Have you ever made a planet with desert poles and tundra equators?

[Shorty Lickens]

I never saw one in any RPG book of any kind. Nor have I seen a fantasy map of one. I have heard them described in some fantasy and sci-fi novels. But I never made one in the three galaxies, nor have I seen one mentioned here in the forums. But its possible I missed it.

Unrelated: What programs are you guys using for random map generation? A long time ago I downloaded some basic apps that I dont use any more. Cant even remember the name, but it was about 20 individual programs that did all kinds of random generation, even names.

[taalismn]

I find this webpage and site handy...https://donjon.bin.sh/world/

But I'm trying to picture a world like you describe....it would have to have massive axial tilt and the same side would almost always be facing its star, so only one pole would be classic desiccated hot desert. Otherwise you'd have to have some insane mechanism for both poles being desert.

[Nekira Sudacne]

I find this webpage and site handy...https://donjon.bin.sh/world/

But I'm trying to picture a world like you describe....it would have to have massive axial tilt and the same side would almost always be facing its star, so only one pole would be classic desiccated hot desert. Otherwise you'd have to have some insane mechanism for both poles being desert.

That's only true in single-star systems. There's probablly some configuration in a dual or triple star system that might result in this!

[taalismn]

Or maybe a a planet with an exceptionally dense ring system that blocks sunlight to an equatorial band enough for permanent ice to accumulate.

Larry Niven's 'Known Space' had Jinx, a planet that was so egg-shaped that its polar regions actually stuck OUT of its atmosphere.

[Warshield73]

First, former geography teacher here just has to clarify that there are polar deserts but I am assuming you mean a hot desert. LMK if I'm wrong.

I find this webpage and site handy...https://donjon.bin.sh/world/

But I'm trying to picture a world like you describe....it would have to have massive axial tilt and the same side would almost always be facing its star, so only one pole would be classic desiccated hot desert. Otherwise you'd have to have some insane mechanism for both poles being desert.

That's only true in single-star systems. There's probablly some configuration in a dual or triple star system that might result in this!

Not sure what configuration of stars would allow both poles to be a hot desert but I suppose it's possible.

Years...no I guess decades, wow I'm old...so decades ago I created Chandarra. This was an Earth type planet orbiting an extremely hot main sequence star.

It was almost on its side so while it wasn't tidally locked, rotated on it's axis, the north pole always faced the sun making it unbearably hot and completely dry, while the south pole was cold and dry with any precipitation going in that direction falling to the group as snow and locked into ice. The axial tilt meant that the north pole had just a sliver of night lasting a few minutes and in the south it had day for only a few minutes t any given location. The equator had massive storm systems from the two sides meeting so most people lived in mid latitudes on one side or the other.

This was the closest I ever got and I'm just not sure how you get both poles as hot deserts and the equator and tundra.

[ShadowLogan]

I never saw one in any RPG book of any kind. Nor have I seen a fantasy map of one. I have heard them described in some fantasy and sci-fi novels. But I never made one in the three galaxies, nor have I seen one mentioned here in the forums. But its possible I missed it.

Unrelated: What programs are you guys using for random map generation? A long time ago I downloaded some basic apps that I dont use any more. Cant even remember the name, but it was about 20 individual programs that did all kinds of random generation, even names.

Warshield's axial tilt is likely the most realistic way for this to happen. While this approach was for a single star system, it might work in a binary star system depending on the various orbits of the parties involved. That is my "gut" instinct on the matter. It might be worth researching the planet Uranus's "climate" given it also has a very high axial tilt (obviously it being a gas giant and its distance from the Sun might make the "warm" and "cold" climate areas less noticeable I don't know off hand, this planet has never been on my radar much).

Rings would be another way for that to happen, but you'd also need to be closer to the star in question.

Probably hard to track down, but Astronomy Magazine in the early/mid 90s did a series of "What-If" articles that involved changing certain parameters on Earth to see what would happen. I did not have the entire series, but IIRC it was excerpts from another source (IIRC axial tilt was one such "what-if", though I don't think I had that one).

