Tellurus: a worldbuilding project

What color scheme should Tellurus use?


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I personally like kings lists-they help me to think about how these different rulers would react to the larger historical events and it helps to flesh out details to the polity.
 
Well, I was bored and I had time so I made the thingy from a few weeks ago better. Each lighter/ darker shade of the same color denotes the reign of a king. And the striping denotes vassal rulers of the smaller stripe. Some of the longer spaces may mean there are no known kings, however. Also, everything in Kadimar is wrong so ignore that part. As always questions are welcome.
kyngir rulers thingy.png
 
Honestly? just eyeballing it and drawing inspiration from real-life paleogeography. Also GProjector.

Yeah but im still not sure how to incorporate them yet.

Quick question for everyone, would you rather I list every ruler of the major nations in the timeline or just the ones that are important? I'll eventually post king lists too if people are interested.
Well you could make it so they are seen as just a different "tribe" of humanity since they are so similar and can obviously procreate with humanity. There would be some genetic differences of course, but not anything too wild. If you wanted to go into a more lore aspect, Neanderthals could be recognized as different and oppressed in certain places (not because they are seen as genetically different obviously but rather the view that they are a different "tribe") and other places seen as sort of special. (think of the notion of royal families and that sort of bloodline) You would also have to geographically separate them from regular homo sapiens in some way to prevent the intermixing that would just create, not Neanderthals' on a large scale. This would occur anyways but if you wanted to keep actual Neanderthals alive than this separation would probably have to occur.
 
i have been stalking this project for a while for over a year before making an account - absolutely love it.

However, I saw that the last time you posted an update of the HQ map redraw on this thread a little over 3 years ago, though you were active on this website not long ago. Was wondering how the progress is going, because this just looks awesome!
It is probably too much to ask, but I was wondering if you could show some more progress of this here or if it's already finished, unless it is already posted elsewhere?
 
I haven't read everything (there are 55 pages in this thing, sheesh) so apologies if some of the old info here has been changed. But, I checked visually what planets were what sizes, assuming Tellurus is exactly the same size as Earth. Forgive my handwriting.

Also, I'd like to help! I'm a bit of a space nerd, and I love me a good star system. I have a physics simulator called Universe Sandbox, which only runs on newtonian physics but it's pretty accurate still. Can be used to see if orbits are stable or not (and your solar system is indeed stable, at least over the 3000 year simulated time I tried). Moons not added in yet, since idk their orbits, but the only ones which really need to be tested are Tellurus and Themis.

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I do have some things of note about those moons, though. The inner planets are fine, but the gas giants are interesting. You're using Saturn and Uranus (and the other two ig) as templates. While this is fine, it's important to know their origins. The Uranian moons were most likely formed from the same collision that knocked it onto its side. This is obvious when looking at Miranda and its bonkers topography. If Hemera didn't experience what Uranus did, just know that the moons won't be the same. As for Caleus, I don't know if you're gonna give it rings. If you don't want to outright copy Saturn or Uranus, then I'd give Hemera some rings and have Caelus be much more visually interesting than Saturn is irl. One suggestion would be massive white storms that look like milk swirls in coffee. Saturn has these every decade, so it isn't baseless.

But I'm mainly intrigued by Eirene. It's larger than mars, and has LIQUID water on its surface. Moons which form past the frost line are mostly made of ices, like water, so this ocean will be insanely deep. There won't be any landmasses on this moon, and if it recently thawed, you're looking at a thick atmosphere of mostly water vapor and whatever else was in the ice crust, as well as what radiation will break those molecules into. The thunderstorms here would be trvly mighty, I can only imagine. There's also the question of where it gets its energy, what keeps these oceans warm. Maybe some series of collisions, like passing through a dense planetary ring of Themis (if it has one), or a series of passes by Thallo. Although if the latter was the case, Thallo would be an absolute mess well before Eirene saw its first thunderstorm.
 

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Yes.

As such, having a 3:4 resonance makes sense.
Unfortunately not.

