[Space/Thaumatology] Stargate: Fantasy - Worldbuilding thread

[Prince Charon]

So, for clarity, the reason I haven't posted the new question yet is that along with RL stuff piling up, I've been sick, and thus unable to work on it. I do intend to get more done, but how soon I do is something I can't predict.

[Prince Charon]

Wasn't sure that I'd have it ready this soon, but here it is. As previously suggested, we'll go back to the space forces discussion after deciding this one:

Frolechi Question VII

What is the Frolechi's planetary system like?

1. Just the one habitable planet with one or more small moons, plus asteroid belts and smaller planets, mostly good for mining at best.

2. One habitable planet, plus gas giants and smaller planets, similar to the Sol system.

3. Actually the Sol system, just in a different worldline (so Frolec is alt-Earth, or a place on alt-Earth).

4. As 3, but Frolec is (or is on) a much more habitable alt-Venus or alt-Mars.

5. There's a gas giant in the habitable zone, and Frolec is (or is on) the only Earthlike moon thereof (the sky would be spectacular).

6. As 5, but it has a few Earthlike moons, of which Frolec is (or is on) one.

7. Something else (please specify).

Please remember to include the number(s) of your preferred option(s) when you vote.

*******

Answer: The votes (if I'm counting correctly) are five for 6, two for 1, and one each for 2, 3, and 4.

[Kesendeja]

I love the idea of 6 so that's the one I'd go for. But 5 is good in a pinch.

[Fred Brackin]

4 or lower.

The more you look at 5 or 6 the more poorly they work (at least if the GG is like Jupiter and Frolech is in the position of Callisto). A smaller GG with a relatively more distant Earth-like planet as a Moon would at least work a little better. You'd probably need Frolech and the GG to be more like twin planets.

4 with its' more habitable Venus and/or Mars is not as difficult to arrange.

[adm]

6, I understand Fred's point, but hey, multiverse and magic. This should be a big clue that all is not as it seems.

Otherwise 2-4 works well.

[Varyon]

I'll toss in a vote for 6, but I'm interested in the reasons why Fred thinks it's unworkable. Is it an issue of relative size (that is, Earth-sized moons are simply too large for a Jupiter-sized gas giant)? Radiation? Simply having a gas giant in the habitable zone of a star (which implies some shenanigans, as from what I understand gas giants typically form beyond the snow line)?

[Fred Brackin]

Originally Posted by Varyon

I'll toss in a vote for 6, but I'm interested in the reasons why Fred thinks it's unworkable. Is it an issue of relative size (that is, Earth-sized moons are simply too large for a Jupiter-sized gas giant)? Radiation? Simply having a gas giant in the habitable zone of a star (which implies some shenanigans, as from what I understand gas giants typically form beyond the snow line)?

Well, we have t start somewhere and if we start with our Jupiter being the exemplar for the GG then the orbit of Callisto is the best place among the Gallilean moons for a habitable planet.

Callisto has a 17 day orbit and since it's tidelocked that means a 17 day day/night cycle. Right there you probably have to invoke the hypothetical process of atmospheric superrotation to keep the planet from being too hot/too cold.

Then since Callisto has a 1.8 million km orbital radius. That's better than 1% of Earth's orbital distance and the whole winter/summer distance is only about 2%.

Also, since it's tidelocked that means it's always the same place that's closest to the Sun every 17x24 hours. You also get he same place that's furthest away from the Sun though it may be in the GG's shadow when that happens.

So, in addition to any eccentricity int he GG's orbit you get something like n Summer and Winter every 17 days.

Note that even Callisto (most distant of Jupiter's big moons) is still getting the particle radiation that Earth does. Move Jupiter 5x closer to the Sun and it gets more particle's in its' magnetosphere to start with. Being tidelocked migth mean that Frolech had no magnetic field of its' own (though a thicker atmosphere might compensate).

Finally, I would note that only about half of Frolech would have a spectacular sky view. Because of that tidelocking again half the planet never sees the GG. The other half always sees it.

<shrug> It all gets rather complicated and I don't much believe in habitable GG moons any more.

