Cubic Planet

[Stormgate]

In Sanderson books, mainly Cosmere, Sanderson does weird stuff with worldbuilding. Scadrial was a land of ash and brown plants, Roshar is hit by a hurricane every few days and has plants similar to a coral reef, Taldain has constant day on one side of the planet and night on the other. So, I decided to do something similar: make a cubical world. I think I've figured out how to use handwavium to get the gravity normal, but I need two things that I can't get right now: A map of what the world would look like if stretched over a cube (the Prime Meridian being part of one edge of the cube), and how the seasons would work. I currently have an idea where the orbit is changed slightly, so that it is winter on the whole planet or summer on the whole planet at once. However, I literally just realized that would do really weird things to the weather.

I don't have any idea how any of this could work, and I'm asking those with those skills to assist me in my worldbuilding (literally).

[king of nowhere]

huh... that's something i've never seen before.

 

first of all, the edges would crumble under the effect of gravity. a cube is an unstable shape under gravity, so the handwavium you need for that is really big.

Another thing is that atmospheric circulation would cause the edges to get more wheatered; sort of like if you pass sandpaper over a cube, the edges will get more scratched than the faces. so even atmospheric circulation would eventually yield a spherical planet, you need some handwavium for that too - nowhere near as much as you need to justify a cubic planet, though.

I have no idea how to convert a world map to a cube, unfortunately.

as for the wheather, the upper and lower faces would be completely wiithout sun for long amounts of time. i think they would be mostly, or entirely, covered with ice sheets. cold air coming down from those faces would go down towards the equatorial faces, so that there would be a temperate region near the edge and an equatorial region away from the edge. But then, compared to earth, i would expect the temperate area to be much smaller. On earth we have a gradual change in how much sunlight one place receives, with a gradual passage from tropics to temperate to artic. with a cube, the passage would be sudden, so there would be a large swath of equatorial climate on the faces that are directly exposed to the sun, an extreme polar climate on the top and bottom faces, and a small strip of temperate climate near the edges.

That assumption is based on the idea that the rotation axis passes near the center of two faces, of course. a configuration like this

O       □

where the O is the star and the □ is the cubic planet, the rotation axes being vertical on the page. If it is instead like so

O       ◊

with a vertex for pole, then all the climate would be temperate, because all the planet's surface would have the same inclination respective to the sun.

[Zathoth]

For the map

 

 

It is far from optimal, but neither is our  worldmap.

[ChickenPlague]

For the map

 

 

It is far from optimal, but neither is our  worldmap.

This one would at least have accurate sizes. Ynlike ours.

[Windrunner]

Just as a funny fact, Brandon has written about a cube-shaped planet in his writing exercise, "I Hate Dragons".

[Stormgate]

He doesn't get into the physics involved.

Also, I didn't think about the weather erosion. Thanks!

And the part about the top and bottom being covered with ice... That actually solves a small problem I had with my story. People need to get to Antarctica (which I am turning into a volcanic wastland, as opposed to the frozen wastland it currently is) and if it's the season where Antarctica is frozen... all the better.

The civilization at the North Pole will be interesting, though. Probably nomadic by necessity, as every spring they need to go to Russia, Alaska, Canada, and places in Europe because their home for the past months will be melting.

[Unodus]

Expanding on KoN's logic, how about this:

 

What if the planet was made out of a giant crystal shard? It wouldn't necessarily be a perfect cube- but the way crystal structures form, shouldn't it be possible to have a planet composed of straight edges?

Suppose, hypothetically, that there exists some ancient incredibly concentrated crystal structure floating in space which has been untouched long enough for it to grow a balanced structure- and then for whatever reason this hypothetical structure is shattered. I know crystals don't exactly grow in cubes, but a planet sized crystal fragment would have sharp edges like a cube. A solid crystal planet would explain why the planet doesn't erode into a sphere- and because light can travel through the planet, atmospheric circulation wouldn't have such a steep contrast.

 

Lets assume that over a long period of time, a layer of grit and water builds up on the surface of the planet due to meteors hitting the planet- thus making it capable of supporting life and plants. Even with most of the surface covered, light can still travel through the planet through the peaks (since grit would slide down the edges due to gravity), thus creating a translucent mountain range on each edge of the planet. 