At least, according to Universe Sandbox over a time period of only 300 years, which was how long it was stable before Eos (yes, the smaller one) kicked Ersa out of the system and into an orbit around Lurus. The last resonance option of 1:2, though, is indeed "stable" over the 3000 years i tried for. Emphasis on those quotations, though. The moons don't follow a track, and they constantly jostle one another back and forth, albeit rhythmically. Eos always has an elliptical orbit, while Ersa fluctuates between further and closer (more circular) orbits. This is assuming Ersa orbits at lunar distance (on average), and Eos take half the time Ersa does to orbit Tellurus once (aka ~ 237,500 km, with a notable fluctuation). These two moons, ESPECIALLY Eos given its size and Io-like predicament with the other moon, will be seismically active. I don't know exactly how seismically active, but it wouldn't be unrealistic to say there are a few volcanoes on the bugger.

Also, apparent sizes from the surface of Tellurus. Pretty much the same size, and much smaller than the moon. I got these sizes from the sizes of the moons comparison chart. Don't mind the textures for the moons, I edited preexisting saturnian moons. Oh, and you also won't ever get a total solar eclipse.

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(Edited; I confused mass for radius last time. Fixed it. Note that Eos is about the same size as Ceres, but a bit denser)
 
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Wow, this still exists? I first saw this in... late 2019 I think, from a random google search
And honestly I really, really loved it back then
Now I am trying to do my own conworld project thingy but still, wanted to thank you all for inspiring me
 
Spitballing ideas time.

Star systems are typically interconnected, i.e. events and bodies affect or are affected by others. Commonly known examples being how Mars was dwarfed by Jupiter, the Earth-Theia collision, and of course the late heavy bombardment, which involved almost every planet in the solar system. There will be plenty of events, as well, unless your focus is a tiny moon. Here are a few of my ideas, given the write-ups for the worlds posted by Frank. These all go for the inner system, btw.

Phlogis and Semreh.
These two could be the result of a collision between two ancient worlds. A young Semreh, much like (a theory of) young mercury, smashes into another protoplanet. This could not only strip much of the crust and mantle from the planet, leaving it iron-rich as the core inherits a larger portion of the planet's volume, but it could also release plenty of ejecta into orbits around Lurus. Phlogis would be the majority of this material, and thus be iron-poor. Young Semreh and young Phlogis would've therefore had to have been much larger compared to what they are today, since Semreh would've been stripped and Phlogis... well, yeah.

The terrestrial moons.
Eunomis is far from enormous. Heh. It's the size of Titania, which is quite a bit smaller than our moon. If it was formed the same way our moon was (specifically the Synestia hypothesis), then Eunomis would have been much larger. This goes for the Tellurian moons as well. The fix here would be the classic big-impact-hypothesis, where Theia analog hit these planets at a glancing blow and the resulting moon is much smaller, since the impactor's size has more influence (not that it didn't anyway, but a synestia is a synestia). These impactors could've been much lighter. Very likely, considering how close Aerehtyc and Tellurus orbit to one another. Could be all sorts of chaos happening in that region.

The binary.
Oh boy oh boy, binary time. These are odd. As evident in our solar system, planets tend to form with most of their mass concentrated in... well, their mass. None of the rocky planets IRL have natural moons of their own because they're so small. Gas giants are essentially orbited by dust particles, in comparison. Pluto, the largest binary we (I) know of that isn't a star binary, is well into the kuiper belt where the circumstances are much different from the dry inner system. And even then, Charon likely formed from yet another impact! An impact of its own seems to be the only explanation for how Thrax and Adrestia formed. And if they're both the size of mars, and accounting for how much mass must've been lost to space during this impact, this would've been the second most violent event in the whole system (aside from the Hemera toppling event, if you're gonna pull a Uranus.)

