MarcusIII
Emperor Mongoose
Won't work. See thermodynamics for more details.
Space Combat - Did I miss something?
- Thread starter Galen
- Start date
Condottiere
Emperor Mongoose
It's an option that the Traveller provides.
I'm rather fond of going the dump heat through the jump drive route.
I'm rather fond of going the dump heat through the jump drive route.
MarcusIII
Emperor Mongoose
Yes, it's magic
Ultimately the problem with "thermal automatically detects every object in the system" is that you have trillions of faint signals and little data about distance.
You can use spectrographic analysis to exclude stars, and sizable bodies aren't difficult, especially if you already know where they're meant to be (which for civilized systems will be the case). And objects maneuvering will be detected as such and are likely ships. Asteroids don't change course much (And note that that DEFINETLY includes thrust to and from midpoint). As soon as you USE that stealth M-Drive you immediately show up as a likely ship, unless somehow the hull is a black body as well.
But a cold ship is going to be hard to distinguish from a small asteroid unless you can get an active ping on it, and once we're looking at significant numbers of light minutes, any reflected signal may not be strong enough for a ship's sensors to give you more than range. As I already bought up, active sensors WILL give you confidence that the signal is "out of range", but the margin of error on HOW far out of range may be quite high. Even so, "Captain, I have a probable ship signal on bearing 018 by 065, somewhere between the orbit of Mars and Jupiter" IS useful information.
You can use spectrographic analysis to exclude stars, and sizable bodies aren't difficult, especially if you already know where they're meant to be (which for civilized systems will be the case). And objects maneuvering will be detected as such and are likely ships. Asteroids don't change course much (And note that that DEFINETLY includes thrust to and from midpoint). As soon as you USE that stealth M-Drive you immediately show up as a likely ship, unless somehow the hull is a black body as well.
But a cold ship is going to be hard to distinguish from a small asteroid unless you can get an active ping on it, and once we're looking at significant numbers of light minutes, any reflected signal may not be strong enough for a ship's sensors to give you more than range. As I already bought up, active sensors WILL give you confidence that the signal is "out of range", but the margin of error on HOW far out of range may be quite high. Even so, "Captain, I have a probable ship signal on bearing 018 by 065, somewhere between the orbit of Mars and Jupiter" IS useful information.
MarcusIII
Emperor Mongoose
With magic. They wrote a rule saying so.
Sigtrygg
Emperor Mongoose
No you don't.
You have objects radiating reflected solar energy, and you have fusion reactors heating spacecraft to several hundred degrees above background.
This is the bit that is wrong. The ship has a multi-gigawatt fusion reactor and has to radiate a lot of waste heat. Asteroids don't. If you want to turn off your power plant, zip up in Vacc suits and run with a cabin temperature of almost absolute zero good luck. You are blind and at the mercy of your vector. Also asteroids etc follow orbits, orbits are very slow compared with Traveller ships.
And you have given away your position by going active.
MarcusIII
Emperor Mongoose
Everyone should read the part on atomic rockets about this. All the arguments that get shot down are on there too so one doesn't have to waste their time getting shot down again.
Uh, maybe I wasn't clear. That's exactly what I meant by a "cold ship". Maybe a derelict.
You're right that thermal can likely detect ships that are running silent. But the issue remains about range being nebulous.
EVERYTHING follows orbits. I get what you're saying; but velocity is another thing you're guessing at without range data. Is it a close by object moving (relatively) slow, or a far away object moving (relatively) fast? But if it maneuvers, that does give you some more data, especially if you can constrain its thust to likely parameters.
Condottiere
Emperor Mongoose
How hot does fusion plus get?
Maybe, should customize it to fusion minus for a lowered temperature.
Maybe, should customize it to fusion minus for a lowered temperature.
How much peanut butter is in your chocolate?
It is arguing about the real world effects of space magic.
IMHO, the correct approach is to decide what the end result you want is and then invent space magic that produces that end state. Do we want space submarine warfare? Then "space magic heat sinks" exist and work like this, while ultratech post digital virtual array sensors work like that. And this combines to mean "the thing we wanted works how we want!"
MarcusIII
Emperor Mongoose
Space is about -450 F. Room temp is +71 F. So even if your ship is running at room temp you are still a bonfire against the background of almost absolute zero space for IR sensors.
Sigtrygg
Emperor Mongoose
Doesn't matter how hot it gets, everything in the ship that uses electricity produces waste heat. It is simple conservation of energy and basic physics.
Your fusion+ generator may hum along at room temperature, but is producing several gigawatts of electricity, that is all going to become waste heat.
The maneuver drive doesn't use enough energy to achieve the momentum change (acceleration/work) it produces for the ship, so there is a mechanism we don't understand and hasn't been explained - space magic.
Sigtrygg
Emperor Mongoose
Which gives me another opportunity to say they can have my gravitic heat exchange mechanism for free, using a gravitic heat sink gives you a mechanism for dumping energy outside the ship.
Condottiere
Emperor Mongoose
There seems to be two issues in contention:
1. Waste heat disposal
2. Non detection of excess heat.
For the stealth stuff, you'll just have to design spacecraft that take advantage of all the MacGuffins the game provides.
For waste heat disposal, either don't accelerate, or, transfer the heat to something else.
1. Waste heat disposal
2. Non detection of excess heat.
For the stealth stuff, you'll just have to design spacecraft that take advantage of all the MacGuffins the game provides.
For waste heat disposal, either don't accelerate, or, transfer the heat to something else.
The sun side of near earth asteroids is typically about 25-30 C. Considerably above room temperature.
Presumably that's going to be about the same for most other objects in the hab zone of most stars.
Oh... and that reminds me of another thing. Your thermal sensors are mostly detecting the AMOUNT of heat radiated, which is a function of surface area. A ship radiating a certain value of heat may be hard to distinguish from an object radiating less heat per square metre, but with more square metres of facing surface area. (Emphasis on the "may be". Spectral analysis of reflected light would often be enough to say "ship or rock"... and honestly, in almost all cases a ship is going to be detectable as a ship for a bunch of other reasons, from transponders through maneuvering and using its own active sensors)
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CordwainerFish
Emperor Mongoose
Stars also tend to be in the same place as they were last week.