[ericthered]

1, 6, or 7:

7a: as four, but its not an exact alternate of the solar system
7b: Two planets rotating each other very closely. You can say "moon", or you can say "Binary Planets".
7c: Its like the Trappist-1 system (or the wild dreams of it), and it has three habitable planets in close arrangement around a red dwarf in resonance orbits.

Considering Tide-locked orbits, I think leaning into that could be fun. I don't think a 17-day rotation is going to be that bad, considering the temperature ranges we get in our northern latitudes where the sun doesn't rise for a month or more.

The particle radiation is a bigger deal, but that's something I'm happy hand-waving for here.

[Varyon]

Originally Posted by Fred Brackin

Well, we have t start somewhere and if we start with our Jupiter being the exemplar for the GG then the orbit of Callisto is the best place among the Gallilean moons for a habitable planet.

Callisto has a 17 day orbit and since it's tidelocked that means a 17 day day/night cycle. Right there you probably have to invoke the hypothetical process of atmospheric superrotation to keep the planet from being too hot/too cold.

Then since Callisto has a 1.8 million km orbital radius. That's better than 1% of Earth's orbital distance and the whole winter/summer distance is only about 2%.

Also, since it's tidelocked that means it's always the same place that's closest to the Sun every 17x24 hours. You also get he same place that's furthest away from the Sun though it may be in the GG's shadow when that happens.

So, in addition to any eccentricity int he GG's orbit you get something like n Summer and Winter every 17 days.

Note that even Callisto (most distant of Jupiter's big moons) is still getting the particle radiation that Earth does. Move Jupiter 5x closer to the Sun and it gets more particle's in its' magnetosphere to start with. Being tidelocked migth mean that Frolech had no magnetic field of its' own (though a thicker atmosphere might compensate).

Finally, I would note that only about half of Frolech would have a spectacular sky view. Because of that tidelocking again half the planet never sees the GG. The other half always sees it.

<shrug> It all gets rather complicated and I don't much believe in habitable GG moons any more.

Maybe Frolech confuses SGC quite a bit. First off, we might posit that the Earth-like moons orbiting the gas giant actually aren't in the same plane as the solar system itself (I should clarify this to mean same orbital plane, they're still in the same plane of existence) - considering something major must have happened to throw the gas giant into the Habitable Zone, perhaps as a result of whatever this was (a massive collision, the gas giant actually being a rogue planet that was captured, a bored Ascended before they had rules against such drastic actions, etc) the planet is functionally "on its side," with the moons orbiting at a roughly constant distance from the system's star. That prevents the drastic seasonal effects (the gas giant might still get closer and further from the star, such that there are still seasons). That would also allow for the worlds to work even if tidally locked to the gas giant (which will result in one side always being exposed to the sun, one side not), but then again maybe the moons aren't tidally locked, and this is part of what confuses SGC. For the radiation hazards, perhaps again SGC is confused when SG1's Geiger counters reveal a comparable (or even lower) level of background radiation compared to Earth. The answer to the radiation issue - and probably the lack of tidal locking if you go for that - would probably be magic. Either the planet "naturally" has some of its mana shifted into forming an antiradiation barrier or there's something else going on - ancient interference by an Ascended (perhaps the same one who altered the orbit, if that's what happened), the Frolechi actually originating from somewhere else and using ritual magic to keep the barrier up, whatever.

[Fred Brackin]

Originally Posted by Varyon

the planet is functionally "on its side," with the moons orbiting at a roughly constant distance from the system's star. r.

if you mean like Uranus that doesn't work. Uranus is on it's side compared to most of the planets with a 90 degree tilt but it doesn't point it's "North Pole" continuously at the Sun. That changes where it's pointed by orbital position/time of year. I don't know if it's even possible to have such a "fixed" polar direction.

Over a few million (or maybe tens or hundreds of) years any moons of the polar-centric GG would end up in that planets equatorial plane and with their poles pointed in the same direction. So they'd have perpetual brigthsides/darksides and you'd really have to have that atmospheric superrotation.

It doesn't appear to take special events to "flip" planets like this though. Theory says Venus used to spin in the same direction as most of the planets until chaotic influences caused it to flip 180 degrees and spin "backwards".

This won't ever happen to Earth because our Moon stabilizes things.

If you want say "Magic!" just remember that it has to be really big Magic! and longlasting too.