Unusual Planets

>why would it collapse?
Because of intense gravity you dumb shit.

The only reason STARS don't collapse in on themselves is because they are incredibly large fusion reactors. As soon as the fusion slows down, so does the star.

>My mistake, it'd probably have no gravity at all.
Of course it will have gravity.
It's build around the fucking SUN.

Or it is a bubble on the inside of solid matter around a solar body.

which is what mine was - there were several shells around it (the elemental planes, specifically) but otherwise it was a bubble off space in a massive siolid mass around a sun. The sun waned over the course of an hour into a single star, and expanded 11 hours later into a full sized sun (12 hour days). There was no moon.

The entire thing was inhabited by hundred of races and their varients, each 'owned' by the Elder Wyrm dragon within whose territory they lived. The Wyrms crafted and bred and played with their races, and played the Great Game with one another using adventurers as pawns and tools. Spelljammers could take you anywhere within the sphere - they were typically crewed by the smaller races, and owned by shipping magnate families whose influence spanned the entirety of the sphere.

Aberrations lived in the spaces between the sun-star and the surface; they were alien horrors.

Dude, it has more mass than an entire solar system. It's guaranteed that it has gravity.

>I have never understood how a Dyson Sphere is supposed to work. Rings are easy. You just spin them.

A dyson sphere is literally a shell around a star. It's kept inflated by the radiation pressure from the star.
Liveable surfaces can be created with gravity generators; you've got plenty of power available, after all.
The Ringworld is a slice taken out of a dyson sphere, designed for maximum habitable area with a minimum of maintenance. It's spun for gravity effects, with bussard ramjets on the walls adjusting it's orbit, alongside the web of superconductor in the ring's floor that pushes against the star with a magnetic field, and can also use solar flares to deflect stuff.

My setting's world has a mars-like planet for a moon, sharing an orbit kinda like Pluto-Charon

There's also a hot neptune with a ridiculously eccentric orbit between the world and its star, that every few hundred years it causes a total eclipse for a couple days.

I'd guess because it's build out of some materiel that can withstand the compression
like how the top of a igloo is held up. but in sphere form.
fuck knows how you get it build tho,
borderline magic scaffolding?

Why don't you make a partially constructed Dyson Swarm and then use the energy to create artificial proton-size black holes to power your entire civilisation? It sounds more reasonable than building a full Dyson Sphere.

>like how the top of a igloo is held up. but in sphere form.
Have you ever tried building a bridge around the entire world without any support pillars?

It's inflated by the sun. All that light and radiation? It's pressure. It's basically a balloon.
You build it far out enough that the force of inflation counteracts gravity.

It's also painfully obvious that neither of you two know a goddamn thing about physics.

this is a good question
if I've got a giant solid ball I'm pulled on to the outside
if I dig down the gravity gets weaker till the at the middle it's (almost?) non existent

but if I hollow the middle out so It's a giant hollow ball, I'm (loosely?) pulled onto the outside
but if I step inside assumedly the gravity is only as strong as the balls wall is thick?

>It's also painfully obvious that neither of you two know a goddamn thing about physics.
Which would explain why I am asking a question.
It's not my fault I have to repeat the question several times because people only give dumb answers.

Flat world inside a giant "glass" sphere in a gigantic star-metal array, which connects to a few other specialized worlds (other planes). The entire system is contained within a larger sphere, which rests on the tips of the universal enforcer's fingers.

yes, I am of course a wizard

I'm sorry Grand Archphysicist, We're not worthy!

>yes, I am of course a wizard
Igloos are smaller than Earth.
Earth on the other hand is smaller than the sun.

I meant that, unless you make the shell as thick as a planet (which will come with its own problems), then you'd probably be far out enough that you'd just orbit the sun, not get pulled down directly into it. Of course, that depends on how close to the sun the shell is

>Igloos are smaller than Earth.
Dam! That's where I've been going wrong.
You know that would explain those adventures complaining about eternal night...

or I guess you could go reread
paying attention to the bit about
>borderline magic scaffolding

I mean once build, it'd hold itself up.

what animeme is this from

Valvrave. Don't watch it.
It's a typical Sunrise plot-twist mecha show.

>you'd just orbit the sun,
No, that's with a Dyson Ring.
When you rotate a sphere, most points on that sphere do not rotate around the middle, therefore you cannot employ rotation to cancel out gravity.

>people only give dumb answers.
You got the right answer twice now, dimwit.
But let me explain it simply, so you can understand it:
STAR THROWS OUT FAST STUFF
FAST STUFF HITS SOLID STUFF
FAST STUFF PUSH SOLID STUFF
SOLID STUFF NOT FALL IN

>You got the right answer twice now, dimwit.
Have you seen me repeat the question since?

Are you stupid?

Yes, I have.

And no. You seem to be, though.
Ah, the wonders of the american 'education' system.

>Yes, I have.
Then you seem to be suffering from delusions.
I suggest talking to a doctor about this.

Nothing to terribly absurd.