I'd also point out that Earth does technically have "desert" poles since the qualifying factor is precipitation it receives (yeah even Earth's poles qualify as "desert"). The main difference between "tundra" and "desert" though is temperature (with some overlap).

That is if you are looking for a natural means to achieve the desired effect. Artificially I suppose you could do the same thing with solar shades (proposed for cooling Venus), solar mirrors (proposed for terraforming Mars, and small ones have been used at Earth to change illumination at night), or some other space born Mega-structure that can alter the approach of sunlight to the planet.

Of course, you could also just put an order in with Magrathea and let them worry about the details.

[Warshield73]

Rings would be another way for that to happen, but you'd also need to be closer to the star in question.

Rings are just to dispersed to have much effect on climate as far as I know.

The problem with the set up (both poles being hot deserts and the entire equator being cold tundra) is it just doesn't seem physically possible. Regardless of the rotation rate or even if the planet is tidally locked and the axial tilt, I just don't see how it's possible.

Now you could do this geothermally. A planet like earth with a slight or no axial tilt and at the outer edge of the habitable zone but massive geothermal activity at both poles. This means the equatorial regions would be frozen Hoth like, while the poles are mor Mustafar and the intermediate zones would slowly get warmer as you move towards the poles.

I don't know if this is what you are looking for but I think I am going to write up and use it in the future.

[ShadowLogan]

Rings come in a variety of types. If we're talking something like Saturn's Rings, yes they can cast a shadow on the planet which will impact climate. Something like the Rings of Jupiter or Neptune that are far more diffuse, I suspect not likely (IIRC Uranus is also in this camp) but can't be sure.

Arguably the easiest way to achieve what the OP is looking for is likely going to be artificial in nature as I said. Though you'd probably have to come up with a reason for bisecting the world like this.

[Warshield73]

Rings come in a variety of types. If we're talking something like Saturn's Rings, yes they can cast a shadow on the planet which will impact climate. Something like the Rings of Jupiter or Neptune that are far more diffuse, I suspect not likely (IIRC Uranus is also in this camp) but can't be sure.

Something the size of Saturn's rings on a planet the size of Earth would cast a shadow but ring size and density will be relative to a planets mass / gravity and so any ring system orbiting a terrestrial planet, as opposed to a gas giant, will be much smaller with a much lower density. Rings also flatten out to the plain of the planet's rotation so any axial tilt will reduce the shadow effect or even eliminate it entirely.

Again I think there are ways to get one pole as hot desert and the equator as tundra and be at least sci-fi reasonable but just don't see how you can get the other pole as a hot desert.

Arguably the easiest way to achieve what the OP is looking for is likely going to be artificial in nature as I said. Though you'd probably have to come up with a reason for bisecting the world like this.

A planet on the inner edge of the habitable zone so it is naturally a desert planet but it has a first race climate control devices around the equator but it is malfunctioning so instead of just cooling the equatorial zone it freezes it. Or, switch it around freezing planet with malfunctioning devices at the poles.

You could also go rifts, freezing planet but both poles are consumed by a giant rift that changes them to desert. Once you forget about making the idea at all rational the possibilities just open up.

[taalismn]

A planet on the inner edge of the habitable zone so it is naturally a desert planet but it has a first race climate control devices around the equator .

"Let's make a planet with blazing hot and dry poles and a glaciated equator, just for the hell of it! Something to boggle the minds of the younger races!"
"...you're a sick being, Reverso....

[ShadowLogan]

I did not mean Saturn's Rings being duplicated by shear size/volume. I meant in terms of quantity, Saturn has 7 main Ring GROUPS, Jupiter has 4 Rings, Neptune 5 Rings +4 partials, Uranus has 13 Rings. But Saturn is the most visible from Earth (via telescope). So I think it is important to recognize that Rings come in a variety of types and we need to be clear what type one is envisioning here.

Personally I wanted to avoid the "magic" aspect, even when considering artificial means though the OP might not have that preference.