How it all fits together.
You could connect it all into one continuous event, the whole inner system. One last thing I haven't touched on is how the fuck Aerehtyc and Tellurus orbit so close to one another. Sure it's stable, but how did they form that close? Unless they didn't. Maybe there was a sixth rocky planet which shepherded the orbits. Eventually, though, it would've been shifted itself. Some sort of insane event, which started it all, obliterated Super-Theia into fragments or just knocked it into a new orbit, still with plenty of bits strewn about. Maybe a collision from a flyby rogue planet past escape velocity. This event would create all the bits necessary for the formation of all these moons.

Or, maybe it doesn't all have to fit together. Maybe an isolated event created Phlogis (btw it is very unlikely that Phlogis would form where it's literally evaporating at present day, planet formation is sensitive getting started), or Thrastia was split some other way. Although, there are a LOT of unusual things in this system. I love that, but unusual planet systems should have unusual origins.
 
Unfortunately not.

At least, according to Universe Sandbox over a time period of only 300 years, which was how long it was stable before Eos (yes, the smaller one) kicked Ersa out of the system and into an orbit around Lurus. The last resonance option of 1:2, though, is indeed "stable" over the 3000 years i tried for. Emphasis on those quotations, though. The moons don't follow a track, and they constantly jostle one another back and forth, albeit rhythmically. Eos always has an elliptical orbit, while Ersa fluctuates between further and closer (more circular) orbits. This is assuming Ersa orbits at lunar distance (on average), and Eos take half the time Ersa does to orbit Tellurus once (aka ~ 237,500 km, with a notable fluctuation). These two moons, ESPECIALLY Eos given its size and Io-like predicament with the other moon, will be seismically active. I don't know exactly how seismically active, but it wouldn't be unrealistic to say there are a few volcanoes on the bugger.

Also, apparent sizes from the surface of Tellurus. Pretty much the same size, and much smaller than the moon. I got these sizes from the sizes of the moons comparison chart. Don't mind the textures for the moons, I edited preexisting saturnian moons. Oh, and you also won't ever get a total solar eclipse.

View attachment 855733
(Edited; I confused mass for radius last time. Fixed it. Note that Eos is about the same size as Ceres, but a bit denser)
Is there a way for one of the moons to be Luna-sized/ the right distance for total solar eclipses?
 
Having been an observer of this thread for ages I just want to say I appreciate all the astronomical knowledge being shared in this thread. It's helping myself with figuring out how to plausibly get a terrestrial, livable world with two moons without having to say "magic lol."
 
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Is there a way for one of the moons to be Luna-sized/ the right distance for total solar eclipses?
Changing the size is the easy solution, but changing distance makes for an even more alien world. Plus, since the moons are lighter than ours, tidal forces won't have pushed them as far as OTL. (This technically means that Tellurus can easily have days shorter than 24 hours, up to maybe 16, but there are so many variables considering the extra moon that this is effectively optional.)

Below is what the simulation says for a total eclipse. For Eos, the distance is 105,000km or less, and with Ersa it's 200,500km or less. Note that the image below is only of each moon's total eclipse distance, and they are not shown in a 2:1 resonance (or any resonance for that matter, the ratio is gibberish).

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So, you have two options, if we keep the 2:1 orbital resonance:

1. Only Ersa gives totals
-Eos at 126.5kkm, Ersa at 200.5kkm

2. Both give totals
-Eos at 105kkm, Ersa at 166.5kkm

Note that both are far more stable than when the moons were further, since they're much closer to Tellurus and thus moving faster. Ersa always holds a circular orbit but fluctuates slightly while Eos always takes a more elliptical orbit, with an eccentricity of approximately 0.1 (it fluxuates, but that might be a consequence of Universe Sandbox running on newtonian physics and not general relativity). Both work well, I recommend either. Of course, this means that whichever you choose, you'll have at least one moon the same apparent size as Luna.
 
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Changing the size is the easy solution, but changing distance makes for an even more alien world. Plus, since the moons are lighter than ours, tidal forces won't have pushed them as far as OTL. (This technically means that Tellurus can easily have days shorter than 24 hours, up to maybe 16, but there are so many variables considering the extra moon that this is effectively optional.)

