Gas Giant system building

[Malenfant]

Vaguely related to the Regina thread...

Someone on rpgnet made the mistake of asking for an astrogeologist to help him design a system with a habitable world around a gas giant on an eccentric orbit around a star...

http://forum.rpg.net/showthread.php?t=196350

I chip in with the realism on page 4, and it all goes downhill from there

. Anyone interested in reading about how such a system would work (or not, as the case may be) might like to check it out though. I think I've persuaded him it'd be easier to go for a tidelocked world like Aurore from 2300AD though...

 

[LordVince]

Y'know, Mal, given that so many worlds in Traveller (or was it MT?) seem to be satellites of Gas Giants, I wonder if it wouldn't be worthwhile to put together a kind of "World Creation Rules Subset" for Mainworlds that orbit Gas Giants.

I mean, after all the discussion about Regina -- and over on rpgnet -- it seems pretty obvious that there are some flaws in the current system...

 

[Ran Targas]

Any reason why we need to force Earth-like planets to exist? I know CT/MT assumes there are a lot of Terra/Norms out there, but I thought the majority of these were excused away as Ancient science projects.

IIRC, Earth is Earth-like due largely to the life on it. It could have turned out very different from the very start given different or an absense of life. Trees, algea, and seaweed sustain much of the O2 levels, remove large portions of C02, and reduce the effects of differential warming. Animals and insects add CO2 in massive quantities, creating zones of differential warming, and reduce O2 content in the atmosphere (not sure the gross effect compared to fires, oxidation of exposed metals, etc. but I'm sure the biomass does have a measurable effect).

My point: to have an Earth-like world, you need an self-sustained (or nearly so) Earth-like ecosystem. Otherwise, the ecosystem will produce something other than Earth-like conditions. So to create a human habitable moon orbiting a gas giant in an elliptical orbit around its primary, you would have to adapt an terran-like ecosystem. Otherwise, it's hard shelters, vacc suits, and airlocks.

IMTU, most human habitats are artificial (domes, agros, etc.) or the result of terraforming near twins. Those capable of supporting Earth-like life are engineered to due so (and so are the creatures) and are normally kept pristine (i.e. no industry, small populations, recycling of waste, etc.) These worlds are culturally, economically, and militarily significant because they are extremely rare and represent a large portion of the food grown to support the rest of humanity. Often these worlds represent the power behind an aristocrat, as with out them, a subsector could go hungry.

Anyway, my .02 credits ...

 

[Fritz_Brown]

Well, Ran, though terraforming might help with a lot of things, it won't help much with things like tide-locked worlds. But, I'll get down off the soapbox and let the guy up here who can explain it much better than I. Mal?....

 

[Malenfant]

Well, they're only excused as 'Ancient science projects' because the world generation keeps making worlds and systems that can't work in reality without some massive magic armwavy intervention.

As I've said before, the problem with Trav is that it turns the extraordinary into the norm, the exceptions into the rule. And the universe doesn't work like that. No consistent universe should work like that either, because if you're going to have all these wacky things that can't technically exist and that require all sorts of justifications to make them possible, then you may as well just stop pretending you have any consistent rules or order in the first place.


Though looking at it, it really doesn't look like gas giants are places that would be likely to have habitable moons. The best place for life really does seem to be an earthlike, non-tidelocked planet in its own orbit around the sun (like our own).

 

[Flynn]

On May 30, National Geographic Channel broadcast a two-hour TV special entitled "Extraterrestrial", which looked at the possibilities of life on distant worlds. One of them was a habitable moon orbiting a gas giant, IIRC. Don't know much about the scientific validity of their assumptions, but it was presented in such a way that it appeared to be scientificly sound.

http://www.space.com/entertainment/050527_review_extraterrestrial.html

Hope this helps,
Flynn

 

[Ran Targas]

I taped that and haven't had the opportunity to watch the whole thing yet. There again, between "Extraterrestrial" and "Alien Planet" you have three worlds that, although full of life, would be very hostile to humans.

Humans exposed to oxygen levels as high as those depicted on the one world in "Extraterrestrial" would die horribly of oxygen poisoning. And who knows what kind of nastiness get expelled from the gizzards of those animals ...

Ever read 2067? The big Europan ocean predator eats the body of the one astronaut, only to succomb immediately to convulsive vomiting due incompatible biologies. What about that Trek episode with the alkaline vegetation (you know, the hippy episode?); it killed that dude with the scallop ears as soon as he ate some. In Trav, this (or worse) should be the norm NOT a bunch of M-Class planets were everyone jumps out of the Sulie in shortsleeves and plants a flag for crown and Imperium.

Like I said, MTU is not so friendly to vacationers. There are so few Terra-norm worlds that people fight wars over them and the basic components neccessary to support life are an economy unto itself.

 

[Malenfant]

I think that Ran's got a point there - there's a zillion things that could render what looks like a 'habitable world' uninhabitable to humans without filters or spacesuits (compatible bacteria and disease that would need to be dealt with being one of the major problems).

As time goes on I am growing more and more convinced that Earth is the only human-compatible, habitable world for several thousand lightyears in any direction...

 

[LordVince]

As long as this thread has diverged from Gas Giats to Terran-Type worlds...

Now, I know that there have been endless discussions over the Pros and Cons of the UWP system, but I have always felt that there was a Digit Missing -- Biosphere.

Population, Government, and Law Level are all about INTELLIGENT life on a planet. T20 sorta delt with general bio-diversity with "Step 7 - Indigenous Lifeforms", but doesn't assign it a UWP Digit.

I've always thought thatthe UWP should read Size, Atmosphere, Hydrosphere, and BIOSPHERE.

