So while I fully agree that permanent stealth is impossible in space, the questions are: What exactly is "Stealth"? And wouldn't 2 hours be enough?
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Add: One question that page obviously didn't cover properly, but we'll have to deal with in Aurora:
How do Energy Shields factor in this equation?
I suppose they give of heaps of EM radiation, but a Forcefield that can block a small railgun shot should be able to block heat as well?
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I think we are really looking at it too much from what is possible with our technology as it stands, as opposed to what might be able to happen in the setting of this game, if we can accept FTL and super-efficient power plants and so on made possible by completely made up elements, why is it such a stretch to imagine extremely powerful heat-sinks, or temperature non-conductive hulls, or shields that can hide your heat signature for a time?
I realize that that to have a sim that you can take seriously, we can't throw logic entirely out the window, but I imagine a happy medium could actually exist here without doing that.
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The made up materials are another thorn in my eye, I think we should reduce it to two or three kinds of handwavium and just abbreviate the rest, for example into "Metal", "Gas", "Rare Minerals" and "Fossil Fuels".
I suppose the correct assumption so far is that any possible Stealth is temporary, giving time to run away or attack first, but not a cloak that allows you to survey a system completely unseen for a month.
Because if we calculate with futuristic fantasy materials and possibilities, there's gotta be damn strong sensors on the other side.
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So, I read the entire page you linked, actually, I think I did in the past, so now I might have rushed a bit, I'm at work after all.
The difficulty here seems to be current Aurora systems.
In Aurora, detection is equal to being able to shoot at something; While efforts in stealth might only increase the time required for detection by a few hours, which could be helpful if you jump in at 10km/s with engines off, the main point I was trying to make is that it should be possible to mask your signature well enough that your opponent can't get a valid target lock, at least not before you.
Thank you.
However, that's not strictly true. To shoot at something, you need an active sensor lock. I do agree that more ambiguity in detection is good, but
if you're burning, there is no possibility of stealth outside of magic.
So far, in Aurora Sensors were used not to just detect that something is there, but what is there and if it's hostile.
With a realistic sensor system, we can expect to not an ID just from Thermal emission, neither will we get a target lock or a definite Thermal output strength of the object in question, and heat seeking missiles could be easily disposed of with buzzers if they don't know the exact Thermal signature they're looking for. Well, unless it's engine thrust from a known enemy.^^
Additionally, the text deals mostly with combat situations, for example that directing thermal emissions is unlikely to work because there could be sensors everywhere.
This requires both sides to know that combat is about to take place in that system; If you jump into a new system and encounter precursors that have been sleeping there for centuries, have no engines on, no life support, no active sensors, and you got no drones deployed, they gotta be pretty much invisible to your Fire Control, and ultimately, thats all that counts.
So while I fully agree that permanent stealth is impossible in space, the questions are: What exactly is "Stealth"? And wouldn't 2 hours be enough?
Why don't we expect to get an ID? We can almost certainly tell who owns it at the very least, and how much waste heat it's radiating. "Buzzers" are not going to be terribly effective unless they very closely mimic the target signature, probably on several bands. It's rather hard to fool modern missiles.
As to the last two:
1. Stealth is being able to hide from opposing sensors while accomplishing your mission. The act of being able to hide at some point is not enough in and of itself.
2. Only if your very^4 lucky.
The handwavium is the only possible mitigation, and while I'm not going to boycott the game if Steve leaves it in, I am going to argue that it shouldn't be there.
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In realistic Aurora, yes, stealth is unlikely... passive sensors ranges should be increased more than 10 fold, possibly 100 or 1000 fold.
It's not so much that sensor ranges should be increased but that the range calculation itself needs reworking.
Black body radiation (thermal sensor) ought to be decreasing by the square of the distance. And "radar" (active sensors) need to decrease by the fourth power of distance.
As for decoys, I could envision a decoy drive that masks the true delta-v of the ship.
Basically, it's a mass driver engine, not a normal drive. Your reaction mass is cooled to cosmic microwave background and fired out at relativistic velocities, and it then breaks up. If you can prevent some portions of it from heating up, then part of the delta-v obtained from the mass driver firing can't be detected and any estimates from the visible portions of the round will under estimate your delta-v.
If you fire mini-engines out the back using a mass driver (which could be as simple as a conventional solid-fuel rocket), and they begin burning immediately after exit, then any movement readings of the engines-as-reaction-mass becomes completely unreliable as an estimate of what delta-v your ship gained.
EDIT:
Following up with either some directional radiators (since your drive makes you hard to catch) or a heat sink, you can then make an approach that is incredibly hard to predict.
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The first two paragraphs are correct. The rest, not so much.
While a mass driver is theoretically much harder to detect then a plasma drive, it has several drawbacks. The first is that it requires electricity, which means that the drive efficiency is less than 25% of the thermal output of the reactor. The rest has to be dumped as heat. Why? Because reactors work best at 25% efficiency. If you want more details, go to atomic rockets. Second, the idea of putting a relativistic-velocity mass-driver on a ship is sort of problematic, as coilguns (which are basically mass drivers) are going to be quite long for even modest velocities, to say nothing of relativistic ones. Third, the pulse rate on the mass drivers will have to be quite high (tens of hertz, at a guess), and it has to be maintained as long as the engines are running. Fourth, they can still track you by the flare of your engines. All that will result is an incorrect mass estimate.
I'm not sure what the second suggestion is. Solid-fuel rocket exhaust looks almost nothing like a plasma drive, and shooting plasma drives rapidly gets expensive.
Directional radiators work against one enemy. If they're included, listening posts (or ships) scattered around the perimeter of the system should make them ineffective. The heat sink will have to be very large and very well insulated, particularly if you're using mass drivers.
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All that will result is an incorrect mass estimate.
I'm not sure what the second suggestion is. Solid-fuel rocket exhaust looks almost nothing like a plasma drive, and shooting plasma drives rapidly gets expensive.
Directional radiators work against one enemy. If they're included, listening posts (or ships) scattered around the perimeter of the system should make them ineffective. The heat sink will have to be very large and very well insulated, particularly if you're using mass drivers.
What I meant is shooting solid-fuel rockets as mass driver packets. Their movement will conceal the delta-v the mass driver engine gives to your ship.
The error in mass that the mass driver engine is meant to make is not intended to conceal your current position. Firing a mass driver is likely to generate enough waste heat that you will have to vent. However, incorrectly estimating the mass of the mass driver packet would create an error in the estimate of delta-v that your ship has gained.
This makes all future calculations of your position inaccurate. It also doesn't tell your enemies the mass of your ship.
Your reactor doesn't have to be a thermal reactor though. I imagine that such a reactor that outputs only electricity without a thermal cycle would be much more efficient. But it does not really matter if you have a small enough reactor (or running at low power). And a pretty darn huge heat sink and directional radiators.
I imagine nearly the whole ship would be dedicated to the heat suppression device.
The point about directed radiators being picked up by pickets is of course quite accurate. However, if your radiator only radiates to say 10 degrees squared, one could force enemies to picket ships all over the place in order to find you. (space is not flat, you can radiate out of the ecliptic) The other thing is that they'll have to picket the points for long periods of time (to catch anything drifting into the system under zero power) and have to regularly cycle back for maintenance and crew rest.
That said, I would think that any ship built to have a mass driver engine and dedicated most of its mass to a directional radiator is probably purpose built for something other than ship-to-ship combat.
One idea: to make a suicide run against a planet. It doesn't matter whether you even have weapons, a ship-sized object hitting the ground at high speed will likely ruin the planet as a colony destination for a long time, better still if your ship runs a nuclear reactor that then turns into an impromptu dirty bomb. If its an enemy homeworld... XD
The simple threat of suicide directional-radiating ships would force an enemy to expend humongous amounts of fuel putting ships at station points outside the ecliptic (which costs the highest amount to get to), and do that for all major colonies (potential suicide run targets). Even if all your ships get caught and destroyed, the logistics of conducting the attack is easier than preventing it. You still win.
And then if the enemies come in and blow up the pickets, your replacements won't get out there fast enough to catch any ships radiating into the hole before those ships arrive at their targets. Or perhaps no such suicide ships were sent and they just wanted the morale effect of sitting around for a couple of weeks before the sensors are replaced, wondering if a metal rock is about to drop on your head.
Of course, you still have to find crew willing to go on a one-way trip that will last months or years. But then, one can always find fanatics.
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Second, the idea of putting a relativistic-velocity mass-driver on a ship is sort of problematic, as coilguns (which are basically mass drivers) are going to be quite long for even modest velocities, to say nothing of relativistic ones. Third, the pulse rate on the mass drivers will have to be quite high (tens of hertz, at a guess), and it has to be maintained as long as the engines are running. Fourth, they can still track you by the flare of your engines. All that will result is an incorrect mass estimate.
Ok, I'll do this in detail.
1st is handled above. You can have an electricity only reactor that doesn't go through heat. (batteries? Chemical reactors?)
