Ashfalls

[Andrew the Great]

Vintage, in reference to your questions about climate, the reason our poles change so little throughout the year is because the get about the same amount of sunlight each day all year. If the planet were to be tilted sideways, though, the the rotation of the planet would be weird, yes, but the poles would have a season where they were facing the sun and one where they were facing away. This would be extreme climate changes, so it's probably not quite that extreme, but something along those general lines is what we're going for, I think.

On a side not, thanks to whoever pointed that out about the poles, I totally missed that.

[AvalonDreamer]

Very muchly, thank you for pointing it out. I missed a lot at the end of WoA out of sheer excitement.

As an extension of Andrew's explanation - Poles are often interchanged with the concept of a planet's axis (ours are very close) , but they really aren't the same. The poles of a planet are merely where the magnetic fields are strongest, except right atop the pole, where it disappears entirely.

Actually that just gave me an idea... What if the Deepness is weakened or repelled somehow by the stronger magnetic field at the poles, and realizing this, Preservation (or TLR, with it's help) created allomancy as a weapon against it? That would further support my theory about the mists not attacking allomancers, and why Vin could use them as power (if of course, the mists are Preservation's doing).

[Czanos]

So it appears that the lands surrounding this patch of life at the poles are very hot most if not all the year round. When Sazed returns to Luthadel in Well of Ascension and talks with Tindwyl about his duty, she calls them the burnlands.

". . . You are supposed to be in the Eastern Dominance, teaching the people on the borders of the burnlands.

So basically we have life at the poles of this planet surrounded by vast burning deserts. (I think Vin mentions the deserts when in the Well as well.) The ashmounts almost for sure have something to do with this, as they generate a layer of ash around the planet so thick the sun is the only thing that seeps through. Stars can be seen with Allomancy, but only on very clear nights.

I also like the idea of the deepness being repelled by the strong magnetic forces of the planet's poles. After all, when the mist killings happen, they happen from the fringes of the empire towards the center, lending credence to that theory. Not so sure about Preservation making Allomancy though. I'm guessing just when the Lord Ruler got the power at the Well, he knew that the poles were safer from the deepness and remade the world to make those areas livable. (By creating the ashmounts in a roughly circular pattern to keep the area as clear as possible.)

[Qarlin]

How would the Ashmounts keep away the Deepness? They seem to only blot out the sun, so unless the sun was changing to a red giant or going nova or something, then they don't seem to make much of a difference. Also, since the death of TLR they've started getting more active, and later, if I understand correctly, start causing earthquakes and all that rot. So what if they're actually part of the Deepness? Like it's a destruction from the depths of the earth. Something.

[AvalonDreamer]

I see where czanos was going with the Ashmount thing, I think. What if they were there to keep people in the safe region of the world? Then, they'd be kept just a little active to keep the weather liveable...

[darxbane]

The poles of a planet are described in two ways, the magnetic poles and the axis poles.  The axis poles represent the points where the planet spins on its axis.  The magnetic poles do change periodically.  In fact, the current center of a Northern pole is allegedly somewhere in northern Siberia right now. 

Anyway, I am re-reading MB1, and found that the Central Dominance has very mild winters.  It rarely snows there.

[AvalonDreamer]

From what I've read (like 5 years ago... And we've seen how well my memory works...) magenetic poles do drift, but only very slightly; when they actually change, it happens fairly rapidly (over a period of a few years). Then again, that was pertaining to Earth...

As for the Axial poles being referred to as 'poles' thats a DVD thing all over again.

[Peter Ahlstrom]

Axial poles are more common in astrophysical bodies than magnetic poles. Many planets and other planetlike objects in our solar system don't have a substantial magnetic field.

Do we have any indication in Mistborn that people know what a magnetic pole even is? I don't remember any compasses.

[Qarlin]

Point!

And while the pushing and pulling could be related to magnetics, it's prolly only in appearance, and just barely at that. But how would they decide north without some form of decided compass? What makes the Northern Dominance the northern one if they didn't have any idea what compasses or magnetic poles were? No stars to guide by.

[Peter Ahlstrom]

The sun travels across the south part of the sky, so opposite the sun at noon is north. (And yes, if you're in the southern hemisphere the sun moves across the north part of the sky, but it still rises in the East and sets in the West (unless, perhaps, you are on a planet with retrograde rotation).)

[SarahG]

The sun travels across the south part of the sky, so opposite the sun at noon is north. (And yes, if you're in the southern hemisphere the sun moves across the north part of the sky, but it still rises in the East and sets in the West (unless, perhaps, you are on a planet with retrograde rotation).)

What do you mean by "retrograde rotation"?  If the planet spins the opposite way, wouldn't that just make the opposite pole the north one?

[Peter Ahlstrom]

There are two schools of thought on that. (See here.)

The IAU says that the north pole of a planet is the one that is above the plane of the solar system, and if the planet rotates backwards it has a negative rotation and the sun rises in the west. Axial tilts can't be greater than 90 under this system.

Another school of thought is that if the planet rotates backward, the axial tilt is greater than 90 and the sun still rises in the East and the north pole is the one below the plane of the solar system.

(See also here.)

[SarahG]

Thanks, Ookla, that was an interesting tidbit of astronomy that I was not only ignorant of, but had never thought to wonder about before.  I still think that first school of thought is rather Earth-centric, though; with my current level of astronomical knowledge I'd be inclined to vote with the second school of thought.

That reminds me about something that bugged me in Elantris.  (I know, I'm getting off-topic.  Feel free to reprimand me.)  Isn't Kae to the east of Elantris?  And doesn't Raoden in the first chapter see Elantris's shadow looming over Kae as the sun rises?  I would think maybe this was one of those retrograde rotational planets, except I'm pretty sure there are other references in the book to the sun rising in the east, setting in the west.  Thoughts, anyone?

[Peter Ahlstrom]

I don't have an answer to the second question, but as for the first one, it's not as Earth-centric as you think.

All the planets in the solar system revolve around the Sun in the same direction. Most of them also rotate in the same direction that they revolve in, and anything else (like Venus and Uranus) has retrograde rotation. You determine which side of the solar plane is north by using the "right-hand rule"...hold up your right hand with the fingers curling out and the thumb pointing upward. The thumb represents the vertical axis of the sun & all the revolving planets, and the curl of the fingers represents the rotation of the solar disc (the direction the planets move). Thumb points to "north."

If you find a solar system whose planets go the other way around the sun, that's when you flip your spaceship upside-down and call up "north." So in that way it's not an Earth-centric definition. (Though of course ultimately how they decided on counterclockwise instead of clockwise is because that's the way the Earth is, so that's Earth-centric, and more specifically, northern-hemisphere-specific...)

[Qarlin]

Okay, I think that works.