Below is what the simulation says for a total eclipse. For Eos, the distance is 105,000km or less, and with Ersa it's 200,500km or less. Note that the image below is only of each moon's total eclipse distance, and they are not shown in a 2:1 resonance (or any resonance for that matter, the ratio is gibberish).

View attachment 855999

So, you have two options, if we keep the 2:1 orbital resonance:

1. Only Ersa gives totals
-Eos at 126.5kkm, Ersa at 200.5kkm

2. Both give totals
-Eos at 105kkm, Ersa at 166.5kkm

Note that both are far more stable than when the moons were further, since they're much closer to Tellurus and thus moving faster. Ersa always holds a circular orbit but fluctuates slightly while Eos always takes a more elliptical orbit, with an eccentricity of approximately 0.1 (it fluxuates, but that might be a consequence of Universe Sandbox running on newtonian physics and not general relativity). Both work well, I recommend either. Of course, this means that whichever you choose, you'll have at least one moon the same apparent size as Luna.
Interesting. Thanks for figuring this kind of stuff out I would have been so lost trying to do it myself. I think I'll go with only Ersa being able to do total eclipses.
 
Interesting. Thanks for figuring this kind of stuff out I would have been so lost trying to do it myself. I think I'll go with only Ersa being able to do total eclipses.
No worries, I enjoy this. If you're going for only Ersa eclipsing Lurus, there are a few things to set in stone.

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Eos
Mass: 1.06E+21 kg
Radius: 480 km
Avg. Temp: -1.3°C
SM Axis: ~124,000 km
Pericenter: ~110,700 km
Apocenter: ~137,000 km
Eccentricity: 0.106
Inclination: ~5°
Orbital Period: 120 h

Ersa
Mass: 9.78E+21 kg
Radius: 917 km
Avg. Temp: -3.2°C
SM Axis: ~196,700 km
Pericenter:
Apocenter:

Eccentricity: <0.004 (fluxuates)
Inclination: ~5°
Orbital Period: 240 h

Pretty cool how the orbital periods are exactly 5 and 10 days. Funny thing about the resonance, too. Since the two moons are in a 2:1, they will always meet back at the same spot in their orbits, and only this spot in their orbits, ever. This happens to be when Eos is at its closest to the planet, so your double-moon transits will be when Eos is largest. Then, of course, their direct opposition will be when Ersa is on the other side of the planet while Eos is again at its closest. The simulator also says that Eos generates 23.6 GW of tidal heat energy during its closest passes to Tellurus, though I'm not sure exactly how to translate that into specific types of seismic activity. For reference, the simulator also says that Io generates up to 3.7 TW, Ganymede 27 GW, and Luna up to 6 GW. Oh, and Eos's Great Crater will be a weak point in the crust. Do with that what you will.

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And lastly, the eclipses. While it is true that Eos is too small to fully block the star, and Ersa is, I was surprised at how close it was. As you can see, all 3 are almost the exact same size. I specifically chose to show Eos at its closest and Luna at its furthest for the apparent size comparison, not only because you will only ever see them this close together when they are these sizes. While it is the shortest point in its orbit, as all orbits have the shortest time spent the closest to the orbited mass, the Eosian pericenter makes it appear larger than Luna when it is at its furthest. You could call it an Eos Supermoon (Ersa basically stays the same size).

Yes. If they exist, they will be exceedingly rare. The conditions to see one would require Eos to be at its absolute closest point in its orbit, which will be fleeting, especially considering it only takes 5 days to orbit the planet. I'd imagine the planet itself would have to be at its furthest point from Lurus to give it that extra boost. And any total eclipse will be a part of a hybrid eclipse, where it starts and ends annular, but being directly under the peak of the shadow's path briefly gives full coverage. And speaking of briefly; because each moon has such a short orbit, any period of totality (for either moon) will be vastly shorter than our own eclipses. I don't think the longest Eos eclipse would ever last longer than 20 seconds. And you can still say that Eos never gives a total eclipse, sure. I'm just saying that if you want to spice things up, Eos could put on a once-a-millenium show for a short while. Could be interesting. In any case, here are your moons.
 
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