2nd. Have you seen the railgun values given by Steve? They shoot stuff at insanely high velocities. It's feasible to use them as a drive if you shoot 1 ton projectiles.
Maybe even 10 ton projectiles.
3rd. Your course corrections are done in bursts. Generally, you fire one projectile (better have modular ones so you can scale your thrust accordingly) to get where you're going. Or maybe you shoot a few. But you certainly don't fire off a hundred.
4th. What engines? The mass driver IS the engine.
EDIT:
Thought of something.
Could you not dump your heat into the projectile you just fired? Sure, it'll make your projectile visible, but if there's no plasma plume, they won't know the mass of the projectile.
If they don't know the mass, they don't know the momentum. Bit hard to generate an intercept now.
Scratch that, they can estimate the total heat in the projectile by observing its radiation drop over time. Can probably get a specific heat capacity (ie. material type) and mass estimate that way.
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What I meant is shooting solid-fuel rockets as mass driver packets. Their movement will conceal the delta-v the mass driver engine gives to your ship.
The error in mass that the mass driver engine is meant to make is not intended to conceal your current position. Firing a mass driver is likely to generate enough waste heat that you will have to vent. However, incorrectly estimating the mass of the mass driver packet would create an error in the estimate of delta-v that your ship has gained.
This makes all future calculations of your position inaccurate. It also doesn't tell your enemies the mass of your ship.
You still have me confused. Just what, exactly, do these solid rockets do? How do they make the enemy mis-estimate the delta-V?
I do understand one thing. I thought you were trying to conceal the mass driver within an exhaust plume, when it is the only engine.
Your reactor doesn't have to be a thermal reactor though. I imagine that such a reactor that outputs only electricity without a thermal cycle would be much more efficient. But it does not really matter if you have a small enough reactor (or running at low power). And a pretty darn huge heat sink and directional radiators.
I imagine nearly the whole ship would be dedicated to the heat suppression device.
That is true, within limits. The problem is reactor size. Even at 75% efficiency, you still have a lot of waste heat to get rid of. And leaking it out slowly is all well and good, but then your acceleration rate is pitiful to the point of absurdity.
Before we go any farther, I want one thing cleared up. Is this an Aurora solution or a real-life one? I can do either, but I need one or the other. Bits of both can make it almost work, but you'll never see that.
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In real life... you'll never get it to work.
Aurora has powerful enough mass drivers and efficient enough reactors for this sort of scheme. The problem of course is that you are getting real-life values of accelerations in an Aurora environment. Journey lengths of months aren't exactly ideal when your enemy can make circuits of his system while you drift along. (although that won't cut the number of anti-directional radiator pickets needed at all, since you can rotate a ship faster than a ship can go round. Some way of representing the ability to radiate out of the plane is needed)
--- Actually, it might be possible since Aurora has tractor beams. You can accelerate a ship to needed velocities, jump into an enemy system and detach the drive which goes back. The bomb portion of the ship does needed course corrections with the mass driver (which could end up requiring mass packets of up to half the ship's mass; NOTE: When I say "nearly the whole ship will be the thermal suppression device", I mean, the part of the ship where heat gets generated. Mass driver packets don't generate heat), then goes into full shutdown and drifts to collision with the target planet. ---
EDIT: another idea would be a spy mission where the ship drifts past a planet and reads emissions from the space traffic and such things.
Hence why I said the ships won't be used for ship-to-ship combat.
The rockets make the enemy misestimate the delta-v by concealing the amount of heat and their original mass.
Although I think perhaps the cooled projectiles idea is probably better. This one can get rid of waste heat through the rockets but will get expensive really fast. Not to mention that loading a large portion of your ship's mass with highly combustible solid fuel is not going to be a good idea.
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Come to think of it, could you not make computers run such a ship?
Computers would run the glorified missile just as effectively as people and able to do that at very much lower temperatures (especially if you have a non-nuclear power source), allowing you to save massively on the heat suppression device and thus be smaller.
Simply dumping your heat early on would let you drift while at just above cosmic microwave background. Effectively undetectable.
You can always dump your drive (with all the heat on it) once you got to your speed. And then jink a little with a mass driver to confuse prediction of the future location before essentially halting all functions.
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That said, I would think that any ship built to have a mass driver engine and dedicated most of its mass to a directional radiator is probably purpose built for something other than ship-to-ship combat.
One idea: to make a suicide run against a planet. It doesn't matter whether you even have weapons, a ship-sized object hitting the ground at high speed will likely ruin the planet as a colony destination for a long time, better still if your ship runs a nuclear reactor that then turns into an impromptu dirty bomb. If its an enemy homeworld... XD
The simple threat of suicide directional-radiating ships would force an enemy to expend humongous amounts of fuel putting ships at station points outside the ecliptic (which costs the highest amount to get to), and do that for all major colonies (potential suicide run targets). Even if all your ships get caught and destroyed, the logistics of conducting the attack is easier than preventing it. You still win.
And then if the enemies come in and blow up the pickets, your replacements won't get out there fast enough to catch any ships radiating into the hole before those ships arrive at their targets. Or perhaps no such suicide ships were sent and they just wanted the morale effect of sitting around for a couple of weeks before the sensors are replaced, wondering if a metal rock is about to drop on your head.
Of course, you still have to find crew willing to go on a one-way trip that will last months or years. But then, one can always find fanatics.
This is exactly the sort of Rube Goldbergian solution proposed by advocates of space stealth. Yes, you can, theoretically, under ideal circumstances and your set of assumptions, probably make it work. That's not the question. The question is, can it do the job better than another solution. That is the standard by which these sort of things must be judged.
First, the idea of using a ship as a weapon against a planet is just plain silly. Have you never heard of missiles? They're a lot easier to stealth as they don't have a crew that has to be kept 285K above background. (And I do know that electronics don't work well at 3K. However, a small pile of chips at, say 270K, is going to produce a lot less heat then any reasonable crew. And don't bring aliens from a supercold planet as a rebutal. That's just pleading.) They also don't require you to find fanatics, and to feed them and supply them for a couple years.
Actually, most strategic kinetic strikes are silly. Nukes work better.
Second, the entire scenario requires an open-space FTL drive that leaves no jump signature whatsoever. Wormholes, jump points, and the like are out, as those can and will be tightly picketed. The same goes for any in-system colonies of significant size. The jump in must also leave no signature. (And don't bring up Oyster Bay. Weber engineered that into the FTL system, and there was revolutionary new tech involved. It only can happen once.) These assumption can be (and have been) made, but I find them questionable at best, and pleading at worst.
Third, why do you have to send manned ships to points above and below the ecliptic? If this is Aurora, there is no ecliptic, so you can't radiate into it. If it's real life, they'll going to use robots instead. And they don't have to be fancy ones. It's an IR camera with an attitude control system and a computer. You have to know where all of them are for this to work, and they're a lot stealthier than your ship. They're also disposable.
Fourth, you're in a Red Queen's Race between multiple methods of detection. With a small reactor and a big heat sink, the acceleration is slow (particularly in Aurora terms) and it will take you literally years to get up to a reasonable speed. And by reasonable, I mean "damage comparable to asteroid impact" not "capable of Hohmann transfers". And that gives the other guy more time to spot you, through star eclipse, reflection, someone coming close, or a sensor probe wandering into the beam. With a big reactor, the acceleration is higher, but so is the detectability. The cameras just got a lot cheaper, which means I can have more.
Fifth, your math is bad. Stealth does not equal win. You haven't mentioned how it's going to get though the defenses around the target planet. Radar stealth is not a feature of this design, and assuming I'm competent and you're attacking a major planet (incompetence requires pleading, and this is entirely too expensive for a minor colony) the ship will be detected weeks out. That leaves a slow, underdefended hunk of metal at his mercy. And I doubt he'll have any.
Sixth and last, you seem to be contradicting yourself. First, you said it would cause him to miscalculate your position. This is not the same as being invisible. Yes, his math may be a few percent off, but that's not going to make him think that you're a harmless trader going in the other direction. And you've also just announced to the world that you're using a stealth drive. And that is going to bring warships with active sensors, and a very low tolerance for your presence.
What's the alternative? A fleet with missiles with nuclear warheads. Or, if you're dead set on this design, dump out passive nukes and leave. It's easier and more effective.
I apologize if I rambled on there. I rather strongly dislike this kind of thing, and decided to finish it off now. There are other problems, and I'll raise them if needed, but I hope this has settled it.
Second note, I wrote this before the previous two posts were posted. A lot of improvements were made, but not all of my points were addressed (and I'm feeling lazy) so I'll post it as-is.
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In real life... you'll never get it to work.