 

Due to how thin the surface would be, deep rooted plants like trees wouldn't be as tall- a lot of the landscape would presumably revolve around flowing planes of wild grass, and because of that the most dominant wildlife would be mammals and serpents I guess. A society developing on the surface wouldn't have the luxury of metals or cellars given they wouldn't be able to pierce the planets surface- but perhaps since the planet was made by a giant crystal shattering, the civilization thrives on scavenging smaller crystal fragments that frequently fall to the planets surface. Since these crystals are hypothetically almost unbreakable, they'd play a huge part in the society that develops- imagine a religion that literally revolves around their gods giving them practically unbreakable crystal to make tools. 

 

I dunno, just some ideas :V

[Oversleep]

Would the Cube rotate? Because rotation of the planet is responsible for flattening of the planet.

[king of nowhere]

as a crystal grows in size, the gravitational force increases more than the force of internal coesion. that's a consequence of the square/cube law. astronomical objects larger than 500 kilometers are roughly rounded because gravity is greater than the material strenght. That applies to rock and ice.

On the other hand, if a giant, planet-sized diamond existed, then maybe a diamond would be hard enough to not be crushed under its own wheight. i don't know how to calculate that, but it's the hardest material and also fairly lightwheight - less gravity to counteract. a planet formed by a giant diamond could be explained with the physics we know.

[Master Elodin]

Or a god could be behind it all.

[Straw]

Or a god could be behind it all.

Allow me to present.... Cubeinatior God of cubes!

[Stormgate]

Not exactly a god, more similar to a Shardholder.

I had no idea who Sanderson was when I got the initial concept, but the cubic planet was a recent addition.

The planet would rotate, necessarily leading to really weird mornings and evenings.

Basically, it's Earth in a few million years. The deity-level powers on the planet have long since caused the apocalypse, and reformed the world into a shape that indicates that there is a power that has dominion over that area. Humans have responded by harnessing the powers of these powers, rebuilding into mostly medieval societies.

[Eagle of the Forest Path]

And the rotation axis? Face-to-face or vertex-to-vertex? As King of Nowhere already said, that's going to be really important to work out climate, polar regions, day-night cycle, and probably a whole lot more.

 

How about the rotation axis' angle relative to the ecliptic plane? (This would also affect the polar regions and the seasons on the whole cube)

What shape is the moon, if it still exists?

 

You mentioned jerry-rigging gravity a bit, does gravity still point to the center of the planet, or is it right-angles to the faces of the cube?

[Stormgate]

Gravity pulls towards the face you are facing. The farther you get from the ground, the weaker this magical gravity becomes, going more towards the center of the planet. The moon is normal sized and shaped. The people would probably be freaked out if they knew that it was possible to walk on the moon.

I've envisioned the North and South poles being in the middle of two of the faces of the cube, probably with some tilting to allow seasons to happen. I'm not sure what the faces would look like, which is the main reason for this topic.

[Oversleep]

So how gravity works on edges/corners?

[Stormgate]

Well, you can straddle the places where the gravity changes, but stay for too long and you get Border Sickness. Gravity otherwise is normal(ish), and I kinda want an action scene on one of the edges.

[Young Bard]

More stuff to look out for with your handwavium.

 

I'd draw six separate maps, with arrows saying "Leads to (x)". I'm imagining that the inhabitants, assuming the cubic thing is common knowledge, would have names for each of the six faces, presumably based off it's environments/societies/species.

 

When you say cubic, do you mean exactly cubic? Or is there a little wiggle room? For example, do you have any mountains beside the corners.

[Stormgate]

Roughly cubic, there is a bit of wiggle room in mountainous areas. My main problem is I don't know which parts of Earth would go on which parts of the map.

[king of nowhere]

More stuff to look out for with your handwavium.

 

good catch. I hadn't thought that with normal gravity the edges would stick out of the atmosphere. that article refers to a planet with the rotational axis passing through the corners, not the middle of the faces, but the part aboout the atmosphere is true. After alll, a cubical planet can be considered like a normal spherical planet with 8 mountains thousands of kilometers high.

[Stormgate]

Hmmm... More atmosphere? 

I'm having some trouble with this one.