Invisibility in Space

[zozotroll]

How far out can you detect IR anyway? Sure it can go a long ways, but it has to spread out just like anything else. So by reducing your IR signature you lower the detection range.

On most any detction system you cant make yourself invisible, you just make it harder to find you, and they have to get closer. So what sort of distance are we talking here to make a reasonable chance to find you?
Owen

 

[Jeraa]

As long as you have a functional jump drive and operating power plant.

AND, you are IN jump space... Otherwise, no. There's NO rule that allows you to "switch on" a J-Drive and just leave open a hole to dump energy into. Complete fabrication on your part...

He never claimed it was a rule. As his second sentence says, it is just "One simple handwave".

 

[Jeraa]

How far out can you detect IR anyway? Sure it can go a long ways, but it has to spread out just like anything else. So by reducing your IR signature you lower the detection range.

In real life? Don't know. But in game, a starships sensors can detect thermal emissions out to distant range, which is 50,000 km and beyond. (page 144 of the core book).

 

[DFW]

How far out can you detect IR anyway? Sure it can go a long ways, but it has to spread out just like anything else. So by reducing your IR signature you lower the detection range.

Hmm, with a 1 meter TL 7 scope you could see the Space Shuttles maneuver thrusters from Earth if it was at the Asteroid belts. So, a ship with a fusion generator will end up being able to be seen from ~Pluto from Earth. VERY easy with TL 12 passive sensor tech.

 

[rust]

I think even with the best theoretically possible "thermal stealth" and with
a flight path in the shadow cone of a planet (otherwise the radiation from
the sun would heat up the hull), at the normal Traveller accelerations and
velocities a ship in interplanetary space would be detected at least seve-
ral hours before coming into combat range.

 

[Iron Warrior.]

and stealth coatings are made of snake-oil

Real world stealth coatings at least include a considerable percentage of
snake oil, just remember the stealth plane shot down by a missile over
former Yugoslavia ... :wink:

Yes, but remember that was a first generation stealth plane, we've been improving stealth tech now.

 

[atpollard]

and stealth coatings are made of snake-oil

Real world stealth coatings at least include a considerable percentage of
snake oil, just remember the stealth plane shot down by a missile over
former Yugoslavia ... :wink:

Yes, but remember that was a first generation stealth plane, we've been improving stealth tech now.

[nit pick] Technically, WW2 gliders were built for stealth as was the SR-71, so 'first generation' gets a little fuzzy. [/nit pick]

 

[atpollard]

While quite true, isn't it a little late to worry about thermodynamics?

Nope. Only toss out what MUST be. Not at a whim. Otherwise you slide quickly towards playing D&D...

I respectfully disagree. Handwaves abound. Science takes a back seat to cinema. You draw an arbitrary line.

Why doesn't the fusion reactor melt?
Where are the fragile radiators that dwarf the rest of the ship?
Whatever magic allows fusion to function, could render stealth either possible or even trivially easy.
The 'thermodynamic magic' is already there.
You arbitrarily apply a nay where I arbitrarily apply a yea.

YMMV (but so does mine).

 

[atpollard]

While quite true, isn't it a little late to worry about thermodynamics?

For example, my next Traveller starship would have a thermally super-
conductive hull coating and an advanced thermocoupling. Whenever the
ship is hit by a laser, the thermally superconductive hull coating imme-
diately transfers the heat to the thermocoupling, where is is converted
into electricity and used to power the laser which returns the fire ...

Do you mean like reflective coating for the hull that reduces damage by absorbing the laser energy and using it to keep the hull from vaporizing?
[HG describes the effect, not how it works.]
Sorry, but it looks like the standard thermocouple doesn't produce enough energy to power a laser turret ... you may need a photon drive like my hypothetical stealth ship.

My only point is that HOW tech works is ultimately Referee fiat, since the rules are game-effect oriented. So technology has consequences if YOU decide that it does, and if you decide that it doesn't, then (for some reason) that idea will not work.

 

[rust]

Do you mean like reflective coating for the hull that reduces damage by absorbing the laser energy and using it to keep the hull from vaporizing?

No, unless it is a very bad case of misnoming, reflective armour should
reflect the energy instead of absorbing it.

My only point is that HOW tech works is ultimately Referee fiat, since the rules are game-effect oriented. So technology has consequences if YOU decide that it does, and if you decide that it doesn't, then (for some reason) that idea will not work.

I see your point, but do not agree. At least my players insist on "sauce
for the goose is sauce for the gander", so once I have introduced a cer-
tain way a specific technology works, they will immediately look for the
consequences and potential other applications - the MacGyver approach.

Therefore each handwave which changes some fundamental concept of
real world science carries the risk of unintentional consequences for so-
me other part of the setting, and just telling the players that it works he-
re but not there would not be accepted by them - in their (and my) view
the main difference between fantasy and science fiction is that magic has
no rules, while science and technology have rules.