You know I wonder if a "deformed" planet like Gobotron might get the desired results? Its equatorial zone is smaller than its polar regions, so the "polar" regions might cast shadows on the "core/equator". Granted I don't think Gobotron could happen naturally at that scale.

[Warshield73]

A planet on the inner edge of the habitable zone so it is naturally a desert planet but it has a first race climate control devices around the equator .

"Let's make a planet with blazing hot and dry poles and a glaciated equator, just for the hell of it! Something to boggle the minds of the younger races!"
"...you're a sick being, Reverso....

In my setting I have what are called Enigma Systems. These systems come in a few flavors but the major ones are:
1) Natural systems that have been rearranged in some impossible way or even combining several systems into something that would be impossible to achieve naturally but once it was in place is kept functioning by regular physics. Some were even harvested from other galaxies or dimensions. I have a quinary systems (5 stars) where each system is from a different dimension.

2) Completely created star systems. Some device (the Cosmic Forge) literally created the star(s), planets, even life but now that they exist they function according to normal physics. In my setting the Oni home system is like this, their goddess brought them too it after it was created.

3) One of the above, but the setup is unsustainable, so some device Keeps things running. I thought this was a good match for the Seljuk home system with the weird Gemini planet.

These are all great ways to mess with the scientists of the younger races especially because some of those systems where created after the First disappeared

I did not mean Saturn's Rings being duplicated by shear size/volume. I meant in terms of quantity, Saturn has 7 main Ring GROUPS, Jupiter has 4 Rings, Neptune 5 Rings +4 partials, Uranus has 13 Rings. But Saturn is the most visible from Earth (via telescope). So I think it is important to recognize that Rings come in a variety of types and we need to be clear what type one is envisioning here.

I was picking up what you were putting down. The problem is that size, density and even number of rings are proportional to the size of a planet. If an terrestrial planet like earth had rings they would be a thin line above the equator only about 30 feet thick that only widened to about 40 or 50 feet as it got to the edge, probably 20k to 50k kilometers out with anything further spun off into space in just a few short centuries, at least according to my research. If the planet is in the habitable zone then icy rings are unlikely as well with rocky remains of asteroids or moonlet being the most likely which would make them less visible with a reduced albedo. with all of this in mind natural planetary rings may not even be that visible much less able to cause a huge reduction in sun light.

If you assume that the rings do reduce the light from a star then you have axial tilt to look at. The only way for the rings to effect the equator is to have a zero axial tilt, but then the thickness means your effect a tiny sliver along the equator. if you want them to cast a larger "shadow on the planet then you have to give it a severe axial tilt and that means the areas effected wouldn't be equatorial, it would be more in the temperate zones.

Personally I wanted to avoid the "magic" aspect, even when considering artificial means though the OP might not have that preference.

You know I wonder if a "deformed" planet like Gobotron might get the desired results? Its equatorial zone is smaller than its polar regions, so the "polar" regions might cast shadows on the "core/equator". Granted I don't think Gobotron could happen naturally at that scale.

I also thought they were trying to do this without magic / god-tech but I just don't see how you do it.

[taalismn]

In my setting I have what are called Enigma Systems. These systems come in a few flavors but the major ones are:
1) Natural systems that have been rearranged in some impossible way or even combining several systems into something that would be impossible to achieve naturally but once it was in place is kept functioning by regular physics. Some were even harvested from other galaxies or dimensions. I have a quinary systems (5 stars) where each system is from a different dimension.

2) Completely created star systems. Some device (the Cosmic Forge) literally created the star(s), planets, even life but now that they exist they function according to normal physics. In my setting the Oni home system is like this, their goddess brought them too it after it was created.

3) One of the above, but the setup is unsustainable, so some device Keeps things running. I thought this was a good match for the Seljuk home system with the weird Gemini planet.

There's also:
a) Survivors from an earlier stage of the universe when physics were different.

b) Survivors of the -previous- universe that by some means survived a Big Crunch and then a Big Bang.