Aurora has powerful enough mass drivers and efficient enough reactors for this sort of scheme. The problem of course is that you are getting real-life values of accelerations in an Aurora environment. Journey lengths of months aren't exactly ideal when your enemy can make circuits of his system while you drift along. (although that won't cut the number of anti-directional radiator pickets needed at all, since you can rotate a ship faster than a ship can go round. Some way of representing the ability to radiate out of the plane is needed)
--- Actually, it might be possible since Aurora has tractor beams. You can accelerate a ship to needed velocities, jump into an enemy system and detach the drive which goes back. The bomb portion of the ship does needed course corrections with the mass driver (which could end up requiring mass packets of up to half the ship's mass; NOTE: When I say "nearly the whole ship will be the thermal suppression device", I mean, the part of the ship where heat gets generated. Mass driver packets don't generate heat), then goes into full shutdown and drifts to collision with the target planet. ---
EDIT: another idea would be a spy mission where the ship drifts past a planet and reads emissions from the space traffic and such things.
Hence why I said the ships won't be used for ship-to-ship combat.
Very good. You worked out for yourself what was wrong with your scheme.
1. Doing it, even in Aurora, produces very low accelerations. I'd estimate at the very high end, 1 km/s/day.
2. Towing something in and letting it coast (or coming out of FTL completely silent) is a lot easier, though I would prefer to do it with a civilian ship as cover.
3. Electronics are far better than humans for this.
The only thing you missed was replacing rocks with nukes.
The rockets make the enemy misestimate the delta-v by concealing the amount of heat and their original mass.
Although I think perhaps the cooled projectiles idea is probably better. This one can get rid of waste heat through the rockets but will get expensive really fast. Not to mention that loading a large portion of your ship's mass with highly combustible solid fuel is not going to be a good idea.
The rockets undo the entire system. The rocks are going out fairly cold compared to most exhaust (I do expect some heating from the mass driver) but then you light the rockets, announcing to the entire system where you are. And that you're using a drive that makes no sense at all for anyone other than someone trying to stealth a ship. Warships will come to investigate.
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That is true though. A computer run probe could do this run much better than a crewed ship.
But then, after some examination, I was approaching the conclusion that anything not a commercial ship is probably better computer run. Stealth or no.
The weight saved in life support alone already makes it alot better. Goodness knows I went to insane lengths to save another 50 tons for my ships in 5.20. And in Newtonian Aurora, mass is going to matter even more.
Although your comment about in-system transit times probably won't apply to Newtonian Aurora. You can always use normal engines to get incredibly high speeds and simply jump to your target system with whatever speed you need. I would say it could even make relativistic missiles possible. (although there is no point in Aurora since nukes are super-effective and the advantage of relativistic missiles is that you can't see where they are since you can't get the information in time. Aurora having FTL sensors kinda kills that.
Then again, you can get much higher yield per ton with relativistic rocks than nukes.
EDIT: also that kilo-ton range "missiles" do more damage than a nuke. It's like a small asteroid impact.)
Radar absorption is already present in original Aurora though. The original "cloaking device" only works on actives and makes the mounting ship appear much smaller. Which could end up (with alot of RP investment) with kiloton range ships that need an anti-missile sensor to find. (bigger resolution sensors don't even generate a contact)
-- Also to note that covering a system with anti-missile level of active sensor coverage is basically impossible
Hopefully, by the time they spot your "stealth" missile with high-res sensors on the planet, it'll be too late to try shooting it down. Especially in Newtonian Aurora where missile flight times have increased alot.
The point is to hope to conceal what your current position and velocity is so that even if they try looking, they'll have to scan large portions of the system before they can find you. They know where you *were*, but can't tell how fast you were going.
EDIT: if you were aiming at a planet, and they knew that, then they'ld have to scan a cone leading from your current position to plausible intersections with the orbit of the planet. That's too much to scan even with Aurora active sensors. At least if they need anti-missile resolution. Anti-ship resolutions can scan out to Mars orbit pretty easily.
1. Doing it, even in Aurora, produces very low accelerations. I'd estimate at the very high end, 1 km/s/day.
Nope. The 2.4GJ example railgun fires a 1ton shell with a momentum of 2 ton km/s. It also looks like a low tech railgun.
The way it looks like is that multiple small railguns would the way to go in designing a railgun-drive.
They're still better than the drives we have in RL.
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This is sure a busy thread.
So far, what I can see is that the discussion shifted from trying to hide a ship to concealing a projectiles position long enough to prevent it from being intercepted?
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Yup.
Also note to self:
When newtonian aurora comes out, I need to try "breaking" light speed. XD
Megaproject - accelerate something, anything, past light speed.
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That is true though. A computer run probe could do this run much better than a crewed ship.
But then, after some examination, I was approaching the conclusion that anything not a commercial ship is probably better computer run. Stealth or no.
We're in complete agreement on this one, though the conclusion depends a lot on how much maintainence the systems require.
Although your comment about in-system transit times probably won't apply to Newtonian Aurora. You can always use normal engines to get incredibly high speeds and simply jump to your target system with whatever speed you need. I would say it could even make relativistic missiles possible. (although there is no point in Aurora since nukes are super-effective and the advantage of relativistic missiles is that you can't see where they are since you can't get the information in time. Aurora having FTL sensors kinda kills that.
Then again, you can get much higher yield per ton with relativistic rocks than nukes.
EDIT: also that kilo-ton range "missiles" do more damage than a nuke. It's like a small asteroid impact.)
This is true, but relativistic rocks are also really expensive. After you go so fast (somewhere on the order of 2x exhaust velocity) kinetic energy starts to fall off. Unless you have antimatter drives, those aren't in the cards. The entire device was an answer in search of a solution.
Radar absorption is already present in original Aurora though. The original "cloaking device" only works on actives and makes the mounting ship appear much smaller. Which could end up (with alot of RP investment) with kiloton range ships that need an anti-missile sensor to find. (bigger resolution sensors don't even generate a contact)
-- Also to note that covering a system with anti-missile level of active sensor coverage is basically impossible
Hopefully, by the time they spot your "stealth" missile with high-res sensors on the planet, it'll be too late to try shooting it down. Especially in Newtonian Aurora where missile flight times have increased alot.
I am aware of that. However, the best cloaking devices are (IIRC) about .5%. A 10,000 ton ship would look like a 50 ton missile. However, if your opponent is of a reasonably comparable techlevel (and if he isn't, why are you doing this?) he can detect you at several hundred million kilometers if he has a reasonably-sized sensor available. And he then shoots you full of missiles. Your vessel can't take a stand-up fight, so you lose.
The point is to hope to conceal what your current position and velocity is so that even if they try looking, they'll have to scan large portions of the system before they can find you. They know where you *were*, but can't tell how fast you were going.
EDIT: if you were aiming at a planet, and they knew that, then they'ld have to scan a cone leading from your current position to plausible intersections with the orbit of the planet. That's too much to scan even with Aurora active sensors. At least if they need anti-missile resolution. Anti-ship resolutions can scan out to Mars orbit pretty easily.
That doesn't really work. If they know about where you are, and approximately how fast you're going, they will be able to find you. They know your current position just by seeing you, and Aurora ships are fast enough that they can get to your location before you can move, particularly when you're using a slow drive.
Nope. The 2.4GJ example railgun fires a 1ton shell with a momentum of 2 ton km/s. It also looks like a low tech railgun.
The way it looks like is that multiple small railguns would the way to go in designing a railgun-drive.
They're still better than the drives we have in RL.
You're confusing momentum and acceleration. My number was 1 km/s/day, which is the acceleration the ship can put on. Yours was a change in momentum. To get from yours to mine, we have to divide by the mass of the launching ship, then multiply by the number per day. Let's take a look at a ship of 10,000 tons (for a nice round number).
2 tonkm/s / 10,0000 tons = 2e-4 km/s or .2 m/s per shot.
1000 m/s/day / .2 m/s/shot = 5000 shot/day or 3.47 shot/min
2.4 GJ/shot * 5000 shot/day = 12 TJ/day or 138.9 MW.
139 MW is the power of the drive. While that's rather low, the problem is that, particularly if you're using a thermal reactor (which is pretty much a given, as all the reactors in Aurora are thermal) you have to get rid of waste heat. For a thermal reactor, 416.7 MW of it. That's a lot, and it assumes all other components are 100% efficient. Which they won't be.
You now have to get rid of all that heat. Heat sinks won't work for an significant length of time, which leaves you having to radiate quite a bit, which makes it you easy to detect.
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This is true, but relativistic rocks are also really expensive. After you go so fast (somewhere on the order of 2x exhaust velocity) kinetic energy starts to fall off. Unless you have antimatter drives, those aren't in the cards. The entire device was an answer in search of a solution.
Antimatter drives are in late game.
But then it is late game.
That doesn't really work. If they know about where you are, and approximately how fast you're going, they will be able to find you. They know your current position just by seeing you, and Aurora ships are fast enough that they can get to your location before you can move, particularly when you're using a slow drive.
They know your original velocity (say 10 kkm/s) and they know you vented weapons grade levels of heat on the order of GW at a certain point. They don't know what happened to you after that since they can't see the mass driver packets.
