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Old 08-24-2019, 12:56 AM   #1
scc
 
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Default [Space] Worlds Types And The Species That Live On Them

OK, in my last thread I talked about tentative plans I have to run a game on a Starfire scenario, specifically one based upon the fall of an evil empire due to civil war, the setting is the (power) vacuum that follows, where no governments reach is greater then the planet it's based on and there's no international/interplanetary community.

As a part of this I wiped up a table for Space world types and sizes based upon the one used in Starfire to better visualize them and figure out what sort of species could/would live on them without it being a hostile environment and it's actually rather interesting:
1. There's no Hadean world type for Tiny or Large worlds for some reason.
2. There's no Rock world type for Standard or Large worlds for some reason.
3. The Chthonian world type is an anomaly as Standard and Large, by definition, have strong enough gravity to maintain an atmosphere despite factors like solar wind, yet these worlds lack atmosphere's because of the action of solar wind.
4. The switch to Ice type worlds occurs earlier for Standard and Large Worlds then it does for Small and Tiny ones, it's rather weird.

Now I'm only concerned with worlds that humanity could invade as it's rather hard to enslave the people of a world if you can't send in the stormtroopers, and it's also rather hard to have the PC's have interactions with races that live in such environments. For each type of life Homochirality will apply, and gravity factors for Water-Based life, as high-grav worlds are not nice places to live, so the simple parts is:

Water based life [4 Species] for Garden Worlds (Standard and Large)
Methane based life (Anaerobic) [4 Species] for Ocean Worlds (Standard and Large)
Sulfur based life [2 Species] for Sulfur Worlds
Ammonia based life [2 Species] for Ammonia Worlds

But that's the simple stuff. A species that evolves on on a Chthonian world is presumably Silicon/Liquid Rock Life and it could live on worlds similarly close to a star, like say Mercury. But could such a race live on the Moon or Mars without life support gear, and if not what type(s) can? Any help is appreciated.

Final Note: The questions this raises highlighted a problem, if only a small one, with how worlds are classified in Space, the classifications are not very helpful in telling you what type of life might live on a world, nor does it touch on the issue of if these other types of life exist how might they change their world, like how the presence of life on Earth changed it from an Ocean World to a Garden one.
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Old 08-24-2019, 06:42 AM   #2
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Default Re: [Space]Worlds Types And The Species That Live On Them

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Originally Posted by scc View Post
1. There's no Hadean world type for Tiny or Large worlds for some reason.
Hadean and ice worlds have an interesting relationship. The main difference is that ice worlds have an atmosphere, while Hadean worlds do not. The exception to this is tiny (ice), which doesn't have an atmosphere, and I like to call tiny (Hadean). Once you make this switch, the reason for Large not having Hadean and tiny not having ice is more apparent: tiny planets are never big enough for atmosphere, and large planets always are.
Quote:
2. There's no Rock world type for Standard or Large worlds for some reason.
3. The Chthonian world type is an anomaly as Standard and Large, by definition, have strong enough gravity to maintain an atmosphere despite factors like solar wind, yet these worlds lack atmosphere's because of the action of solar wind.
Rock planets are defined by their lack of either ice or oceans, combined with a weak or missing atmosphere. This is essentially the same properties as a Chthonian plant. I can only assume that Chthonian is its own type because it requires such high temperatures to occur, while rock is a valid type up to the snow line. The solar wind isn't the biggest factor there: its the temperature of the gasses. Just as earth is too hot and has too weak of gravity to hold onto hydrogen gas or helium, these planets are too hot and have too weak of gravity to hold onto organic elements as an atmosphere.

Quote:
4. The switch to Ice type worlds occurs earlier for Standard and Large Worlds then it does for Small and Tiny ones, it's rather weird.
Yeah, though if you think about what earth would like like in mar's orbit, it makes sense. Standard+ planets can form in front of the snow line and then accumulate a (geologically) thin coating of ice, while on the far side of the snow line balls almost completely made of ice can form.
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Old 08-24-2019, 07:52 AM   #3
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Default Re: [Space]Worlds Types And The Species That Live On Them

One thing to remember is that Space is ancient when it comes to the field of exoplanet studies. After all, you cannot use it to create Mega-Earths (such as Kepler-145b) or the extremely tight systems that orbit stars (such as the HD 40307 system, with its first five planets orbiting within 0.25 AU of its star). Of course, our technology is still new, we have only confirmed 3,000 or so exoplanets, so we might just be only able to find the weird systems for the most part right now (unless it was perfectly oriented with our system to allow for transit detection, we still could not detect our solar system).
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Old 08-24-2019, 07:54 AM   #4
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Default Re: [Space]Worlds Types And The Species That Live On Them

As an added note, the difference between Tiny (Ice) and Hadean is the reason for the lack of atmosphere. In the former case, it is because of lack of gravity. In the latter case, it is because of lack of warmth.
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Old 08-24-2019, 11:51 PM   #5
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Default Re: [Space] Worlds Types And The Species That Live On Them

Note that Garden Worlds only exist when they have life that injects oxygen into the atmosphere, since an oxygen atmosphere without plants to replenish the oxygen would quickly (in geological terms) lose the oxygen.