Biosphere would, of course, be influenced by Atmosphere and Hydrosphere

The list could run from Sterile (X, or maybe 0), to Limited Environment (i.e., Ocean-based only, or Land-based only, or even Airborne only), to Full-Range -- and, with the number of options that the Hexidecimal system gives, these could be further defined as "Human-friendly" or not (or whatever the proper Biological term is for "won't kill Humans on contact"), or some kind of "Complexity" Index (i.e., is it a world of jungle, plains, desert, and oceanic life, or is it a world covered in nothing but a variety of mosses?).

 

[mike wightman]

In the game Imperium, set in the OTU past, worlds could be terrraformed in one hundred years.
Terraforming is also mentioned in CT Supplement 3.
I don't think that it's just the Ancients who are responsible for all the habitable worlds in the OTU, I think a lot have been modified by the various Imperiums.
I also think that DGP goofed when they put terraforming so high up their expanded TL chart.
It should be TL dependent based on the type of world that you are trying to engineer.

Near Earth like worlds could be terraformable at a lower TL than tidal-locked moons of gas giants etc.

 

[LordVince]

Now, see, THAT could even be a code for a Biosphere UWP Digit -- Terraformed (or Modified Biosphere, for non-Terran types)!

And I agree with you Sigg, the closer a Planet is to the "norm" that you want to get it to, the quicker/easier a Terraforming project would be -- if you want to turn a Mars-type world into an environment like San Francisco, it will take longer, and be more complicated (higher Tech), than if you're just trying to make the world like the Ghobi Desert.

 

[Ran Targas]

Originally posted by Malenfant:
I think that Ran's got a point there

Whoa! Mal agrees with me? I'm saving this one!

 

[kurtis]

Originally posted by Ran Targas:
Like I said, MTU is not so friendly to vacationers. There are so few Terra-norm worlds that people fight wars over them and the basic components neccessary to support life are an economy unto itself.

You are officially my Hero of the Week(TM)!

 

[Ran Targas]

Originally posted by Silent Cartographer:
You are officially my Hero of the Week(TM)!

Hmmm, not sure just how to take that but thanks anyway!

 

[kurtis]

Just another silly way to say "me too".

We all have our own 'IMTU' agendas, and sometimes its nice to see someone else perfectly express a shared opinion better than you could.

 

[Ran Targas]

^ Okay then, I gratefully accept the temporary position of Hero.

Back to the point; I like the ideal of exploring a tidally locked moon of a gas giant, orbiting eccectrically around its primary. It brings a lot of interesting images to mind and would truly be a unique gaming experience. But, IMHO, finding life (in any proximity to life as we know it) there would be very unlikely.

Perhaps we need a new kind of lifeform to fill this void; maybe something plasmatic or crystalline or dark matter/zero energy based? Or maybe something left over from when a First One attempted to reform the environment to suit their needs, hmmm? Now that could be truly horrific!

 

[Psion]

Originally posted by Ran Targas:
Ever read 2067? The big Europan ocean predator eats the body of the one astronaut, only to succomb immediately to convulsive vomiting due incompatible biologies. What about that Trek episode with the alkaline vegetation (you know, the hippy episode?); it killed that dude with the scallop ears as soon as he ate some. In Trav, this (or worse) should be the norm NOT a bunch of M-Class planets were everyone jumps out of the Sulie in shortsleeves and plants a flag for crown and Imperium.

Like I said, MTU is not so friendly to vacationers. There are so few Terra-norm worlds that people fight wars over them and the basic components neccessary to support life are an economy unto itself.

FWIW, I remember some references (MT Vilani & Varger I think, possibly elsewhere) that humans on Vland had much more restricted diet options and had to prepare some food in special way owing to their non-compatible biology.

However, the issue of so many habitable world in the OTU sort of buggers with me. I had assumed IMTU a Niven-esque solution of assuming the ancients seeded dozens of worlds with some kudzu-like lower life form that would help bring about an O2 atmosphere and establish a baseline for more consistent biology. Of course even ancients time scale is recent in geological terms, so it may have been ancient-ancients.

While on the topic, how buggered is the freelance traveller article on the topic? I had been assuming it was not that far off:
http://www.freelancetraveller.com/features/science/gasgiants.html

 

[far-trader]

Yep, my take on the seemingly compatible biospheres throughout Traveller's charted space (and beyond) is due to the Ancients terraforming the worlds they seeded. Not all these worlds took and some reverted back to alien biologies or drifted there. The worlds seeded with Human stock were the most successful (Terra, Vland, Zhodane, and many minor worlds). Others, like the Aslan, had many more local extinctions due to their nature, while some were unintended consequences. Shhh, don't tell the Vargr They were the transplanted canines of the humans in that area. The humans died and the canine stock thrived and evolved. And other such nonsense imtu.

 

[mike wightman]

You don't have to look as far back as the Ancients.

If the Imperium boardgame is a true history of the OTU then both the First Imperium and the Terrans could terraform worlds in only one hundred years.

I suppose interpretations could vary over what this represents.

It could be the seeding of almost Earth-like biospheres with genetically engineered microbes that make the native fauna and flora more compatible - or extinct ready for replacement;
or it could be the construction of environmentally sealed arcologies from which the population could then expand as the need arrises;
the warming of Mars-like worlds, or crashing comets into Venus-like ones.

Terraforming of planets is mentioned in the CT Spinward Marches supplement, so the Third Imperium could still do it too
The good folks at DGP chose to include terraforming too far up their expanded tech tree IMHO.

 

[far-trader]

Hmm, which book was it that expanded on terraforming, with different TL's and ability to change the envirionment dependant on starting conditions and listing how long each step would take?