Which ends up with them needing to search a big cone in order to find you.
Anti-missile sensors don't cover that much area. In normal Aurora, I had a dedicated fleet scout at TL5 active sensors. It had a max range of around 180mkm. Which is about where I'd see my own cloaked design at TL4.
To get from yours to mine, we have to divide by the mass of the launching ship, then multiply by the number per day.
Here's a proposed *low tech* mass driver engine: (this looks like TL 2 or 3 to me from Steve's numbers)
2500 tons of engine for a 10 000ton ship. 25x 100 ton mass drivers firing 10 ton mass packets. Fuel takes up 5000 tons of the ship. This gives you 20 shots.
MJ per ton = 12
Total energy per salvo = 12 x 25 x 100 = 30,000
Energy efficiency = 35%
Heat dissipation = 0.6 MJ/s
Railgun surface area = 78
Heat venting per second per railgun = 46.8
Firing rate = 25 seconds
Maximum thrust time = 500 seconds
Each packet contains 1200 MJ and 4.9 x 10^3 kg km/s momentum. 500 packets contains 2.4 x 10^9 kg km/s momentum.
Final ship weight is 5000 tons. Net delta-v is 490 km /s.
So about 12x less efficient than similar tech drives.
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Is this still about normal aurora?
Given that Steve dislikes GFFP and purposefully doesn't allow player ships to perform ram actions, I don't think this would ever apply to Aurora.
And if your using Railguns to accelerate your ship, why can't you just turn them on the planet instead?
You'll even be able to get away afterwards.
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Its newtonian aurora.
The GFFP problem is the same with planetary bombardment. A relativistic ramming ship would make a planet uninhabitable in the same way as a salvo of nukes.
A big ship would survive re-entry better than a bunch of small mass driver packets. Even if they are 10 tons each.
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What does gffp stand for?
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Genocide for Fun and Profit
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They know your original velocity (say 10 kkm/s) and they know you vented weapons grade levels of heat on the order of GW at a certain point. They don't know what happened to you after that since they can't see the mass driver packets.
That makes sense in isolation, and it might even work, but only until you fire again. They have a couple of ships go to where you might be, and wait for the next shot.
Which ends up with them needing to search a big cone in order to find you.
Not as big as you'd think. They have a decent localization, and they just need to fine-tune it. Also, how do you deal with the fact that venting the heat will give away your position after you fire. You could sink it, and vent last shots heat, but that's sort of rube goldberg.
Here's a proposed *low tech* mass driver engine: (this looks like TL 2 or 3 to me from Steve's numbers)
2500 tons of engine for a 10 000ton ship. 25x 100 ton mass drivers firing 10 ton mass packets. Fuel takes up 5000 tons of the ship. This gives you 20 shots.
MJ per ton = 12
Total energy per salvo = 12 x 25 x 100 = 30,000
Energy efficiency = 35%
Heat dissipation = 0.6 MJ/s
Railgun surface area = 78
Heat venting per second per railgun = 46.8
Firing rate = 25 seconds
Maximum thrust time = 500 seconds
Each packet contains 1200 MJ and 4.9 x 10^3 kg km/s momentum. 500 packets contains 2.4 x 10^9 kg km/s momentum.
Final ship weight is 5000 tons. Net delta-v is 490 km /s.
So about 12x less efficient than similar tech drives.
Actually, even less so. That would only hold if you could fire them all at once.
4.9E3 kgkm/s / 10E3 kg = .49 km/s
4.9E3 * 500 = 2.45E6 kgkm/s
Each packet is traveling at .49 km/s, which makes the entire drive less efficient then using cold gas, which is equally stealthy. The actual delta-V available is more on the order of .34 km/s. No, that number is not an error. Your final momentum is, as you seem to have given it in kg m/s. However, I'll try that number as correct, too.
2.45E9 kgkm/s / 500 = 4.9E6 kgkm/s
4.9E6 kgkm/s / 10E3 kg = 490 km/s
In this case, the delta-V is a much more reasonable 340 km/s. However, the energy for each packet is 1200 TJ. I leave you to draw your own conclusions.
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Oh, whoops. I seem to have made a calculation error. Must have dropped 3 zeros somewhere.
Yeah, it's not feasible. The railgun isn't powerful enough. You need something on the order of 99.5% of your mass in "fuel".
What is this "cold gas" you speak of? Helium at 4 kelvin? Don't think that's going to be useful other than an attitude thruster.
We're going to need to have crew modules shed heat though (which was a suggestion I made about revamping sensors). Perhaps take the ideal temperature of the race crewing the ship and calculate a thermal signature per crew member.
And have thermal signatures drop off by the square of distance and require two things that can see it to triangulate a position.
FTL thermal sensors... who the heck knows how they work anyway?
There is another idea however, building on the idea of completely computer run ships.
Computer run ships might be able to get away with hiding their thermal signature (but not their drive signature) due to being able to tolerate very low running temperatures. Could this be used to gain a "first strike" on fixed defences / populations / infrastructure? (where fixed means anything in a predictable orbit)
Sort of like a steathy FTL-capable missile bus. Expendable too.
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What is this "cold gas" you speak of? Helium at 4 kelvin? Don't think that's going to be useful other than an attitude thruster.
No, it's generally something (helium, nitrogen, whatever) at about room temperature. It is mostly used for attitude thrusters due to low mass and simplicity, as well as low Ve. However, it is also the only system I know of that has undetectable exhaust.
We're going to need to have crew modules shed heat though (which was a suggestion I made about revamping sensors). Perhaps take the ideal temperature of the race crewing the ship and calculate a thermal signature per crew member.
And have thermal signatures drop off by the square of distance and require two things that can see it to triangulate a position.
FTL thermal sensors... who the heck knows how they work anyway?
There is another idea however, building on the idea of completely computer run ships.
Computer run ships might be able to get away with hiding their thermal signature (but not their drive signature) due to being able to tolerate very low running temperatures. Could this be used to gain a "first strike" on fixed defences / populations / infrastructure? (where fixed means anything in a predictable orbit)
Sort of like a steathy FTL-capable missile bus. Expendable too.
That's pretty much my conclusion. One caveat, though. Computers don't work that much colder than humans. They do, however, require a much smaller amount of heat, which means that they have a low, but not zero, thermal signature. (A base thermal of one should work fine. It's not completely invisible, but is is very difficult to see.)
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Can't you build circuits that use little energy? Most of the circuits can be superconducting, only the logical junctions need to have any form of resistance.
The ultimate goal of course is to run a ship at ~2.7 kelvin, which has zero thermal signature. (temperature equals CMB means you look like blank space) Although something running at around liquid helium temperatures would hard enough to spot.
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A Graphene Chip should be working at a 100 K... Sure, we can't yet make computers out of that stuff, but we're getting closer every day.
Theres also Insulations available that should be able to keep a Thermal difference of 250K for several Weeks.
What I've found, though, is that Light from a nearby star will already heat up your ship, not like an Engine, but certainly enough that you're not background anymore. We can expect there to be a star in most systems.
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The star is the problem. However, you really don't have to get to background, just enough to reduce the detection range. The best use for stealth drones is probably recon, and if you can cool it to around 100K, then it's going to be detectable at only 12% of the range of the same vessel at 290K (all numbers are approximate). Space is quite large, and scanning for stuff at 100K will take time, luck, close targets, or large targets. Also, something on an intercept course for a planet is more likely to be detected because it will appear in the same region of the sky over multiple exposures.
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A quick point about the mass driver engines. The mass of the projectile is a few orders of mangitude larger than what Steve gives in his examples. Steve talks about 400 ton rail guns that fire 2kg shells. For a 10,000 ton ship, this is going to only impart an acceleration of a few mm/sec per railgun.
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The made up materials are another thorn in my eye, I think we should reduce it to two or three kinds of handwavium and just abbreviate the rest, for example into "Metal", "Gas", "Rare Minerals" and "Fossil Fuels".
I suppose the correct assumption so far is that any possible Stealth is temporary, giving time to run away or attack first, but not a cloak that allows you to survey a system completely unseen for a month.
Because if we calculate with futuristic fantasy materials and possibilities, there's gotta be damn strong sensors on the other side.
Part of the reason for the unobtanium minerals is to encourage exploration. Otherwise, there would probably be enough of everything else in the Sol system and no need to explore. While the amount of the minerals on some Aurora planets may seem huge, a few million tons of most metals, rare minerals, fossil fuels, etc is a tiny fraction of what would be readily available in the Sol system.
Steve
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Part of the reason for the unobtanium minerals is to encourage exploration. Otherwise, there would probably be enough of everything else in the Sol system and no need to explore. While the amount of the minerals on some Aurora planets may seem huge, a few million tons of most metals, rare minerals, fossil fuels, etc is a tiny fraction of what would be readily available in the Sol system.
