AERLAAN – A playground built for a muse

[PaGaN]

Hello all and a quick thank you for stopping by!

As I mentioned in my “Introduce Yourself” post, my main reason to return to world-building is provide myself with an inexhaustible source of inspiration for various other artistic projects (though mostly painting). There is nothing more frustrating than staring at a blank canvas/screen whilst you berate yourself for not being able to think of anything cool to breathe life into.

So, what are my goals? Well, I want to build a world that is, for the most part, coherent and believable. And when I say believable I suppose I am more specifically referring to ecology, climate and biomes. No floating mountains, no rivers flowing uphill, no jungles in the middle of a desert etc…

To that end I intend to follow Pixie’s climate guide at least up to calculation of precipitation patterns for the world and then will most likely switch across to Azelor’s guide to figure out the climate zones. When it comes to the actual biomes I will probably refer to Mbartelsm’s very handy appendix.

Know upfront that Yes, I have taken artistic license in a couple of areas and I will sacrifice a little bit of plausibility for a big dollop of “Cool” each and every time.

I love fantasy so Aerlaan will grow up and be all sassy in that particular genre but will also have a few elements of a powerful long forgotten technology from an antediluvian past that will honestly have nothing to do with justifying my aforementioned “artistic licenses” (WINK WINK).

So, with that being said let’s begin at the macro level shall we? Let me present to you the Bahl System: NOTE – She isn’t finished and is likely to have a handful more planets and moons over time.



OBVIOUS DISCLAIMER 1: this is NOT to scale…LOL. I will be designing a relative size chart and relative distance chart soon(ish).
OBVIOUS DISCLAIMER 2: I am not an Astrophysicist. I know that there may well be aspects of this system that should not work. Remember that ancient tech I told you about??? Good.

Let’s take a walk:

BAHL:
She is a K class yellow sub-giant star who has firmly started her journey of transformation into a red-giant. Her habitable zone is likewise significantly pushed out farther than ours. In human years she is rapidly approaching retirement but has a good number aeons left in her. Bahl has already consumed her inner most planet, a now unknown small rocky world that no one in the system will ever knew existed (well, maybe not “no one”…WINK WINK). What does this mean for Aerlaan? It means that Aerlaan has a gorgeous warm golden “large and in charge” mother sun looking over her.

SKAH:
Whilst not yet consumed by his mother, this innermost planet is the second casualty of Bahl’s expansion. Skah was, in a now distant past, a handsome, habitable and inhabited world. Skah is now a barren tortured rock with almost no atmosphere left. His surface is broken by huge molten rivers that continuously form, bleed and subduct as the encroaching sun exerts increasingly disruptive forces upon this long ago paradise.

AERLAAN (& MOONS):
Here she is, the new golden child of the system brought in from the cold.



As Bahl grew, her warmth and light reached further out thawing Aerlaan and bringing her to life. Aerlaan has had at least 500,000,000 years of being inhabitable and has developed a very rich and diverse ecosystem (with a little accelerated help…WINK WINK).
Here are some stats:

AERLAAN
A) Orbital Period = 432 days
B) Degrees/Solar Day (DSD) = 0.8333
C) Solar Day = 24.00 hours
D) Sidereal Day = 23.57 hour
E) Diameter = 5,729,58 miles
F) Circ = 18,000 miles (Earth is 24,901, Mars is 13,263)

Valhenta
• Synodic Period = 6 days
• Sidereal Period = 5.917
• Synodic Degrees per day = 60.8333
• Aerlaani Orbital Degree/Period = 5
• Periods/Year = 72
• Semi Major Axis = 10,000 miles
• Diameter = 350 miles

Olarune
• Synodic Period = 16 days
• Sidereal Period = 15.43
• Synodic Degrees per day = 23.3333
• Aerlaani Orbital Degree/Period = 13.333
• Periods/Year = 27
• Semi Major Axis = 25,000 miles
• H) Diameter = 800 miles

Therandor
• Synodic Period = 144 days
• Sidereal Period = 108
• Synodic Degrees per day = 3.333
• Aerlaani Orbital Degree/Period = 120
• Periods/Year = 3
• Semi Major Axis = 80,000 miles
• Diameter = 1500 miles

The intricate interlocking precision of these celestial bodies are a favorite subject of Aerlaani philosophers who have been known to debate for entire lifetimes about the presence of an intervening hand that would have caused such a statistically unlikely array of such synchronicity (LOL…WINK WINK).