 

[DFW]

I see your point, but do not agree. At least my players insist on "sauce for the goose is sauce for the gander",

Same with my players. They tend to be science educated and will pounce if they see something like no 2nd Law. They will then apply the rules of the game "world" universally. I could get a way with this type of thing when I was teaching kids to play Trav but, I can't with the adults I game with.

 

[SSWarlock]

For example, my next Traveller starship would have a thermally super-
conductive hull coating and an advanced thermocoupling. Whenever the
ship is hit by a laser, the thermally superconductive hull coating imme-
diately transfers the heat to the thermocoupling, where is is converted
into electricity and used to power the laser which returns the fire ...

Also known as a black globe..or white globe at a higher TL in MegaTraveller.

 

[CosmicGamer]

My only point is that HOW tech works is ultimately Referee fiat, since the rules are game-effect oriented. So technology has consequences if YOU decide that it does, and if you decide that it doesn't, then (for some reason) that idea will not work.

As I always say, the details of how future tech works should be unknown, mostly unexplainable, and almost magical us the players. If we knew how it works it would be current day tech and not future tech.

Therefore each handwave which changes some fundamental concept of real world science carries the risk of unintentional consequences for some other part of the setting

Why does a "handwave" have to change fundamental concept of real world science?

I constantly use a "handwave" to explain everyday things to my young grandchildren. The details of the science is oft beyond my ability to explain let alone the kids ability to comprehend.
Child Q: "How does a microwave oven work?"
My A: "Just like the oven. It uses electricity to heat the food."

Brought up in numerous discussions, and here it is again; Traveller has Jump drives and anitgrav so adding in more tech that is "handwaved" is fine to me.

 

[atpollard]

I see your point, but do not agree. At least my players insist on "sauce for the goose is sauce for the gander",

Same with my players. They tend to be science educated and will pounce if they see something like no 2nd Law. They will then apply the rules of the game "world" universally. I could get a way with this type of thing when I was teaching kids to play Trav but, I can't with the adults I game with.

So no fusion in YTU?
(what contains sun-like temperatures without melting or creating an unmanagable heat load for the hull area to radiate?)
The 2nd Law of Thermodynamics is already in trouble that I had nothing to do with.

I am not against hard science.
I just see so many existing violations in the name of playability and fun that I find it hard to worry about one more handwave.

Reconciling the stated detection range with hard science will require something to give somewhere.

 

[rust]

I constantly use a "handwave" to explain everyday things to my young grandchildren.

I do not play with young children, the players do not stop asking when I
give them a meaningless pseudo-answer. They play the roles of engi-
neers and scientists, and would not feel comfortable if all their charac-
ters understood of their professions would be "it works with electricity".

Brought up in numerous discussions, and here it is again; Traveller has Jump drives and anitgrav so adding in more tech that is "handwaved" is fine to me.

Not to me, in fact we have already deleted both the jump drive and the
gravitics from our settings.

 

[atpollard]

Do you mean like reflective coating for the hull that reduces damage by absorbing the laser energy and using it to keep the hull from vaporizing?

No, unless it is a very bad case of misnoming, reflective armour should
reflect the energy instead of absorbing it.

Reflect microwave, visible and IR wavelengths?

EM band physics isn't my expertise, but I think that violates some law of science, so either way ... you got trouble.

 

[rust]

EM band physics isn't my expertise, but I think that violates some law of science, so either way ... you got trouble.

Traveller got the trouble, not me. :lol:

We do not use reflective armour in our settings, it is among the many
questionable or outdated Traveller technologies we decided to delete
or to replace with technologies from the real world or from other ga-
mes which are at least somewhat more plausible.

This does of course not mean that we play entirely "hard" science fic-
tion, as this would probably cease to be a game that makes fun, only
that we do not use those elements where we suspect a contradiction
with established laws of nature.

 

[DFW]

So no fusion in YTU?
(what contains sun-like temperatures without melting or creating an unmanagable heat load for the hull area to radiate?)
The 2nd Law of Thermodynamics is already in trouble that I had nothing to do with.

No, nothing that isn't REQUIRED for the game world (Jump, power source, interplanetary travel). I don't know how many times I can say it before you understand...

 

[DFW]

Reflect microwave, visible and IR wavelengths?

EM band physics isn't my expertise, but I think that violates some law of science, so either way ... you got trouble.

Not at ALL. But, that's why we have a different take on it. Different levels of understanding. There are areas of biology that I don't understand and my game rules might rub someone like rust the wrong way because of it...

But, as GM it is your game and you must satisfy your players for fun to occur.

So, no right or wrong, just what works for you.

 

[far-trader]

There are areas of biology that I don't understand and my game rules might rub someone like rust the wrong way because of it...

But, as GM it is your game and you must satisfy your players for fun to occur.

So, no right or wrong, just what works for you.

I love this clarification DFW. Too often my complaint with experts when playing this game is they can't stand to see their area of expertise riddled with flaws (vis-a-vis reality) for the sake of game play but take equally huge exception when experts of other areas point out the flaws therein that rob them of their fun in that area of game play.

In short: It is a game.