These worlds are usually fairly recent arrivals in the more congested/populated regions of the universe/galaxy, having avoided being destroyed by interactions with other worlds/cosmology by being for the greater amount of time off in the cosmic boonies.

[Warshield73]

In my setting I have what are called Enigma Systems. These systems come in a few flavors but the major ones are:
1) Natural systems that have been rearranged in some impossible way or even combining several systems into something that would be impossible to achieve naturally but once it was in place is kept functioning by regular physics. Some were even harvested from other galaxies or dimensions. I have a quinary systems (5 stars) where each system is from a different dimension.

2) Completely created star systems. Some device (the Cosmic Forge) literally created the star(s), planets, even life but now that they exist they function according to normal physics. In my setting the Oni home system is like this, their goddess brought them too it after it was created.

3) One of the above, but the setup is unsustainable, so some device Keeps things running. I thought this was a good match for the Seljuk home system with the weird Gemini planet.

There's also:
a) Survivors from an earlier stage of the universe when physics were different.

b) Survivors of the -previous- universe that by some means survived a Big Crunch and then a Big Bang.

These worlds are usually fairly recent arrivals in the more congested/populated regions of the universe/galaxy, having avoided being destroyed by interactions with other worlds/cosmology by being for the greater amount of time off in the cosmic boonies.

Need a "Mind Blowing" or "Over my Head" emoji for these. Interesting ideas for a Star Trek episode but not sure about it fitting in the cosmology of the Megaverse as it stands now. Also, if you have something that was created under a different set of physics enter our universe wouldn't the act of entry subject it to our physics? For that matter you could have the world exist inside a pocket dimension with alternate physics but I got the idea that the OP wanted a world for a Phase World like setting.

Still, a lot of interesting ideas in this thread.

[taalismn]

Well, you get a world that originated under a different set of physics, that planet could be slowly deteriorating or its technology is currently weak or ineffectual.
(In one L.E. Modest book, The Eternity Artifact, an expedition travels to a rogue planet covered with artificial structures of nonhuman origin. Based on what they discover, or DON'T discover, they speculate that the planet may be a survivor of an earlier period of the universe, and the technology on the planet no longer works because the aging universe has changed)
(A somewhat similar idea occurs in David Brin's Uplift Universe, where the expanding universe is causing a breakdown of the layers of hyperspace, preventing travel and certain forms of high level technology to cease working)

[ShadowLogan]

I did not mean Saturn's Rings being duplicated by shear size/volume. I meant in terms of quantity, Saturn has 7 main Ring GROUPS, Jupiter has 4 Rings, Neptune 5 Rings +4 partials, Uranus has 13 Rings. But Saturn is the most visible from Earth (via telescope). So I think it is important to recognize that Rings come in a variety of types and we need to be clear what type one is envisioning here.

I was picking up what you were putting down. The problem is that size, density and even number of rings are proportional to the size of a planet. If an terrestrial planet like earth had rings they would be a thin line above the equator only about 30 feet thick that only widened to about 40 or 50 feet as it got to the edge, probably 20k to 50k kilometers out with anything further spun off into space in just a few short centuries, at least according to my research. If the planet is in the habitable zone then icy rings are unlikely as well with rocky remains of asteroids or moonlet being the most likely which would make them less visible with a reduced albedo. with all of this in mind natural planetary rings may not even be that visible much less able to cause a huge reduction in sun light.

If you assume that the rings do reduce the light from a star then you have axial tilt to look at. The only way for the rings to effect the equator is to have a zero axial tilt, but then the thickness means your effect a tiny sliver along the equator. if you want them to cast a larger "shadow on the planet then you have to give it a severe axial tilt and that means the areas effected wouldn't be equatorial, it would be more in the temperate zones.

I think there might be a flaw here. That is the assumption of the World in question here has to be Earth-sized and have rings. Nothing in the OP suggests the planet's size or even habitability, only temperate zones.