Why do the moons nest so precisely? Because new year on Aerlaan is awesome and marked by a great convention of the 3 moons above the equator. And this occurs EVERY YEAR like clockwork. Why are the moons at the size and distance they are? Because I think that there is nothing cooler than seeing giant moons coming up on a horizon. It’s an old sci-fi trope I know, but it’s STILL cool.
If you want a little more flavor then below you can find the Aerlaan “Ætheric Calender” (I’ll get into what “Æther” is later).



SHOM
(So far) the only gas giant in the system, Shom is truly a giant at about 15 times the size of Aerlaan. This big blue beauty also resides in the habitable zone. what does this mean? well it means that Shom is also mother to two large terrestrial and tidally locked moons that are also teeming with life (NOTE: I am also likely to throw a few more barren moons in there for good measure).

Pernessa
Shom's closest and most hospitable world. Life is complex and beautiful on this moon though largely confined to the planet facing side. She orbits her parent planet every 14 days and so does not have to endure as wildly fluctuating extremes as her brother moon, Elwynn. The side of Pernessa that faces away from Shom is somewhat less friendly to life however with much more extreme differences in temperature and climate (Roasting then scorching on a significant scale).

Elwynn
About twice the size of Pernessa, Elwynn is the big brother and, in the past, has taken many a beating for his little sister. His surface bear the scars of many huge impacts that have provided him with water but also, over time, unbalanced his atmosphere. Whilst Elwynn supports life, it is not as complex or rich as Pernessa. Elwynn orbits Shom every 37 days.

Storms on both of these moons are certainly something to see.

For the remainder of the system, i will more than likely add some more children to this family as they come to me but for now, that's about it. With that being said, that’s it for this post. Next post I will show you the actual landmasses, tectonics and a VERY quick and dirty elevation map. Also, what I envision Aerlaan’s atmospheric circulation would look like (spoiler alert: I have small Ferrel Cells…LOL)

See ya on the flip side!

[tatteredglyph]

I hope it's okay I respond to what you've posted so far.

This is honestly very inspirational. The detail and work you've put into this so far is awesome, and the hard work is easy to see. It's paying off big time, and I've got to say, I'm not particular about the details (I honestly don't know what a locked moon is right now, but I'm gonna be doing more research) but it makes me want to learn more about this project of yours. Since I'm new, I can't really critique too much about things right now, but I kind of want to just spread positivity around at the moment. I think you're on the right track - I think it's okay to have some suspension of disbelief, it's fantasy after all. There's leeway for some disbelief in here, and I think you have a pretty good balance of it.

I also love the descriptions of the planets so far, and I'm eager to see what comes of this project of yours.

[PaGaN]

I hope it's okay I respond to what you've posted so far.

This is honestly very inspirational. The detail and work you've put into this so far is awesome, and the hard work is easy to see. It's paying off big time, and I've got to say, I'm not particular about the details (I honestly don't know what a locked moon is right now, but I'm gonna be doing more research) but it makes me want to learn more about this project of yours. Since I'm new, I can't really critique too much about things right now, but I kind of want to just spread positivity around at the moment. I think you're on the right track - I think it's okay to have some suspension of disbelief, it's fantasy after all. There's leeway for some disbelief in here, and I think you have a pretty good balance of it.

I also love the descriptions of the planets so far, and I'm eager to see what comes of this project of yours.

Hey Tatteredglyph!

Thanks for the kind words

I've got to say that seeing all the amazing work flying around this guild has got me super motivated to develop this project so you'll hopefully be seeing Aerlaan unfold over the next months (or years???...LOL).

I'll be posting some more development today.