Steve
The solution to that is twofold:
1. There's only a very limited amount of handwavium in a given system. This forces the exploration, while removing the "I have to move how many tons between systems?" issue. A 10,000 ton ship takes 9,950 tons of metals and plastic and 50 tons of handwavium, but an average system only contains 500 tons of handwavium total.
2. Give planets a carrying capacity, and make it so that you have to explore and spread to thrive.
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I know stealth in space is probably difficult to achieve. However, a large part of the fun in Aurora (for me anyway) is that most of the time you don't know what you are up against and enemies can appear in unexpected and unwelcome locations. Detection is a very important part of the game and this is one those areas where I think fun should take precedence over realism.
Steve
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The solution to that is twofold:
1. There's only a very limited amount of handwavium in a given system. This forces the exploration, while removing the "I have to move how many tons between systems?" issue. A 10,000 ton ship takes 9,950 tons of metals and plastic and 50 tons of handwavium, but an average system only contains 500 tons of handwavium total.
2. Give planets a carrying capacity, and make it so that you have to explore and spread to thrive.
There are two issues. One is that with eleven different mineral types, you face different shortages in each game that affect different parts of shipbuilding or your economy, which may have a significant effect on strategy. The second is that if the amount of handwavium is only small, there is no significant logistical effort required to move it and logistics are both a huge part of the game and one of the reasons for creating new production hubs. Those wouldn't be necessary if you could create a few small, fast ships that brought everything back to Sol.
Steve
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I will admit that in an FTL setting like this, stealth is a lot easier. You can burn your engines well out of sight of the enemy. However, because of the much longer tactical lag (you also can't just turn around and run) some increase in detection range is probably a good thing at the very least.
I suppose you're right on the minerals thing, too. (You are by definition, but your logic makes sense too.) I'm not a fan of handwavium in general (if you didn't notice).
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While I can't really disagree with you that much, it is interesting how we came from entirely different standpoints.
I actually expected logistics to increase.
Why?
A) Every godforsaken rock in space, of a reasonable size, would be a source for one of those potential base resources. This means that even a system that otherwise comes out empty, is now worth at least something.
B) Let's be generous and assume 8 kinds of handwavium; each of them is also needed in smaller quantities, maybe about 75% of now, while the rest is done by stock materials; and is available half as often.
Now you might be in a situation where you have a large Asteroid field with tons of those stuff, but no large planet or gas giant near, so even if there was a small planetoid available and you got 7 of 8 handwavium at hand, you would need to get that stuff home somehow.
C) Stock materials would be required for the civilian industry as well, and harvesting them from inhabited planets could result in pollution, just simulated by unrest. This would mean to feed the voracious appetite of a 100 year old spacefaring Industry, one would have to place mines on a good dozen planets, and not every single one might contain rare minerals or fossil fuels in large and accessible enough quantities that it would be worth simulating in Aurora.
D) Single Example: Sorium being a bit more rare, mostly on Gas Giants, would allow players to set the mix for their standard fuel.
For a massive peacetime economy, small rations might be enough, maybe 20%; but a Warship would have 50% Sorium fuel to allow for a bit faster acceleration and higher fuel storage while retaining small size.
One could even devise Sorium Boosters that burn the valuable stuff to try and get out of the way of an incoming projectile quickly.
Additionally, you have to keep in mind that Logistics will be somewhat simplified by now having jump routes anymore.
You could complicate matters by making FTL drives cost a certain amount of special fuel, and commercial engines being not as much more effective as the ships are larger, possibly resulting in systems that are a great staging ground for attacks, but too far off to make it economical at the current tech level to ship that fuel home.
Also a possibility
You could even go as far as change the demand for various materials as times change.
EXAMPLE: Player UnLimiTeD recently finished research of Reactive Electric Armor, with a durability 20% higher than Ceramic. However, this new type of armor requires microcapacitors as part of it's structure, which require a different type of handwavium. UnLimiTeD currently does not have enough of that, and doesn't want to buy it from Steve. So he decides to keep using the old armor and order additional amounts of resources for the next Transport convoy to his mining system, hoping that by the time the stuff arrives, he'll still need it.
Theoretically, you could go as far as having those armors be more efficient against various attacks, like an extremely heat resistant ablative armor protecting against Lasers (-25% dmg) but having an overall lower strength.^^Aww, I know you won't. :P
As for stealth, I suppose as a compromise, you could give Living space a thermal signature, even if it's low.
Suggestion #2 (or was it 3?): Could you theoretically change the range calculation a bit? Instead of linear, it could be ^1.5, somewhere on the way to reality, with a higher base range, and factor in things like where the sensor is based.
A military Thermal Sensor Array on a battleship patrol would be able to find you rather easily unless you employ extensive handwavium technology, but a thermal on a Civilian ship that is not constantly monitored, while theoretically having nearly the same range against blatantly obvious threats, would be nearly bling to a small flare now and then, sneaking into position.
On Planets, Active sensors could be hindered by the gravitational field of the planet, and Passive listening posts are more efficient outside Atmosphere.
While this in total might mike stealth harder, it offers interesting decisions, where an ambush on a civilian fleet is possible when a Military fleet would possibly detect one, and covering a system in sensors will be a bit more logistically demanding. It might offer a nice amount of hide&seek where one party raids the other and disappears before the military forces come to hunt them down. As far as that is available in space.
Would a Shield generator be able to hide a thermal signature, but in turn provide an EM signature that is not scanned for on Civs, but might give Military ships a valid target ID on longer than normal ranges?^^
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Detection is a very important part of the game and this is one those areas where I think fun should take precedence over realism.
I know I go out of my way to ensure nothing escapes my sight.
I remember building a huge PDC on my homeworld that was nothing but three max-size Active Sensors (Size 1, 20, 100). At TL5, that could see basically everything in the system (the size 100 covers all jump points any time of the year)
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When people say things like "using current technology we have the ability to spot a 0o C ship from 50m kilometers away what sort of field of view are you talking about? Is this a sensor looking out over an entire hemisphere, or a 1 degree cone of sky?
Also something to keep in mind about engine efficiency is that while the more efficient the engine the less energy is released as heat, the higher the temp of the plume that is released. This may not be that important of a point though, since I am guessing that Steve will have the Thermal Sensors purely based on the power of the heat produced, and not the actual wavelengths of lights produced. (Although designing sensors that were the most sensitive at different wavelengths would be a pretty cool design metric if it wasn't overly complicated, especially since this may allow ways to pick up fighter engines. If fighter engines are less efficient that would mean that the plume was cooler (makes sense, as the plume would be smaller, so the center of the plume would be closer to the nozzle wall, meaning it would have to be cooler), meaning that if your sensor was more sensitive to the lower wavelengths you would see cooler engines (fighters) earlier than their larger ships. Another important point about that is that (As done in The Mote in God's Eye) you can guess from the temperature of the drive how efficient the engine technology is).
I also think that everyone may be a little hung up on one form of propulsion, the enormous cone of plasma thermal radiation in every direction (even in front of the ship since the plume will be bigger than the ship). Other forms of propulsion may not have the same lack of subtlety. So far the only example of an alternative drive in that of a mass driver, which could work, although it is admittedly low in acceleration. (Although I would add that in addition to the actual projectiles a Railgun would certainly emit some sort of muzzle flash, a Coil Gun may be able to avoid that). Another alternative would be a laser engine, this would take up a huge amount of power, but would only be visible in a small cone along the thrust vector (ignoring reflections off of asteroids, other ships, and even dust. In a Nebula this would be a very visible form of travel), an Ion engine is another example.
For another fairly invisible form of propulsion look no further than alpha radiation. A lower thrust fusion engine may just be able to fuse those Hydrogen atoms and toss the helium atoms out the back at relativistic speeds without the signature plasma tail, if it was being slower and more careful with it's reaction to avoid all the plasma.
Now obviously all of these methods require that the heat from your reactor be expelled in a very targeted way, because if they can see your ship then seeing your exhaust doesn't matter. However, if that can be attained you can also get stealthy movement, albeit much more slowly than a large, high-thrust rocket. I don't know exactly how Steve would model all of this stuff, would it be very hard to model ship emissions as cones (/ triangles in 2d)? The engine emission cones would always be in the direction of thrust, and maybe the thermal radiation would always be aft as well, or maybe you could optionally reorient it. (Or maybe it could just be handwaved as an engine with a smaller thermal signature)
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When people say things like "using current technology we have the ability to spot a 0o C ship from 50m kilometers away what sort of field of view are you talking about? Is this a sensor looking out over an entire hemisphere, or a 1 degree cone of sky?
Whole sky scan over a couple of days, which is plenty of time at that range.
Also something to keep in mind about engine efficiency is that while the more efficient the engine the less energy is released as heat, the higher the temp of the plume that is released. This may not be that important of a point though, since I am guessing that Steve will have the Thermal Sensors purely based on the power of the heat produced, and not the actual wavelengths of lights produced. (Although designing sensors that were the most sensitive at different wavelengths would be a pretty cool design metric if it wasn't overly complicated, especially since this may allow ways to pick up fighter engines. If fighter engines are less efficient that would mean that the plume was cooler (makes sense, as the plume would be smaller, so the center of the plume would be closer to the nozzle wall, meaning it would have to be cooler), meaning that if your sensor was more sensitive to the lower wavelengths you would see cooler engines (fighters) earlier than their larger ships. Another important point about that is that (As done in The Mote in God's Eye) you can guess from the temperature of the drive how efficient the engine technology is).