With that in mind, I find it somewhat peculiar that life that isn't water-based is assumed to exist in naturally-occuring atmospheres, as opposed to ones that would be unstable but for the presence of life that releases a highly reactive gas into the atmosphere. That has may or may not be oxygen; but frankly, there probably should be something like that, in order to fuel the alien biochemistry: something akin to plants, which take solar energy and use it to release the working gas into the atmosphere; and something like animals, which can operate on a high-energy basis because of the presence of a gas that's too reactive to be there naturally.
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Old 08-25-2019, 07:54 AM   #6
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Default Re: [Space] Worlds Types And The Species That Live On Them

Garden worlds require photosynthetic life and the presence of large amounts of oxygen in the atmosphere provides enough energy for multicellular life to evolve in the oceans and then spread to the land. Strangely enough, plants do need oxygen, just that plants produce net oxygen through photosynthesis, so you need microorganisms to have produced massive amounts of oxygen in the atmosphere before plants can evolve.
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Old 08-26-2019, 02:41 AM   #7
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Default Re: [Space] Worlds Types And The Species That Live On Them

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Originally Posted by ericthered View Post
Hadean and ice worlds have an interesting relationship. The main difference is that ice worlds have an atmosphere, while Hadean worlds do not. The exception to this is tiny (ice), which doesn't have an atmosphere, and I like to call tiny (Hadean). Once you make this switch, the reason for Large not having Hadean and tiny not having ice is more apparent: tiny planets are never big enough for atmosphere, and large planets always are.
The problem is that size differences are defined by that the planet can retain in it's atmosphere, not as frozen solids.
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Originally Posted by ericthered View Post
Rock planets are defined by their lack of either ice or oceans, combined with a weak or missing atmosphere. This is essentially the same properties as a Chthonian plant. I can only assume that Chthonian is its own type because it requires such high temperatures to occur, while rock is a valid type up to the snow line. The solar wind isn't the biggest factor there: its the temperature of the gasses. Just as earth is too hot and has too weak of gravity to hold onto hydrogen gas or helium, these planets are too hot and have too weak of gravity to hold onto organic elements as an atmosphere.
The thing is that unless my gut instinct is wrong there's a gap between between the liquid water zone, that is the distance from the star where a habitable planet may form, and the snow line.
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Originally Posted by ericthered View Post
Yeah, though if you think about what earth would like like in mar's orbit, it makes sense. Standard+ planets can form in front of the snow line and then accumulate a (geologically) thin coating of ice, while on the far side of the snow line balls almost completely made of ice can form.
I wouldn't call a planet covered in a thin coating of ice an ice planet as Space defines ice planets

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Originally Posted by AlexanderHowl View Post
As an added note, the difference between Tiny (Ice) and Hadean is the reason for the lack of atmosphere. In the former case, it is because of lack of gravity. In the latter case, it is because of lack of warmth.
Hadean worlds will have sheets of nitrogen ice while ice one's won't, it's not hard to believe that a Tiny(Ice) world as far from a star as a Hadean world will have notrogen ice.

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Originally Posted by dataweaver View Post
Note that Garden Worlds only exist when they have life that injects oxygen into the atmosphere, since an oxygen atmosphere without plants to replenish the oxygen would quickly (in geological terms) lose the oxygen.

With that in mind, I find it somewhat peculiar that life that isn't water-based is assumed to exist in naturally-occuring atmospheres, as opposed to ones that would be unstable but for the presence of life that releases a highly reactive gas into the atmosphere. That has may or may not be oxygen; but frankly, there probably should be something like that, in order to fuel the alien biochemistry: something akin to plants, which take solar energy and use it to release the working has into the atmosphere; and something like animals, which can operate on a high-energy basis because of the presence of a gas that's too reactive to be there naturally.
Quirk of the system of not fully thinking things out. Really need an astro-biologist to figure things out. That said they've probably already done that in the search for life.
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Old 08-26-2019, 07:34 AM   #8
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Default Re: [Space] Worlds Types And The Species That Live On Them

Quote:
The thing is that unless my gut instinct is wrong there's a gap between between the liquid water zone, that is the distance from the star where a habitable planet may form, and the snow line.

I wouldn't call a planet covered in a thin coating of ice an ice planet as Space defines ice planets
I'm not sure what your gap is in. Is it in the standard and large planets or in the tiny and small planets. I think you mean the standard and large planets.

Yeah, there are large differences between a rock with a frozen covering of ice and an ice planet with a "mantle" of liquid water many kilometers under an icy core. I'm just not sure that it matters most of the time. You have a smoothering atmosphere and a surface with features of ice.

If you want your system to distinguish (and I think you are going to have to expand the system anyways) you can certainly flag frozen rock planets as such.

Quote:
Quirk of the system of not fully thinking things out. Really need an astro-biologist to figure things out. That said they've probably already done that in the search for life.
Some of the garden worlds have have very foreign atmospheres. But the space system generator is rather biased towards water-based life. Which is intentional, space settings usually work better when you have lots of worlds fairly close to earth.

Page 140 of space has a table about which worlds can support which bases of life. Its designed to have you generate the aliens first and then the world they come from, but it can be inverted give each type of life you want a chance of having "THEIR" version of a garden world.
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Old 08-26-2019, 11:01 AM   #9
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Default Re: [Space] Worlds Types And The Species That Live On Them

I'm curious as to what sorts of “other versions of Garden Worlds” there might be. What are some alternatives to oxygen?
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Old 08-26-2019, 11:27 AM   #10
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Default Re: [Space] Worlds Types And The Species That Live On Them

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I'm curious as to what sorts of “other versions of Garden Worlds” there might be. What are some alternatives to oxygen?
Oxygen does have an advantage in being by far the most abundant oxidizing element.
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