For me, I think, the major chunk of the work is going to be figuring out the climate zones and subsequent biomes. THAT is going to take some time. Before I even get to that though i'm going to be needing some feedback on the groundwork to make sure everything is copacetic before i climb the Everest of climate design...LOL.

Re: Tidal Locking - is when a smaller orbiting body (like a moon or a planet orbiting VERY close to its star) is prevented from rotating by the larger body it is orbiting. The smaller body kinda gets deformed a little and becomes very slightly "egg shaped" with the pointy end pointed toward the larger body. The satellite will "try" to rotate but the larger body will continuously pull the "point" back toward the larger body. Eventually the smaller body just stops trying and becomes "locked", at least this is how I understand tidal locking to work...LOL.

BTW, I just quickly swung by your Faladriand thread and will swing by again later for a deeper look and a thumbs up. i have a tip for naming that you might find useful! well, not so much of a tip but more of a practice so that you will always have a source of names to draw from.

Catch you later!

PaGaN

[PaGaN]

AERLAAN – “What’s Shakin” and “Under Pressure!”

Hello again!

The last post laid out the Bahl system that is home to Aerlaan whilst providing some details about the world herself, namely broad planetary and lunar information.

Today I want to post more specifically about Aerlaan and present pretty much where I am at so far which is nailing down the tectonics which in turn defined the land and water masses. Once this was done I could work on conceptualizing the atmospheric circulation which then allowed me to knock out a rough map of the summer and winter pressure zones.

So, let’s crack on.

1) WHAT’S SHAKIN??? (Aerlaani Tectonics)

Here are the land and water masses for Aerlaan:



And here are the tectonic plates and plate movements that gave rise to the above:

KEY:
Red = Subduction Zone
Yellow = Transform Boundary
Blue = Divergent Boundary
Dotted Boundary = Old fault/fused plate
Arrows = direction of plate movement and rough speed (more arrows equal faster rate of drift)



Now this is where I would initially appreciate some feedback and input to start with becasue IF the tectonics are way off then the rest of the world will be out of whack and I will be staring at a huge amount of “do-over” which could be fun but would more than likely be annoying.

There is one thing to note about the tectonics that I have done intentionally for a desired effect and that is the large subduction zone running up the eastern landmass. The northern and southern portions of the colliding plates are subducting under each other in a kind of “S” configuration. This is deliberate because I want the resulting ranges to be home to some peaks that make Everest look like Ben Nevis (I’m talking about 47k).

One theory of why we apparently don’t have peaks that high on earth is because the weight of the resulting mountain kinda pushes down on the plate and forces it deeper into the mantle reducing the height. Another theory is glacial erosion eating away at the root of the mountains causing them to topple before they reach those heights. It is my thinking that if these plates subduct under each other then the interlocking will 1) fuse them and 2) buoy them up.

To get an idea of how the above tectonics would shake out I did the following VERY rough topographic map using a quick and dirty gradient map in Photoshop.



2) UNDER PRESSURE (Aerlaani atmospheric circulation and seasonal pressure zones)

Given that Aerlaan is a world somewhere beteen Mars and Earth in size this raised the question of what happens with the atmospheric circulation on a planet that size?

Mars has a weird setup in that it only has a single Hadley cell and two polar cells. Earth has the 3 cells per hemisphere that we are used to.

I had already gone through a previous version of Aerlaan’s atmospheric circulation using an “earth normal” model but then ended up thinking that what would happen if, because of her size, Aerlaan only possessed sort of “proto” Ferrel cells? I envisioned small cells that were kind of squashed up against the polar cells in northern summer and a little more relaxed as they crept south in northern winter.

Here is what I mean:

Summer Atmospheric Circulation


Winter Atmospheric Circulation


The very tight zone between the mid latitude high and low would cause a very sharp mainly north blowing wind that would rise rapidly and then fall back south when it reached the upper atmosphere after dropping its moisture. This sharp rise and fall combined with the Coriolis Effect COULD lead to that zone developing into a kind of humongous horizontal vortex of winds analogous of very rare “Roll Clouds” that we have here on earth but on a MUCH larger scale.