The temperature of the exhaust is inherently related to the exhaust velocity in gas/plasma engines, which is the rocket equivalent of fuel efficiency. As to actual efficiency, thermal engines (which includes most types explicitly described in Aurora) convert the heat of the gas into motion. That is going to leave a lot of heat anyway. You can't cool it enough to hide the exhaust.
I also think that everyone may be a little hung up on one form of propulsion, the enormous cone of plasma thermal radiation in every direction (even in front of the ship since the plume will be bigger than the ship). Other forms of propulsion may not have the same lack of subtlety. So far the only example of an alternative drive in that of a mass driver, which could work, although it is admittedly low in acceleration. (Although I would add that in addition to the actual projectiles a Railgun would certainly emit some sort of muzzle flash, a Coil Gun may be able to avoid that). Another alternative would be a laser engine, this would take up a huge amount of power, but would only be visible in a small cone along the thrust vector (ignoring reflections off of asteroids, other ships, and even dust. In a Nebula this would be a very visible form of travel), an Ion engine is another example.
Engines that produce plasma are pretty much the only option on the table for practical space travel. I find mass drives very iffy for any sort of reasonable propulsion, not to mention venting the waste heat. Lasers are completely impractical for onboard use. 300 MW/N is never going to be adopted by anyone in the forseeable future. And ion engines do produce plasma, if slightly colder then, say, fusion.
Edit: The ion engine exhaust should be very difficult to detect, but they have the same heat problem as mass drivers. So do lasers, for that matter.
For another fairly invisible form of propulsion look no further than alpha radiation. A lower thrust fusion engine may just be able to fuse those Hydrogen atoms and toss the helium atoms out the back at relativistic speeds without the signature plasma tail, if it was being slower and more careful with it's reaction to avoid all the plasma.
That's just impossible. You cannot have a fusion reaction without very hot plasma.
Now obviously all of these methods require that the heat from your reactor be expelled in a very targeted way, because if they can see your ship then seeing your exhaust doesn't matter. However, if that can be attained you can also get stealthy movement, albeit much more slowly than a large, high-thrust rocket. I don't know exactly how Steve would model all of this stuff, would it be very hard to model ship emissions as cones (/ triangles in 2d)? The engine emission cones would always be in the direction of thrust, and maybe the thermal radiation would always be aft as well, or maybe you could optionally reorient it. (Or maybe it could just be handwaved as an engine with a smaller thermal signature)
This requires perfect stealth and perfect detection to coexist. I dealt with this earlier in the thread, but, fundamentally, directional radiation is impractical because you have to know where all of the enemy's pickets are. And the picket can be the size of Voyager, with a decent IR camera.
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You fellows do realize that Mr. Walmsley is calling this project "Newtonian" Aurora, and not, say, "Maxwellian" Aurora. Right? His goal is to introduce some (not all!) of the basic elements of Newtonian physics with regards to movement in what is otherwise a very non-realistic setting. I have seen, over the course of this discussion of stealth, a great deal of careful thought about the present understanding of Thermodynamics as applied to what are supposed to be science fiction engines. Are we, perhaps, focusing on the wrong thing?
I have also noticed a very great deal of displeasure with the concepts of "Handwavium" and "Narrativium. " This seems very strange, as such elements are the bread and butter of any science fiction story or game. After all, if there was no fiction involved, then this would be a test engine, not a game.
If we are to discuss stealth, then let us discuss stealth as it applies to Aurora. The present system for active sensors, as I understand it, uses certain variables to adjust the effective size of a ship for the purposes of detection. Opposing this, one is allowed to adjust certain variables to adjust a given sensor platform's range to detect ships which are above a certain size. Added to this, passive sensors, with significantly greater range than active sensors, are available, with the important trade-off that they can not be used for the purpose of target acquisition. Additionally, passive sensors do not make a ship, or other platform using them, more visible to potential hostiles. Finally, all sensor information is available to all allied ships in, and out of, system in real time, at all times. Is there anything in particular that we would like to see changed, that would not massively complicate the coding of the game beyond a practical level to ask of Mr. Walmsley?
As far as I know, making sensor data Slower Than Light(STL) is generally considered to be far more trouble than Mr. Walmsley is willing to code. Making the transfer of information STL would also massively complicate administering a Multi-System Polity. So, STL information is, for the foreseeable future, off the table.
For the purpose of hiding from active sensors, at present, one can- Install a Cloaking Device to reduce a ship's apparent size for the purpose of detection.
- Actually make a ship smaller. (Insufficiently Fun. )
For the purpose of hiding from passive sensors, at present, one can- Reduce a vessel's EM signature by deactivating shields and active sensors.
- Reduce a vessel's Thermal signature by operating at less than full power.
- Reduce a vessel's Thermal signature by investing in stealthier, more expensive engines
- Reduce a vessel's Thermal signature by using fewer actual engines, capable of lower output. (Insufficiently Fun)
Do any of these options seem particularly broken or useless, given the theme of Newtonian Aurora?
For the purpose of discovering ships that do not wish to be found, one can- Increase the efficiency of sensor platforms, through research.
- Increase the size of a given sensor installation.
- Alter the size for which a particular sensor platform is optimized to search.
Are there any other methods that should be included on this list for Newtonian Aurora?
Given the new acceleration and velocity rules, and how they affect reaction times, should detection ranges be pushed upwards for active sensors? Should passive sensors get a boost? If there is a boost, should it be in the form of a linear shift to the power of sensors, either upwards or downwards? Should sensor technology improvements become exponential in nature? Or should we do something else completely, that is only now possible because of the new movement rules?
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I have a few Bad Ideas™ I'd like to throw at people regarding cloaking and detection. Has nothing to do with actual science or maths. So if you like either in your games go to your happy place. Are you there yet? No? Now? Excellent.
Bad Idea 1): Perhaps adding a time lag to detect signatures based on 1% chance per sensor per minute + Crew Experience(s) if within passive sensor strength at the target ships signature output. If the ship is outside that range then this same check is made every hour instead. Ships that are designed for/use less emissions than passives are optimised for looking for the check is make every hour again. (except for Ground Based Sensor stations in this case.)
If a ship remains both low emissions and out of range then a check is made every 4 hours.
Any ship currently successfully evading detection that changes its current emissions output (changing speed, direction, shields etc...) while in a system with ships or deep space tracking stations and not sharing sensor data through a treaty agreement has to make a new check again to see if the change gets detected. A 1% chance is small but it is based on all sensors within a solar system working together wirelessly.
Bad Idea 2): In systems with a heavy presence it is still almost impossible to get away undetected without stealth systems. Cloaking could be made to make a flat negative roll on the chance to be detected. Or better yet could cost power to produce a field that when the detection rolls say you should have been detected could cost power to make it remain negative. As well as a flat operation power cost.
This could make cloaking tech useful in short bursts such as showing up to a enemy colony. You'll be detected ages out, but you could launch a salvo gather Intel or Grav Survey a specific point. Then when hostiles are expected to get in range for a pot shot activate the cloak and make a break for it hoping it will last long enough to evade missiles or beam/munitions fire.
Bad Idea 3): Hyperspace exists in aurora. What it is or where it is, is undefined as far as I know. Therefore it could be the "handwavium" people are looking for. It already exists in the game now lets see how it could be expanded. So my brilliant bad idea is that ships with a hyperdrive could have a component added into the engines to generate a place to vent thermal radiation and unwanted materials. Heatsinks can become thermal batteries that need to be drained by venting directly into hyperspace. The downside to this could be that dedicated search sensors such as Deep Space Tracking can detect hyperspace signatures. A Hyperdump™ can be detected but the presence in system can remain unknown. Allowing ships designed from the ground up for power capacity, fuel effency and reduced emissions to perform good stealth missions but not much else since size will need to be kept to a absolute minimum.
This will allow a good sensor net a good chance to detect these cloaked pests. The down side is a lot of sensors need to be in system to catch the cloaked ships quickly. I like these ideas in general but they all still need tweaking and math values to get a good balance of stealth vs detection.
I'm going to regret this, but thoughts and opinions on the above are welcome.
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I'm going to regret this, but thoughts and opinions on the above are welcome.
You shouldn't do, if the forums keep to their same friendly aspect and people respect other rights to differing opinions
Foolish question on IR (thermal imaging) As I understand it IR cannot be used through object. Example as if your inside a dumpster then the IR signal that will be picked up is a dumpster, not the person in it, unless you are up against the side of the dumpster transferring the heat, then you would see a hot spot.
