Effect of axial tilt on a planet

[GuardianLurker]

Boring.

Minimal weather patterns, pretty much the whole planet would have an even day-night cycle. Take out the moon and you don't even have to worry about tides and volcanos. So, this is the option you'd go with if you want an excuse not to worry about any of those things.

You *don't* want to take out the moon. The moon is what keeps the earth's tilt/rotation stable; it essentially transforms the Earth/Moon system into a gyroscope. Without the moon, the axial tilt varies wildly (like Mars') and the formation/continuation of life is very hard if not impossible.

 

[GuardianLurker]

Are you sure? It sounds strange .. I thought that the tilt is the main reason for seasons. Wikipedia agrees.

Wikipedia isn't always right; after all, it's drawn from the same kind of knowledge base exhibited here.

Seasons are determined by two things: distance-to-sun and length-of-day. Eccentricity controls the first. Obliquity controls the second. Earth's tilt is severe enough, and eccentricity small enough, that Obliquity is the primary factor.

But in a fictional world, those could easily be inverted.

 

[Someone]

Seasons are caused by the eccentricity of the planet's orbit.

If that were true, both hemispheres of a planet would have the same season at the same time, and we know that this isn´t true.

 

[BiggusGeekus]

You *don't* want to take out the moon. The moon is what keeps the earth's tilt/rotation stable; it essentially transforms the Earth/Moon system into a gyroscope. Without the moon, the axial tilt varies wildly (like Mars') and the formation/continuation of life is very hard if not impossible.

I did not know that. Thanks!

 

[jgsugden]

Uhhhhhh ... maybe I'm missing the point, but this is a fantasy game. If you want long seasons, have long seasons. If you want flash floods every few weeks, add those too. If you want the occasional rain of toads, then let the fribbit fly. You don't have to belabor all the explanations.

If you try to focus on all the scientific details, you'll just disappoint yourself. At some point, everything breaks down because the rules of the game, and the beings that populate your games, do not use real world statistical models as backdrops. At some point, the collision between your efforts towards a 'real' world and the inherent fantasy of the setting will collide and you'll be forced to accept the simplificatios and fantasy.

If you do end up with one of those players that asks, "Hey, why does winter last so long?", just tell him, "Because the Gods will it." That solves most of these problems.

 

[Desdichado]

Boring.

Minimal weather patterns, pretty much the whole planet would have an even day-night cycle. Take out the moon and you don't even have to worry about tides and volcanos. So, this is the option you'd go with if you want an excuse not to worry about any of those things.

Yes, but take out the moon and you no longer have any stabilizing effect to keep the world at that no axial tilt, so it would probably go through long-lasting gyrations where the axial tilt swung from one extreme to another.

 

[Miln]

Yes, but take out the moon and you no longer have any stabilizing effect to keep the world at that no axial tilt, so it would probably go through long-lasting gyrations where the axial tilt swung from one extreme to another.

Would rings have the same stabilizing affect?

 

[Janx]

According to my old college astronomy book:

Length of day is determined primarily by planetary rotation. Venus' day is actually longer than its year.

Then why are the days and nights longer in Alaska than in Texas? It's partly based on their location from their equator to the pole and the TILT of the earth. The tilt would affect the length of time that location is exposed to the sun.

Janx

 

[Desdichado]

Uhhhhhh ... maybe I'm missing the point, but this is a fantasy game. If you want long seasons, have long seasons. If you want flash floods every few weeks, add those too. If you want the occasional rain of toads, then let the fribbit fly. You don't have to belabor all the explanations.

Who said it's a fantasy game? I made no reference whatsoever to my game, and since I'm asking scientific questions, your assumption that it's a strictly fantasy game seems at best misplaced.

If you try to focus on all the scientific details, you'll just disappoint yourself. At some point, everything breaks down because the rules of the game, and the beings that populate your games, do not use real world statistical models as backdrops. At some point, the collision between your efforts towards a 'real' world and the inherent fantasy of the setting will collide and you'll be forced to accept the simplificatios and fantasy.

Again, what inherent fantasy? You don't know anything about my setting; why would you assume that?

 

[Desdichado]

Would rings have the same stabilizing affect?

Probably not; the mass of rings is minimal compared to a good moon -- our moon is roughly 25% of the mass of the Earth. Rings can vary from the ephemeral structures around Jupiter to something more like the magnificent structures of Saturn, but in any case, they'd likely be a fraction of 1% of the mass of the host planet.

Rings are cool, though. Imagine the mythology of a world that has a ever-present, unmoving series of big silver bands that go across the entire sky, visible day or night.