I do think the Rings are the most "natural" way to get what the OP is looking for, but if we keep in mind we aren't constrained to having this world be Earth-sized that offers up some options for the rings.

What if we're dealing with a Super-Earth (which can be 2.5x Earth's radius and up to 10x its mass)?

What about a significantly "stripped" gas giant core? And the gas giant could have had an extensive ring system like Saturn. (NOTE: I have trouble seeing a natural phenomena to achieve this that doesn't also destroy the Rings, but Rifts aren't "natural"). Basically creating a Super Earth on Steroids IINM.

Getting away from the Rings option:
-"kissing" double planet (think some minor planets that are dumbbell shape, for full planets yeah long term viability is out I have no doubt due to physics unless something artificial is going on, but I have no idea off hand about short term viability)
-natural "dust cloud" at a Solar-Planet L1 point acting as a solar shade (again solar shades have been suggested for terraforming Venus and would be at the Sol-Ven L1, so L1 would be the right place). Depending on the size of the dust cloud at this point it might result in the desired effect (cooling the equator but not the poles), though the source of the DC in question is likely suspect
-large close orbiting "moon(s)". If the moon(s) has a large enough diameter and orbits close enough, tidal forces will be an issue, but such a large object(s) would cast large slow moving shadows over the planet below.
-planet's atmospheric composition either due to density (thicker at the poles than equator) and/or composition (what if the poles somehow had huge amount of greenhouse gases located at them, but not at the equator).
-planetary surface conditions (if the equator is more reflective than the poles)

[taalismn]

Getting away from the Rings option:
-"kissing" double planet (think some minor planets that are dumbbell shape, for full planets yeah long term viability is out I have no doubt due to physics unless something artificial is going on, but I have no idea off hand about short term viability)

Robert L. Forward's 'Rocheworld'; two close-orbiting egg=shaped worlds, pointy ends towards each other. They're so close they actually swap atmospheres and occasionally hydrospheres.

He managed to get three books out of the idea.

[Warshield73]

I assumed from the OP that they wanted something as natural as possible, i.e. no magic or god-tech, and I even assumed they wanted something habitable. Tundra and desert implies habitability since both require precipitation in some form and some form of atmosphere. It could be a different kind of habitable than earth standard but at the end of the day the physics don't line up to create a natural version of what the OP is asking for so we go to magic or magic tech.

[taalismn]

Or bad navigation.
"According to my map skills, we're currently at this planet's South Pole."
"...we're in the middle of scorching desert under a blazing sun...check your navigation again."

[Warshield73]

Or bad navigation.
"According to my map skills, we're currently at this planet's South Pole."
"...we're in the middle of scorching desert under a blazing sun...check your navigation again."

"I'm not asking for directions, I'm sure that south pole is around here somewhere."

[taalismn]

CLANG!

"FOUND IT!"

[ShadowLogan]

Getting away from the Rings option:
-"kissing" double planet (think some minor planets that are dumbbell shape, for full planets yeah long term viability is out I have no doubt due to physics unless something artificial is going on, but I have no idea off hand about short term viability)

Robert L. Forward's 'Rocheworld'; two close-orbiting egg=shaped worlds, pointy ends towards each other. They're so close they actually swap atmospheres and occasionally hydrospheres.

He managed to get three books out of the idea.

And in the News today I read that the "kissing" double planet might be a possibility, the Dwarf Planet Pluto and its main moon are theorized to have spent time "kissing", about 10-15hrs (due to Charon's size. There's mention of a "co-rotation radius" that would be a determining factor) before breaking off.

https://www.cnn.com/2025/01/10/science/ ... index.html
https://www.space.com/pluto-charon-kiss-capture

Or bad navigation.
"According to my map skills, we're currently at this planet's South Pole."
"...we're in the middle of scorching desert under a blazing sun...check your navigation again."

"... never mind your map skills, what about your compass skills?"

[taalismn]

"... never mind your map skills, what about your compass skills?"

"Compass exploded about three hours ago."
"...And we're just hearing about this NOW?!"