A hollowed out moon powered by a scientist turned god wizard who sits in a tower at the center of it acting as the "sun" for this world.

The inside has two layers with the upper layer being the main living area and the lower layer being a massive sewer system that circulates water and maintains other environmental systems.

Raw materials are brought in from the outside from mining asteroids and trade from the mainworld.

People are typically kept ignorant of a world out outside of the moon world except the trusted nobility and clergy who are allowed to move in and out for purposes of maintaining resources and trade.

A planet trapped in the interior of an artificial Black Hole. A million of years ago, the Precursors were attacked by an ancient Enemy. With the planet surrounded, the Enemy released a shell of light with enough energy so that it would form a 1-light-second sized black hole on the Precursor's Homeworld. The Precursors saved themselves and their planet from collapsing into a singularity by building a perfect-reflecting sphere around the planet. Unfortunately, they couldn't escape from being trapped, and the energy released in that ancient war is still with them within the artificial black hole, just outside the old Crystal Sphere. Ancients machines still harvest the energy from that trapped light thousands of years after the Precursors either found a way to escape or became extinct.

Two words:
Alderson disk

The problem is that even if you make your setting on a dyson sphere, where's the light going to come from? Sure, you can handwaive gravity by making it big enough, but you're still stuck without sunlight.

A planet orbiting a quasar. No star is needed.

Because the original concent was nver a solid shell. The original idea of a Dyson Sphere was a swarm of satelites and stuff orbiting the sun and collecting energy. The solid shell thing is sci-fi author's take on the concept

Matrioshka Brain.

>where's the light going to come from?

You don't live on the outside of the sphere, so the light comes from your very own contained star.
The point of a dyson sphere is power and stealth. The star vanishes from view, so your system can't be seen. You also have the entire power output of that star at your disposal.

That's why a ringworld is a compromise. You can still see the stars and access them fairly easily.

My fantasy world has a 575 day calendar based on the cycles and alignment of two moons (the planet actually goes around its star twice in that time and each of the typical seasons happens twice).

My best would pry be the one I made based off the five light layers of the ocean, but turned sideways. As single, lonely mountain is the only source of natural light on the entire planet. As light emits out over the world it only reaches so far. It essentially broke the world into Light, Twilight, Night, and the Abyss. Also the Hades realm, but life can only exist in the lighted parts, right? Surely nothing could be beyond the void wall...

Damn, I should really revisit this idea. My players loved it and it might be a fun exercise to expand the worldbuilding.

...

Played a game set in the netstorm universe once. It's basically a planet that was ripped up by the Furies, titans of storms. Huge amounts of cloud cover shield the surface, and life goes on above it on tiny floating islands that war against one another, each trying to sacrifice the enemy priest to their own god for knowledge and power.

Ended when our priest (of Thunder) drop-kicked the Thunder Fury in the balls. Less effective than imagined, because Thunder is kilometres tall, and all, and pissing off what amounts to God is a poor life choice.

Sounds cool

Valverave.

It's shit.

Not sure if any here noticed my friend posting the homebrew system "First Light" a year or so ago. In it, players are gods and can mess around with the world. We've used it to create settings we would later play D&D in.

Anyway, during one of the test campaigns I DM'd, I surprised the new godlings by having them wake up in a generation ship (pic related) out in deep space.

It turned out they were the ship's power source given sentience by an accident

What about the massive amounts of radiation?

Wizards.

I've thought of building a toroidal (donut) world after reading this article, but never took the jump since my knowledge of climatology isn't the best. Love the idea of a civilized world rising on a planet with 2-4 hour days. I imagine mapping that would be a bitch as well.

io9.gizmodo.com/what-would-the-earth-be-like-if-it-was-the-shape-of-a-d-1515700296

If you have a uniform spherical shell, the gravity inside of it (from the shell) cancels out completely. If you're inside the shell, you should get a bit of attraction from the layers closer to the centre, but that'd be it.

A phoenix world. Destroyed by its sun's supernova, and born again thanks to the very same materials that the supernova left on its path of destruction. All that it is left of the sun is a neutron star, one of the most radioactives and dense objects in the universe. Because it was reborn after the supernova, the planet is now made of extreme heavy and rare materials.

The alien civilisation greedily mine the resources from the system. They also use it as a gulag for the undesirables.

It's still ongoing in the game, but the world is slowly, thanks to the PCs fucking up big time, undergoing an erratic transformation into a divine/corporeal plane. They're recreating the ecology of Heaven, and thankfully for the poor dumb bastards, that's a net positive even if it roughfucks with spacetime something fierce. At least the sun is safe. For now.

In the brother Strugatski sci-fi book "Inhabited Island", people on a planet thought they were living inside the planet with sun at it's center. They were referring to their homeworld as "inside out".

