D&D General Campaign setting in a Gas Giant World with Floating Islands

Kobold Avenger

Legend

• Sep 17, 2021

• #1

I'm pondering a world that's a "Gas Giant" possibly even the size of Jupiter, but not like a real one that would be toxic and very deadly. But one where it's quite livable to be in and most of the people live on floating islands or earth motes of various sizes. And that the main method of getting around is Airships. Also I want to technology of most places around the world to between the equivalents of the 1600's to early 1800's, roughly what covers the Age of Piracy and a little beyond. I definitely want Airships to be using cannons (both non-magical with cannonballs and magical with elemental energy varieties) against each other. Yes there probably will be a lot of sky pirates.

So here's some things I'm pondering, what happens if someone falls off an island or a ship? Should there be a bunch of additional last chances, before falling into unknown oblivion of whatever might be at the planet's mysterious core or lower atmosphere?

A planet the size of Jupiter is much larger than most of us can fathom, so what sort of supernatural phenomena should there be to make travel around the world quicker? Air their magical currents of wind that Airships use? In fact how long should it take for an airship to go around the world?

What creatures live in the skies that compose most of the world?

 

log in or register to remove this ad

Oofta

Legend

• Sep 17, 2021

• #2

Below the islands there is thick matted structure known only as "The Tangle". A layer of bramble and thorn that forms a sphere around the most inner portions of the planet. It is possible to fall through The Tangle, whether getting caught or not is a better fate is often debated. Things live in the tangle living off the dead creatures that live above and anything else that falls. No light penetrates this layer, in many ways it's the equivalent of the underdark.

There are giant earth sized storms (think Jupiter's red spot) that people can ride the fringe of to go great speeds. The closer to the center, the faster you go. At greater risk of course. There are also bands and eddies like the stripes of Jupiter. Or perhaps there's just large sections of the world that are unexplored.

Things that live in the upper layers of the world mostly look like ocean creatures. Flying behemoth whales, soaring manta rays and so on.

 

Yaarel

He Mage

• Sep 17, 2021

• #3

I am unsure of the astrophysics here. Are these floating islands sorta like "moons" or a "ring" of debris that exists within the gaseous atmosphere?

 

Bill Zebub

“It’s probably Matt Mercer’s fault.”

• Sep 17, 2021

• #4

Carl Sagan once theorized about what life might look like if it existed "on" ("in"?) Jupiter. I think it involved enormous creatures that "swam" in the gas clouds.

The first question to ask is how these islands "float". If the answer is that the gas is so dense that they float normally, then you've just got a normal island/water world but with something other than water. Which isn't terribly interesting.

So assuming that it's actual gas, and that you have some mechanism by which the islands float, I see two potentially interesting differences between this and a more typical island world:

1. 3D. Not only do the ships travel in 3 dimensions, but the islands themselves won't necessarily all be at the same altitude. What determines the altitude of a given island, and does that altitude have any implications for status/trade/etc.? Are some strata better for travel/trade, but others have more pleasant climate? Maybe the calm ones are good for airships, but the stormy ones are good for growing crops? Are there strata perpetually enshrouded in thick clouds, where "bad guys" like to hide?

2. Movement. Do the floating islands change position relative to each other? What are the implications for political structure and alliances?

 

Yaarel

He Mage

• Sep 17, 2021

• #5

Is the gaseous atmosphere generally transparent like Earth air, or foggy? If transparent, the core might be seen plainly and nonmysterious.

If one fell, one would fall thru the core to toward the other side of the planet, until gravity pulled one back, and they would bounce back and forth until air friction stabilized them somewhere in the core, where presumably they would orbit or drift with the rest of the air currents.

 

Bill Zebub

“It’s probably Matt Mercer’s fault.”

• Sep 17, 2021

• #6

By the way, slightly off topic but just two nights ago we got out a telescope and I showed by kids (ages 5 and 8) the moons of Jupiter for the first time. All four (of the major ones) were visible, and we talked about their names and what they are like. It was pretty magical for them. (We also looked at Saturn's rings and Titan.)

 

Yaarel

He Mage

• Sep 17, 2021

• #7

Here is an image of Neptune. Its blue color might be what a gas giant might look like with an earthlike atmosphere.

 

Yaarel

He Mage

• Sep 17, 2021

• #8

Looking at images of Saturn and Uranus, the surrounding rings seem discrete away from the gaseous planet. I am unsure if the rings can exist within the atmosphere of the planet. Perhaps they can where the atmosphere is thin and transparent, but not towards the core where the atmosphere is thick and translucent.

 

Yaarel

He Mage

• Sep 17, 2021

• #9

Interestingly, Neptune is thought to be an "ice giant" with windy icy atmosphere gradually merging into a boiling-hot liquid ocean around a rocky core.

 

Kobold Avenger

Legend

• Sep 17, 2021

• #10

Yaarel said:

I am unsure of the astrophysics here. Are these floating islands sorta like "moons" or a "ring" of debris that exists within the gaseous atmosphere?

Click to expand...

It might be a bit of both, I certainly see their being clusters or archipelagos of islands, but some islands could be continent sized, but no bigger than Australia.

Yaarel said:

Is the gaseous atmosphere generally transparent like Earth air, or foggy? If transparent, the core might be seen plainly and nonmysterious.

If one fell, one would fall thru the core to toward the other side of the planet, until gravity pulled one back, and they would bounce back and forth until air friction stabilized them somewhere in the core, where presumably they would orbit or drift with the rest of the air currents.

Click to expand...

The upper atmosphere is like Earth Air, but the lower atmosphere would be foggy. And if one fell to the core, who knows what happens? I see it as most don't survive to tell what's there.