(image licensed for non-commercial reuse)

As an aside, I have actually seen a roll cloud here in Toronto whilst walking my huskies one evening. It was one of the times where the word “awesome” is used and meant in the literal sense. There were some kids nearby that were freaking out, pointing and shouting “it’s the rapture! It’s the rapture!” LOL. Granted, it WAS very supernatural looking and was just hanging there in the sky visibly rolling in a giant horizontal cloud cylinder. It was COOL!

Another cool effect of these that I envision could be the presence of a far reaching blanket of Asperitus clouds on the poleward sides of these fronts.


(image licensed for non-commercial reuse)

These asperitus clouds would be caused by the huge air turbulence and temperature differentials between the colder wetter northen air being kind of sandwiched under the warmer southern air being drawn up by the ferrel cell/polar cell boundary.

In winter as the ferrel cell moves south it will widen a bit and act almost like a normal ferrel cell as pressures ease up a bit allowing the band to “widen” a little and even allow some westerlies to form.

So, IF we accept my hypotheticals about the atmosphere then this leads to the following rough preliminary pressure maps for summer and winter on Aerlaan.

Summer Pressure Zones


Winter Pressure Zones


This is pretty much where I am at and I am holding there as any revisions are pretty easy at this stage. Next up will be wind and ocean patterns.

I had already figured this out for Aerlaan using a previous “earth normal” assumption but I think this could be more interesting.

So, all of you greater minds out there I am eager for your feedback and input.

Thank you.

PaGaN

[kacey]

This looks really interesting PaGaN I'll definitely be following this thread. I love how much detail you're putting into it and the calendar looks really neat.

[PaGaN]

Thanks Kacey! Much appreciated. The moons and calendar are probably one of my favourite aspects of this world (in case you couldn't tell by all the calculations that were involved to get the moons to line up perfectly each year)

[randigpanzrall]

Hey PaGaN, intersting project, even if I don´t have an idea, where it will go. I will look upon from time

[PaGaN]

Thanks randigpanzrall.

Lets call it a Journey of Discovery...LOL. Gods only know where she'll end up.

Should be interesting.

[Azélor]

There is one thing to note about the tectonics that I have done intentionally for a desired effect and that is the large subduction zone running up the eastern landmass. The northern and southern portions of the colliding plates are subducting under each other in a kind of “S” configuration. This is deliberate because I want the resulting ranges to be home to some peaks that make Everest look like Ben Nevis (I’m talking about 47k).

The maximum height is limited by several factors. The most important is the hardness of the rock. It compresses and expands outward if the pressure gets too high.
Mt Everest is not far from the theoretical limit. Olympus Mons on Mars is 3 times higher simply because the gravity is 3 times lower than on Earth. Not a coincidence.
Also, erosion grinds the mountains overtime.

In order to have something much higher you would either need lower gravity.
Or mountains made of another harder material that could resist the pressure like diamond.
Both options aren't plausible much.

[PaGaN]

The maximum height is limited by several factors. The most important is the hardness of the rock. It compresses and expands outward if the pressure gets too high.
Mt Everest is not far from the theoretical limit. Olympus Mons on Mars is 3 times higher simply because the gravity is 3 times lower than on Earth. Not a coincidence.
Also, erosion grinds the mountains overtime.

In order to have something much higher you would either need lower gravity.
Or mountains made of another harder material that could resist the pressure like diamond.
Both options aren't plausible much.

Hi Azelor.

Thanks for coming by, i'm honored.

You make a good point (as ever) and i'll probably be chewing on this for a day or two to figure out how attached i am to the idea. I have a feeling that Dwarves would be all in for a mountain made of diamond but seems as there won't be any Dwarves on Aerlaan...

Another thing about Olympus Mons, that also nods your point, is the sheer area of the thing. That mountain is seriously bottom heavy.

Oh well. I guess a continent spanning mountain range tortured by a gaggle of Everests would still be a sight to see

Again, thank you for stopping by and hopefully you wont mind me hitting you up when i get to that other Olympus Mons...CLIMATE!

PaGaN