And going against everything Project Rho and their excellent compilation on sci-fi tech, with far more physics than I could understand, says about stealth in space. http://www.projectrho.com/public_html/rocket/spacewardetect.php
That is, they infamously drone, “There is no stealth in space.” And then they laugh at you for trying the alternatives. And here is where I think they are thinking too much like a physicist who assumes information equals certainty. Not enough as a tactician who has to interpret the data, the poor snob reading the scope, and let alone the politician who has to decide whether or not to go to war based on those blips that he may or may not see on the screen.
First of all, I am going to agree with this article against Rho: http://scienceblogs.com/builtonfacts/2010/03/10/while-doing-some-poking-around/ and say “Internal Heat is irrelevant.” Now, that is not the case to the crew who has to deal with said heat–like the Normandy in Mass Effect. You’d need massive heat sinks to bury your signature for even an hour. But the potato is a viable analogy. Internal heat does not mean the skin is hotter. And as long as the skin remains essentially dead space, you aren’t detected. So if you train your bloom away from the detection apparatus of the enemy, and then ensure you don’t heat the skin, you should be clear from anything but luck.
Second, we can scan the entire night-sky in four hours. But anything outside your star system is essentially irrelevant. By the time you could intercept, they would jump away, and your fleet is going the wrong direction. Battles would naturally occur near fortified or strategic targets, or on the trade routes between them. Anything else, and space is so big, awareness of existence is pointless.
Third, if it’s so easy to detect everything in the night sky, why do so many asteroids go by at bullet burn range? After all, the sunward side of these is heated well above background. They should be seen for weeks, if not months, before they slip past Earth. Instead we hear of events like this: http://www.thedailysheeple.com/undetected-asteroid-explodes-over-the-atlantic_012014 on essentially an annual basis. So again, if you know where the enemy is observing from, and you orient your ship so your trail is aft of the other guy’s heat sensors, there should be functionally a low enough signature to make it unclear if you’re a ship, or just another piece of space junk.
And this is where I have my beef with Rho. Stealth as we know it isn’t ‘invisibility.’ Even a submarine doesn’t operate on absolute non-existence, or you get detected for being an impossible hole in the ocean. (I can neither confirm nor deny personal knowledge of such phenomenon.) Stealth is about the creation of doubt. The ability to convince the guy at a radar board that he’s looking at a bird instead of a plane. That the submarine is a whale, or a school of fish. Just the same, if you can make your Super Star Destroyer look like a freighter, even if your enemy knows SOMETHING is there, they may not know the Galactic Empire is on their doorstep and bombardment is ready to begin until they disintegrate your orbital defenses. Would it give them enough time even to refer that portrait in the sky to his High Command? Perhaps enough to make your President jittery about lighting off your orbital defenses?
Also there’s the issue of the difference between detection and targeting. You know an enemy is there even perhaps. But between passive stealth, active jamming, and decoys, can you be sure of what you’re shooting at? Can you be as sure as the guy who only has to shoot at one ship, which he’s positively identified and has a firm tactical solution on?
I agree that the Cloaking Device, and such gimmicks for ‘absolute’ invisibility would be impossible. But this is not the same as “Stealth is irrelevant.” This is like saying that because jamming doesn’t stop every missile, it isn’t useful, even if it stops 90% of them. It’s sure a whole lot easier to shoot down 1 missile with your point defense than 10.
So there’s still room to wish confusion to the enemy. IMHO.