Smaller Planets

[Someone]

Would it have an effect of weather? Weather patterns are affected by the Coriolis efect, and that depends on speed of rotation. I can't make if the planet size would have an effect on that and how big that would be.

Edit: I forgot that smaller planets cool sooner than bigger planets, and thus probably lack active volcanoes and moving plates. One possible solution is having a very active heat source, like a core with a large amount or radioactive elements. Since many of them are also very dense, that could help with the gravity problem, too. Assuming you want the smaller planet to work like ours.

 

[Cheiromancer]

The density of gold is 19.3 times that of water. The density of our earth is 5.5 that of water. Lead is only 11.3 times that of water, and iron is 7.8. That's at room temperatures; if molten and under extreme pressures it wouldn't be much different, I'd think. So if a substantial component of the core were gold (instead of iron, like our planet's core) then you'd easily make the doubled average density. No need for fantasy materials like adamantine.

Uranium is also very dense; 19.1 times that of water. A little more uranium than earth would help keep the core nice and hot, and ensure volcanic activity. More importantly, a molten core is necessary for strong magnetic fields that protect against solar wind. Without this protection your atmosphere gets stripped away.

 

[hong]

The density of gold is 19.3 times that of water. The density of our earth is 5.5 that of water. Lead is only 11.3 times that of water, and iron is 7.8. That's at room temperatures; if molten and under extreme pressures it wouldn't be much different, I'd think. So if a substantial component of the core were gold (instead of iron, like our planet's core) then you'd easily make the doubled average density.

So THAT'S where all the gold in dungeons comes from....

 

[Michael Morris]

Carthasana is a world in orbit around a binary star pair - but maybe once every 3rd session or so do I actually remind players of that, usually when they ask for time around dusk or dawn. There are three moons as well and a red nebula in the winter sky but that rarely ever actually matters to the game.

A planet's size will affect the players even less since they can't grasp it. Remember that up until 500 years ago most people thought the world was flat.

 

[Umbran]

In a large part, the issue of gravity doesn't have to be "solved" at all. Creatures could evolve or be created for their environment - effectively, for the character's point of view, everything is relative. On a lighter world you have a person with a smaller frame and less robust musculature, and he can still jump what he'd call "10 feet", and still lift "150 pounds". Unless the character also interacts with an Earth-like world, there's not much that needs to be done. He can still have earthlike seasons, and a relatively large Moon, and so on.

Yes, technically a much lighter world would have problems holding an atmosphere, in the long term. It isn't as if the characters are going to notice that discrepancy.

 

[sckeener]

Wouldn't the seasons be more dramatic in a smaller world? I guess it would depend on how much energy that is assaulting the planet, but I'd think that it would take less energy to cause sweeping changes.

 

[hong]

Wouldn't the seasons be more dramatic in a smaller world? I guess it would depend on how much energy that is assaulting the planet, but I'd think that it would take less energy to cause sweeping changes.

Seasons are a function of axial tilt. The more extreme the tilt, the more varied the seasons.

 

[Cheiromancer]

Seasons are a function of axial tilt. The more extreme the tilt, the more varied the seasons.

And length of year. If the planet orbited around the sun in only a month, there wouldn't be much time for the differing length of the days to make much of a difference. And similarly for a long year.

As far as size of the planet goes, I'd think a smaller planet would have less extreme seasons. Cold air would have less distance to travel to meet warm air. Think of an extreme case where a planet is only a few miles across; a breeze would mix all the polar air with the equatorial air and there would be little difference in temperature. This assumes that air pressure and gravity are about the same, and so the atmosphere is about as thick as it is on earth.

I don't think the different heat capacity of the ocean would make a difference. Sure the oceans are all smaller, and so are capable of storing less heat, but I think it is heat capacity per unit area which is important. And that would be about the same.

 

[Mercule]

The density of gold is 19.3 times that of water.
...
Uranium is also very dense; 19.1 times that of water.

Uranium is lighter than gold? Interesting.

No need for fantasy materials like adamantine.

I say screw fantasy materials. Put a portal to the plane of Fire, Earth, or the Abyss in the center of the planet. Bind the planet together with weaves of magic (think very big mage armor, inverted). Then, make the thing a hotbed of geologic activity, since the planet is pretty much a very small cork to a very large bottle (works best with creamy Abyssal filling).

Now, that would be an interesting world on which to play.

 

[Nifft]

Go here .

That site is a lot of fun. Thanks! -- N