Newtonian Stealth

[bean (OP)]

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.

[UnLimiTeD]

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!

[Elouda]

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.

[Panopticon]

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.

[Elouda]

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.

[bean (OP)]

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.

[wedgebert]

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 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.

[Mel Vixen]

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.

[bean (OP)]

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.

[Antagonist]

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.

[Mel Vixen]

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.

[bean (OP)]

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) before you post.  It will make things easier on all of us.

[Erik L]

I split the stealth discussion off of the main Newtonian thread. Please use this thread for stealth discussions

[UnLimiTeD]

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?

[UnLimiTeD]

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?