What if a spaceship had a large non conductive heat web in front of the vessel that does not conduct heat or is very minimal, with a reflective membrane on the inside to reflect the heat back. then it would hide the main heat of the ship, depend on the web you would get a aurora around the web of IR. Or would you? IR detection relies of IR waves heading towards the sensor. If those waves are not heading towards the sensor then you not pick up the IR or thermal image. It would be no different to say hiding behind an asteroid.
You may not be able to get 360 degree stealth, but you may be able to achieve 180 degree stealth.
Also with all the stars in the night sky producing IR, if you are in front of one would it blind the receiver of an object.
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A thermal shield has been discussed, but you would need to be very far out to deploy it. You must not actually have contact to it.
However, as directional stealth is hard to code with FTL Sensors, all this is impractical.
@nafaho7:
You may express contempt for the discussion, but this entire thread is about how to make stealth more realistic;
Sure, theres been a bit of discussion on how to make logistics more challenging and other stuff, a matter of believability, but I feel we have a good reason to discuss this in a potential system where a 2 ton nuke can annihilate a capital ship.
Leaving alone the economy+logistics discussion, to which I'd like, but don't expect an official response (see wall of text above), the whole discussion comes down to the following points:
A) Stealth for manned Ships is extremely hard in real space. So much for the basis.
B) Stealth in Aurora is too easy to achieve, and excruciatingly boring in that way; Emisions can not only be reduced, but eliminated.
C) The only way to reliably defend against stealth in current Aurora is absolutely humongous Active sensors, as passives become completely useless as soon as an enemy turns of his shields and stops moving.
This implies that the following changes could be useful:
A) A revamp of the range collection, lying somewhere between the current linear and the realistic sqrt range falloff. Maybe half sig=1/3 detection range or something.
A1) Possibly increase range of passives sightly, maybe only for military ships, allowing hide and seek if one raids civies.
B) Giving Crew Quarters, weapon systems, and reactors their own heat signature. While it may be small, and with the current sensor system would still allow to evade detection, it will make passives more useful as theres always a small bit of radiation. Maybe not enough for someone not actively searching, but certainly enough for an Asteroid-Based DTS.
Shields might be able to mask it, but emit stronger EM
C) Allow passives, within a fraction of their range, say, 50%, to give a target id, at a steep hit penalty, for non-homing projectiles.
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Engines that produce plasma are pretty much the only option on the table for practical space travel.
That depends on your definition of practical. A craft with .1g acceleration may not seem practical when their opponents have 3g acceleration, but for some missions it may be worthwhile. Sending a team on a three-month trajectory to destroy a poorly defended Sorium harvesting fleet can be better than sending a team on a two-day trajectory to destroy a heavily defended Sorium harvesting fleet.
That's just impossible. You cannot have a fusion reaction without very hot plasma.
The plasma has to be at the site of the fusion, it doesn't have to be anywhere else. Hydrogen is fusing right before your engine nozzle, then sure, you are spitting out a huge plume of helium spray and plasma. However if you are fusing the hydrogen in an internal reactor and using a magnetic screen to divert the flow of plasma so it remains in the reactor while the neutral helium molecules are shot out as thrust then that's completely different. You now have a stealthy engine, albeit a more complicated, lower thrust engine that has huge thermal issues since it's not expelling most of the heat that its reactions produce.
This requires perfect stealth and perfect detection to coexist. I dealt with this earlier in the thread, but, fundamentally, directional radiation is impractical because you have to know where all of the enemy's pickets are. And the picket can be the size of Voyager, with a decent IR camera.
You have to know where every single picket is to guarantee stealth. You don't need to know where any pickets are to have a better (aka non-zero) chance at stealth. Make sure that your emissions aren't pointing near any planets/moons, comets and pray. Remember that the theoretical goal of stealth is to be perfectly invisible to your enemy, but the practical goal of stealth is to buy you as much time before detection as possible.
If two months into your three month trip your emission sweeps across a picket you don't know that, but if at that point the enemy fleet around their home planets fires up their engines and heads straight at you or your target then you know that somehow you were detected, and it's time to switch to your "practical" engines. You weren't able to get all the way to your target without being detected, but your stealth systems got you a lot closer than you otherwise would have.
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You shouldn't do, if the forums keep to their same friendly aspect and people respect other rights to differing opinions
Foolish question on IR (thermal imaging) As I understand it IR cannot be used through object. Example as if your inside a dumpster then the IR signal that will be picked up is a dumpster, not the person in it, unless you are up against the side of the dumpster transferring the heat, then you would see a hot spot.
What if a spaceship had a large non conductive heat web in front of the vessel that does not conduct heat or is very minimal, with a reflective membrane on the inside to reflect the heat back. then it would hide the main heat of the ship, depend on the web you would get a aurora around the web of IR. Or would you? IR detection relies of IR waves heading towards the sensor. If those waves are not heading towards the sensor then you not pick up the IR or thermal image. It would be no different to say hiding behind an asteroid.
You may not be able to get 360 degree stealth, but you may be able to achieve 180 degree stealth.
Also with all the stars in the night sky producing IR, if you are in front of one would it blind the receiver of an object.
Some major problems with that idea:
1 - The shield will reflect some of the heat back to the spacecraft, exacerbating its original problem.
2 - 180 degree stealth is useless - the enemy only needs to have a minimum of two pickets out there in order to be able to see you.
3 - How do you make the shield accelerate at the same rate as the ship, so the two don't either collide or part company.
4 - No matter how good an insulator it is, it will still conduct some heat. Thus, it will be significantly above the cosmic background (3K).
Personally, I don't mind stealth in space if this is done for game play reasons. Though, there exist no ways of doing it in reality, which necessitates a certain quantity of hand waving.
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Foolish question on IR (thermal imaging) As I understand it IR cannot be used through object. Example as if your inside a dumpster then the IR signal that will be picked up is a dumpster, not the person in it, unless you are up against the side of the dumpster transferring the heat, then you would see a hot spot.
Over the short term, you are correct. Over the long term, you would heat up the dumpster. We just don't notice due to the enviroment being relatively close to your body's temperature already.
What if a spaceship had a large non conductive heat web in front of the vessel that does not conduct heat or is very minimal, with a reflective membrane on the inside to reflect the heat back. then it would hide the main heat of the ship, depend on the web you would get a aurora around the web of IR. Or would you? IR detection relies of IR waves heading towards the sensor. If those waves are not heading towards the sensor then you not pick up the IR or thermal image. It would be no different to say hiding behind an asteroid.
You may not be able to get 360 degree stealth, but you may be able to achieve 180 degree stealth.
That wouldn't really work. Some heat would be absorbed, which would heat up the shield. And as mentioned above, the reflected heat would compound your problems. It might help some, but also as mentioned above, 180 degree stealth isn't terribly useful.
Also with all the stars in the night sky producing IR, if you are in front of one would it blind the receiver of an object.
Actually, that's backwards. If you're in front of the star, the observer would be more likely to notice a star missing, and conclude that something was there. A star is going to have an angular size much smaller then your vessel.
That depends on your definition of practical. A craft with .1g acceleration may not seem practical when their opponents have 3g acceleration, but for some missions it may be worthwhile. Sending a team on a three-month trajectory to destroy a poorly defended Sorium harvesting fleet can be better than sending a team on a two-day trajectory to destroy a heavily defended Sorium harvesting fleet.
Reasonable thrust and specific impulse. A thermal engine can have much, much higher specific power then a non-thermal drive. And why would the two-day trajectory fleet be more defended? If you set up the vectors right, then they can't intercept you in the available time.
The plasma has to be at the site of the fusion, it doesn't have to be anywhere else. Hydrogen is fusing right before your engine nozzle, then sure, you are spitting out a huge plume of helium spray and plasma. However if you are fusing the hydrogen in an internal reactor and using a magnetic screen to divert the flow of plasma so it remains in the reactor while the neutral helium molecules are shot out as thrust then that's completely different. You now have a stealthy engine, albeit a more complicated, lower thrust engine that has huge thermal issues since it's not expelling most of the heat that its reactions produce.
Nope. The fact that it is plasma is a function of its temperature. The helium in question will also be plasma, and you will have to use several kinds of magic to neutralize it before you can spit it out. Not to mention keeping it that way.
You have to know where every single picket is to guarantee stealth. You don't need to know where any pickets are to have a better (aka non-zero) chance at stealth. Make sure that your emissions aren't pointing near any planets/moons, comets and pray. Remember that the theoretical goal of stealth is to be perfectly invisible to your enemy, but the practical goal of stealth is to buy you as much time before detection as possible.
If two months into your three month trip your emission sweeps across a picket you don't know that, but if at that point the enemy fleet around their home planets fires up their engines and heads straight at you or your target then you know that somehow you were detected, and it's time to switch to your "practical" engines. You weren't able to get all the way to your target without being detected, but your stealth systems got you a lot closer than you otherwise would have.
This assumes that lack of time before detection can enhance the performance of the mission. That is only true for extremely short timescales.
