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Why I don't overly worry about system generation

Another reason to not worry about systemgen that much is to adjust perspective.


The game is less a real universe sim and more a scifi story sim.


I like doing hardcore that is plausible so it has a 'feel' of unique environment and consequences, but you can get that done without the current vogue of cosmology.


Another possibility is that the CT worldgen on is not crazy enough, that there will be much wider variances then we think possible from the POV of sitting on our one rock.
 
quote from previous article

But as planets decrease in mass and size, this process is altered. As smaller planets warm, their atmospheres are able to expand outward more freely due to a lower gravitational pull. As these atmospheres become larger in relation to the radius our their planet, their capability to both absorb and radiate heat is also increased. Thus, meaning the planet can more easily maintain temperature stability and stave off runaway greenhouse effects.
This means that atmosphere expansion allows low-gravity planets to maintain liquid water, even when they orbit in close proximity to their host stars.
 
coliver988 said:
But as planets decrease in mass and size, this process is altered. As smaller planets warm, their atmospheres are able to expand outward more freely due to a lower gravitational pull. As these atmospheres become larger in relation to the radius our their planet, their capability to both absorb and radiate heat is also increased. Thus, meaning the planet can more easily maintain temperature stability and stave off runaway greenhouse effects.
This means that atmosphere expansion allows low-gravity planets to maintain liquid water, even when they orbit in close proximity to their host stars.
Click to expand...

As the atmosphere expands, more is able to be driven off by solar winds, and the pressure at surface also is typically lower, thus lowering the boiling point.

On mars, even on a high pressure day, water cannot be liquid, as the pressure results in direct shift from solid to gas.

And, as it loses atmosphere to the solar wind more easily ( a higher percentage of the atmosphere is tangential and neither pushed into nor protected by the planet), the long term stability is actually reduced by the smaller world.
 
aramis said:
As the atmosphere expands, more is able to be driven off by solar winds, and the pressure at surface also is typically lower, thus lowering the boiling point.

On mars, even on a high pressure day, water cannot be liquid, as the pressure results in direct shift from solid to gas.

And, as it loses atmosphere to the solar wind more easily ( a higher percentage of the atmosphere is tangential and neither pushed into nor protected by the planet), the long term stability is actually reduced by the smaller world.
Click to expand...
I should have mentioned I was just quoting from the article: I'm a programmer, not a space scientist :)

But the gist of these things I find is that we have a very, very small sampling of the universe, and have no idea really of what is possible or not. While physics does drive a lot, what f Mars had an active core with a very strong magnetic shield that prevents solar blow-off? I think one of the ideas is that because Mars does not have that protection as Earth does, that lead to the atmosphere bleed off due to those solar winds.
 
aramis said:
As the atmosphere expands, more is able to be driven off by solar winds, and the pressure at surface also is typically lower, thus lowering the boiling point.

On mars, even on a high pressure day, water cannot be liquid, as the pressure results in direct shift from solid to gas.

And, as it loses atmosphere to the solar wind more easily ( a higher percentage of the atmosphere is tangential and neither pushed into nor protected by the planet), the long term stability is actually reduced by the smaller world.
Click to expand...

On the other hand, how long is the needed "long term stability"? NASA defines it as "long enough for life to evolve"--which is, what? millions of years, at least? The Imperium only "needs" long enough to terraform the planet, or maybe to let the Ancients do do--so an order of magnitude or three lower. A rather small planet could hold atmosphere "long enough" under those criteria.
 
Oooh--I just had a related thought! (WARNING: DANGER!)

I've noticed the many chirper and droyne worlds on the map that are small, with thin atmospheres. Maybe when they were settled (300,000 years ago or thereabouts), they had better atmospheres--dense, or at least standard, but in the intervening ages, the atmosphere drifted away, leaving them a less preferred environment.
 
BRover said:
Oooh--I just had a related thought! (WARNING: DANGER!)

I've noticed the many chirper and droyne worlds on the map that are small, with thin atmospheres. Maybe when they were settled (300,000 years ago or thereabouts), they had better atmospheres--dense, or at least standard, but in the intervening ages, the atmosphere drifted away, leaving them a less preferred environment.
Click to expand...


I'm only counting 36 Droyne worlds, but using those as a sample the median atmosphere is 6 (Standard) and the median size is 6, which gives around 5.7 molecular mass retained (by the rule of thumb) at earth density and 250 kelvins effectuve temperature. I'm presuming similar thermal lapse rates, and that effect on the scale height of the atmosphere, but I don't think 300,000 years would be enough to significantly change the atmosphere of the average Droyne world.



It was kind of a topic elsewhere too, I'm not sure if "Standard Atmosphere" means earth-like pressure (72 to 151 kPa according to MT) or earth-like O2 partial pressure with presumably limited CO2 partial pressure (~5.25 kPa) but whatever overall pressure you want within reason which might change the atmosphere evolution.
 
Werner said:
What is the jump limit for a black hole? A black hole doesn't have a radius, it only has a mass, it is a point mass in space with a certain radius calledthe event horizon, but that is arbitrary, it isn't a physical surface.
Click to expand...

There is no canonical answer that I am aware of. Most Traveller players consider the minimum safe jump distance based on planetary diameters to be an abstraction (a "navigator's approximation" with a safety margin, or "rule-of-thumb" so to speak) for a phenomenon that is really based on the local gravity gradient.

Somewhere on this forum is a nice discussion and approximation (I believe Hemdian did it a long time ago) that figured the actual "true" jump distance approximations to be based on local tidal force (i.e. proportional to Tg = GM/r3) that seemed to work very well and gave good numbers. It had an accompanying table that gave values for tidal forces at various distances, and the value at 100 diameters that figured the critical tidal force value in g's per meter.

The best part was that the tidal force method didn't give too great an amount of variation in values between stars and planets at 100 diameters (each of which obviously have different densities).

EDIT: Found it:
http://www.travellerrpg.com/CotI/Discuss/showpost.php?p=545516&postcount=13
 
aramis said:
As the atmosphere expands, more is able to be driven off by solar winds, and the pressure at surface also is typically lower, thus lowering the boiling point.

On mars, even on a high pressure day, water cannot be liquid, as the pressure results in direct shift from solid to gas.
. . . .
Click to expand...

So, on Mars, water (H2O) is Dry Ice.
 
I think he means the water is behaving as dry ice does here on earth, sublimation directily from solid to gas with no liquid phase.
 
Werner said:
What is the jump limit for a black hole? A black hole doesn't have a radius, it only has a mass, it is a point mass in space with a certain radius calledthe event horizon, but that is arbitrary, it isn't a physical surface.
Click to expand...
Not quite, the event horizon is the boundary between out universe and the strange physics that goes on inside. Also black holes have several other properties beside mass.

A black hole event horizon is therefore a radius of sorts, it is the boundary past which nothing can escape. Personally I would use the ergosphere as the radius of the black hole for jump calculation purposes.
 
kilemall said:
The game is less a real universe sim and more a scifi story sim.
Click to expand...

Quoted For Truth. Though there are players who want simulation-level quality, all of my players have been perfectly happy knowing that this is for "golden-era" science fiction gaming.
 
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