Reason behind this was weird atmosphere which created optical illusion. Like when you look at the ship swimming into the distance, it would go higher the further it went until it dissappeared amongst the clouds.

haven't run it yet, but one setting idea I have been working on recently was for it to be set inside an O'Neill Cylinder(en.wikipedia.org/wiki/O'Neill_cylinder), magic would exist, but it requires either advanced technology(either external or implanted), and/or certain genetic modifications and specially designed organs to manipulate, with the aid of certain external entities making it easier(various AI's and Machines that by this point are considered gods and spirits and other ephemeral beings by the Cylinder's inhabitants), and the various races and creatures onboard the Cylinder besides "standard" Humans mostly being genetically modified from a relatively small pool of terrestrial life that was brought onto the Cylinder when it was forged long ago(mostly various species of livestock, pets, and vermin, not to mention Humans themselves often being used as the basis for creatures being forged)

overall it kinda has a Jack Kirby meets Dougal Dixon meets Mike Mignola kind of vibe, at least how I'm seeing it

another idea I've had was one based on this insane but fascinating book called Cosmos In Collision; amazon.com/gp/product/B00C4MF8UE/

to quote it's Amazon page;

Take a journey into a darkened age before time began.

Contrary to the perceived wisdom of modern science, the ancients tell us Earth began life as a satellite of the planet Saturn long before the appearance of the Sun, moon and stars. This was Earth’s purple dawn of creation, a twilight dreamtime stretching back into an ageless past before the light of day entered the world. Here, amongst mankind’s oldest memories, is a long-lost era in which our ancient ancestors battled for survival in a semi-nocturnal world devoid of any ability to mark the passage of time.

Why do the ancients insist Saturn was our first and best sun?
Why does world mythology always place the planet Saturn and the abode of the gods at Earth’s celestial north where the Pole Star is today?
Why do ancient texts speak of an age of darkness existing long before a fabled Golden Age when Saturn ruled the heavens in splendid brilliance?
. . . And, most intriguingly. . .
Why were humans seemingly so ill adapted for this primordial Age of Darkness, when the nocturnal flourished and survival of the fittest took on an entirely new and sinister meaning?

Cosmos in Collision answers these and other questions as to what life was like on a primeval Earth trapped for millennia beneath a volatile sub-brown dwarf star called Saturn. It then presents evidence for the existence of a former world, other than Earth, which may hold the key to mankind’s ultimate origins; a world close enough for humanity to study, explore and eventually colonize within a generation.

>Current planetary system has the shape of an atom
>the sun is hollow and produces vital force which is also light
>the moon is an huge geode and infuses the world's oceans with magic through the tides
>one of the "planets" is a ring made of air and huge spacewhales which agreggate particles and became living islands.
>gravity is proportional to the density of an celestial object's soul, so main planet and living islands work like Earth, but in the vulcanic and crustless planet is as light as the moon.
>Other "planet" is an ocean ring made from an inner whip-like core which atracts water around it and is separated from space by a gel-like transparent skin with a thicknes measured in dozens of meters.

Had a pretty cool terrestrial planet rotating on its side. One heat-blasted desert side, one cold side with a chemosynthetic biosphere. Lots of bioluminescence. Human colonists occupied a "twilight belt" just outside direct sunlight, and ventured onto the dark side for resources.

i found this interesting article on torus shaped planet: aleph.se/andart/archives/2014/02/torusearth.html

When most people talk about dyson spheres, what they actually mean is a dyson shell - being a rigid spherical structure encasing a star. As user here says a dyson shell isn't intended to be habitable, but the real problem with a rigid structure is what's known a the Shell Theorem.

en.wikipedia.org/wiki/Shell_theorem

>If the body is a spherically symmetric shell (i.e., a hollow ball), no net gravitational force is exerted by the shell on any object inside, regardless of the object's location within the shell.

Ergo a star encased by a rigid dyson shell would tend to drift due to minor perturbations in momentum and gravitation, and in the absence of active stabilisation by the sphere would soon collide with it. Another hurdle is that a rigid shell would have to withstand enormous compressive pressure - far in excess of any known materials.

A "dyson sphere" is actually a larger class of hypothetical megastructures intended to capture as much of a star's energy output as possible. A much more reasonable configuration is what's known as a dyson swarm, which is a collection of satellites all independently orbiting the star. Orbital mechanics make it difficult to get 100% coverage without overlap, but there are some configurations like the "snailshell" (pic related) that get pretty close.

The third type is what's known as a dyson bubble, which is like the swarm except it uses what are called "statites" - instead of being in orbit of the star, a statite is held in place against the star's gravity by radiation pressure. With enough of them you can get a non-rigid equivalent of a dyson shell that, without the drawbacks of compressive pressure or shell theorem drift. The practicality of the bubble approach is questionable with our current understanding of materials science, but can't yet be ruled out - in other words, more questionable than a swarm, but less questionable than the shell.

>>gravity is proportional to the density of an celestial object's soul,
So what happens if a wizard gets too powerful?
Do they have to depart Earth and become planets themselves?

So far, no wizard has ever become close to that. Only the celestial dragons did.

And mages tend to acquire power in the way of manipulating mana, which is not the same as prana, the atual soulstuff.

So this is what every RPG world from before 2001 looked like.

when deep liquid borne species build megastructures for habitation