Everyone has agreed that, by nature, a stealth ship is going to suffer severe performance penalties compared to a conventional ship. I believe that detection timescales will be such that a stealth ship offers no advantages over a conventional ship. If it takes the SS three months, and the CS a month, then if the SS is detected a month out, it's no more effective, and more expensive for its combat power.
If you can avoid detection until lack of time hampers the enemy's ability to respond, then it becomes a viable method. However, I just don't see that as happening.
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Reasonable thrust and specific impulse. A thermal engine can have much, much higher specific power then a non-thermal drive. And why would the two-day trajectory fleet be more defended? If you set up the vectors right, then they can't intercept you in the available time.
The two-day trajectory is more defended because on your two-day trajectory everyone in the solar system sees you and where you are going, so the defensive fleet is waiting for you, or intercepts you. The idea that there exists a solution to "set up your vectors right" so that interception is impossible doesn't really seem to be a valid assumption.
Nope. The fact that it is plasma is a function of its temperature. The helium in question will also be plasma, and you will have to use several kinds of magic to neutralize it before you can spit it out. Not to mention keeping it that way.
I agree that there is a little bit of hand waving, but if you filter out the existing plasma and only let out the helium that have already emitted their photons to leave their excited state then they aren't going to randomly reignite into plasma once they leave the reactor.
Everyone has agreed that, by nature, a stealth ship is going to suffer severe performance penalties compared to a conventional ship. I believe that detection timescales will be such that a stealth ship offers no advantages over a conventional ship. If it takes the SS three months, and the CS a month, then if the SS is detected a month out, it's no more effective, and more expensive for its combat power.
That's not true. If the stealth ship is detected two months into it's journey then it is two thirds of the way there. It fires up its normal engine and gets there in ten days, the stealth system gave it 20 extra days to play with the Sorium harvesters and begin their escape trajectory. Sure the fact that it has a normal engine and a stealth engine may mean that its shields are halfsize, or it doesn't have as many weapons. But how many weapons do you need to destroy undefended Sorium Harvesters in twenty days?
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The two-day trajectory is more defended because on your two-day trajectory everyone in the solar system sees you and where you are going, so the defensive fleet is waiting for you, or intercepts you. The idea that there exists a solution to "set up your vectors right" so that interception is impossible doesn't really seem to be a valid assumption.
The problem is simple. The stealth ship in question has to remain undetected until it's too late for the intercept to occur. The conventional ship has to come in too fast for the intercept to occur. If the defender can have a fleet on station in 2 days, then the stealth ship must remain undetected until 2 days before it strikes. Actually less, unless you want to lose the ship. I find that sort of thing (over a long mission, no less) hard to credit.
I agree that there is a little bit of hand waving, but if you filter out the existing plasma and only let out the helium that have already emitted their photons to leave their excited state then they aren't going to randomly reignite into plasma once they leave the reactor.
The plasma will remain as plasma until after it leaves the reactor. Your problem is twofold:
1. Filter out only the parts you want to eject (magic).
2. Cool it enough to remove its signature without rendering it useless as an exhaust (even more magic).
This goes way beyond handwaving to the realm of the impossible.
That's not true. If the stealth ship is detected two months into it's journey then it is two thirds of the way there. It fires up its normal engine and gets there in ten days, the stealth system gave it 20 extra days to play with the Sorium harvesters and begin their escape trajectory. Sure the fact that it has a normal engine and a stealth engine may mean that its shields are halfsize, or it doesn't have as many weapons. But how many weapons do you need to destroy undefended Sorium Harvesters in twenty days?
I'm not sure where you're getting this from. You would get 20 extra days, assuming it takes the enemy 30 days to respond. But they will take 30 days to respond from the detection of any ship. Period. Thus, if I can get a conventional ship to the harvesters within 30 days, I can use it, too. Based on the above numbers, it takes twice as long to do something with the stealth drive as the conventional drive. What if I replace the stealth drive with more conventional drives, and use that instead?
And you keep forgetting about this thing called "escaping". That's going to be an issue for any stealth ship.
The question is not "can it be made to work under certain circumstances?" The question is "will it work better then the alternatives?"
(And my alternative involves long-range missiles. They put the ship at less risk, and don't give any response time.)
Edit:
Two more serious problems occurred to me with the example given:
1. This is Newtonian Aurora, not regular Aurora. The stealth drive will not have half the speed of the regular drive. And if you have 20 days left on stealth drive (assuming constant deceleration) then it is impossible to stop at the target within 10 days. Why? The acceleration would have to be instantaneous. Assuming the normal drive has twice the acceleration, the ship will arrive in 15 days, coasting for 5 and burning for 10.
2. You're assuming that you know when you've been detected. That's not a smart assumption. And dealing with a stealth ship that thinks you don't know it's there is easy. Launch a long-range missile salvo at it, and have it go silent for most of the run. When it gets close, it goes active, and kills the SS. And since the SS isn't using active sensors, it will probably first learn of the missiles when they come up on thermal, which is usually too close for effective defense.
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You may express contempt for the discussion, but this entire thread is about how to make stealth more realistic;
[snip] . . . the whole discussion comes down to the following points:
A) Stealth for manned Ships is extremely hard in real space. So much for the basis.
B) Stealth in Aurora is too easy to achieve, and excruciatingly boring in that way; Emisions can not only be reduced, but eliminated.
C) The only way to reliably defend against stealth in current Aurora is absolutely humongous Active sensors, as passives become completely useless as soon as an enemy turns of his shields and stops moving.
This implies that the following changes could be useful:
A) A revamp of the range collection, lying somewhere between the current linear and the realistic sqrt range falloff. Maybe half sig=1/3 detection range or something.
A1) Possibly increase range of passives sightly, maybe only for military ships, allowing hide and seek if one raids civies.
B) Giving Crew Quarters, weapon systems, and reactors their own heat signature. While it may be small, and with the current sensor system would still allow to evade detection, it will make passives more useful as theres always a small bit of radiation. Maybe not enough for someone not actively searching, but certainly enough for an Asteroid-Based DTS.
Shields might be able to mask it, but emit stronger EM
C) Allow passives, within a fraction of their range, say, 50%, to give a target id, at a steep hit penalty, for non-homing projectiles.
I have a few Bad Ideas™
[snip]
Perhaps adding a time lag to detect signatures based on 1% chance per sensor per minute + Crew Experience(s) if within passive sensor strength at the target ships signature output.
[snip]
Cloaking could be made to make a flat negative roll on the chance to be detected. Or better yet could cost power to produce a field that when the detection rolls say you should have been detected could cost power to make it remain negative. As well as a flat operation power cost.
[snip]ships with a hyperdrive could have a component added into the engines to generate a place to vent thermal radiation and unwanted materials. Heatsinks can become thermal batteries that need to be drained by venting directly into hyperspace. The downside to this could be that dedicated search sensors such as Deep Space Tracking can detect hyperspace signatures. A Hyperdump™ can be detected but the presence in system can remain unknown. Allowing ships designed from the ground up for power capacity, fuel effency and reduced emissions to perform good stealth missions but not much else since size will need to be kept to a absolute minimum.
Things like these are exactly what this thread should be focusing on. Potential alterations to the mechanics of standard Aurora to make stealth ships a possibility in a more Newtonian environment. Not details of the interaction of modern materials science on railguns with muzzle energy ratings best measured in Gigajoules. Or the precise method by which a ship may attempt to remain hidden.
Personally, I feel rather taken by options B) and C) from UnLimiTeD's post, as well as Bad Idea™ 3) from voknaar's post. For the price of yet more research, one can attempt to create stealth ships for quiet reconnaissance, or whatever other sinister purposes our wicked minds can conceive. Depending on the manner of your target's preparation and countermeasures against outside threats, these stealth ships could sometimes be a good idea, and sometimes a bad one. Like many options already in the game, a player could simply ignore it if he so chose, and use other tried and true methods of avoiding detection. A perennial favorite being the elimination of all potential sensor platforms with nuclear fire. This method generally leads to your forces being detected before it is fully implemented, but one must sometimes make short term sacrifices to aid in long term goals.
Truth be told, the best in-game method for providing sensor information on enemy star systems without producing much risk or hardship for your spacers would be some sort of cheap drone craft with whatever passive sensor technology can be crammed aboard. But it could be fun, for roleplay purposes, to have some stealth reconnaissance ships. These would be most useful in games where a player has decided to impose personal information delay rules of some kind.
EDIT: I was very recently reminded of a very good reason to build stealthy vessels in this version of Aurora. For the purposes of navigation, one is best off if the destination system has been fully surveyed. If one could deploy a stealthy survey ship, one can then more reliably plan and execute offensive operations. Such as a drive-by nuclear holocaust
instead of a direct assault by otherwise stealthy ships.
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Stealth probes are an interesting idea to drop em off have em sit idle until something flies nearby and it might give a partial report given its stealtehd nature