Setting limits on the size of Roshar (the planet) and Roshar (the continent)

[Leiyan]

I expect the moons were put in their current orbits artificially, but by whom or what I do not know. On astronomical terms, these are not stable orbits, but astronomical terms means millions of years. A few thousand or even a few hundred thousand years are no problem.

 

Peter, any chance you could answer this question? 

 

Were the moons also artificially created, or were they originally formed naturally?

 

edit: typos ><

Edited February 27, 2014 by Leiyan

[PeterAhlstrom]

I don't know.

[Leiyan]

Thank you for replying! 

 

I've been trying to make some speculations about the moons, there is just so little to go on thus far.  I assumed they were natural until I came across your statement about artifical placement.  Very, very interesting....

[Xavien]

Deviating back to the dimensions discussion, drawing a straight line that goes coast to coast from Shinovar through the city of Shulin, but not including that jutting sliver of land, is approximately 3200-3300 Alethi "units"  I derived this using the scale provided on the map of Alethkar ( http://coppermind.net/w/images/Alethkar.jpg ).  From Varikev to Dumadari is ~1100 units. Using the map of Roshar which includes those cities (http://coppermind.net/w/images/Roshar.jpg) you can get an idea of the scale of 1100 units on the larger map.  Applying this to the width of Roshar then gives ~3200 units, but due to potential inaccuracies in either map it could be closer to 4000. 

 

I feel relatively good on the above, but it all comes down to map accuracy between the two, though simply saying that that width of Roshar is ~3x the distance from Varikev to Dumadari would be another way to put it and only have to worry about the accuracy of one map. The below is speculation based on a single reference.

 

Well, how big is a unit? From a reading of The Way of Kings (Nohadon version)

 

Those dear to me took fright for my safety and, perhaps, my sanity. Kings, they explained, do not walk like beggars for hundreds of miles.

 

Nohadon is very likely from Kholinar, where we see him talking to Dalinar in a vision. So there is a good chance that the Alethi work in miles.  If that is the scale of the Alethkar map, then Roshar has a width of ~3200-4000 miles or ~5000-6200 km.

 

That feels really small, particularly for a supercontinent. 3300 miles is about the distance from LA to NYC so the overall landmass would be less than that of the US. On the other hand that much empty ocean would certainly help high storm creation and such a "short" landmass would mean it would still be going strong by the time it hits the mountains around Shinovar.  

 

The Alethi mile could also be longer than ours.  I don't have my book on me so not sure how many "mile" reference there are, I just remembered the one and was able to look it up in the wiki.

Edited February 27, 2014 by Xavien

[GroundPetrel]

 

Deviating back to the dimensions discussion, drawing a straight line that goes coast to coast from Shinovar through the city of Shulin, but not including that jutting sliver of land, is approximately 3200-3300 Alethi "units"  I derived this using the scale provided on the map of Alethkar ( http://coppermind.net/w/images/Alethkar.jpg ).  From Varikev to Dumadari is ~1100 units. Using the map of Roshar which includes those cities (http://coppermind.net/w/images/Roshar.jpg) you can get an idea of the scale of 1100 units on the larger map.  Applying this to the width of Roshar then gives ~3200 units, but due to potential inaccuracies in either map it could be closer to 4000. 

 

I feel relatively good on the above, but it all comes down to map accuracy between the two, though simply saying that that width of Roshar is ~3x the distance from Varikev to Dumadari would be another way to put it and only have to worry about the accuracy of one map. The below is speculation based on a single reference.

 

Well, how big is a unit? From a reading of The Way of Kings (Nohadon version)

 

 

Nohadon is very likely from Kholinar, where we see him talking to Dalinar in a vision. So there is a good chance that the Alethi work in miles.  If that is the scale of the Alethkar map, then Roshar has a width of ~3200-4000 miles or ~5000-6200 km.

 

That feels really small, particularly for a supercontinent. 3300 miles is about the distance from LA to NYC so the overall landmass would be less than that of the US. On the other hand that much empty ocean would certainly help high storm creation and such a "short" landmass would mean it would still be going strong by the time it hits the mountains around Shinovar.  

 

The Alethi mile could also be longer than ours.  I don't have my book on me so not sure how many "mile" reference there are, I just remembered the one and was able to look it up in the wiki.

 

(responding to bolded text): What if that was up-and-down Roshar?  Or only a fraction of the way across it?  

 

I need to go find that quote and its context.  

 

Anyway, I got the impression that Roshar is both larger and less dense than Earth, possibly with slightly less atmospheric pressure.  That would explain the gravity, at least.  

 

I can tell I'm going to be spending a lot of time on the SA subforums.  Sel, Scadrial, and Nalthis are Earth-like enough to set aside, but the Rosharan system is AWESOME.  

[PorridgeBrick]

I believe Brandon said the air has more oxygen when he was explaining the sizes Chasmfiends can grow to. That either means the composition of the atmosphere is pretty different, or that atmospheric pressure is actually greater on Roshar.

[Swimmingly]

Or just that the photosynthetic process is more efficient, or other elements are absorbed to make the shells, or the highstorms/crem foster chemical actions trapping nitrogen, or...

[Eri]

Back to the moons, orbits and stuff:

Why do we assume that Roshar year is based on it's orbiting time? The seasons are so irregular and seem to have no correlation with orbital movement. The year is defined by the Weepings, which are indeed likely related to / caused by some astronomical phenomenon but I don't see why it has to be position on orbit. I'd rather bet on something like proximity to another planet (Braize?) or some kind of eclipse / conjunction / things like that.

 

Peter, could you please tell us if Roshar year = how long it takes to go rund the orbit? I mean, if Weeping always occurs when Roshar is on the same place on the orbit around its sun?

 

PS: I'll probably post something more on astronomy and climate after I finish another reread. I wonder what direction noon sun shines from, it's really not obvious here. And many other things related to planet tilt…

Edited March 1, 2014 by Eri

[Leiyan]

I think you saw this in the another thread, but Roshar has no tilt to its axes (http://lunarubato.tumblr.com/post/42954839930/ok-so-here-is-the-information-we-collected-from). Which means, the sun is always at the peak of its arc at noon, but not necassairly at the zentih.  In fact it would only be at the zenith on the equator.

 

Anyways, It was stated in the books that the Weepings happened at the end of every (Rosharn) year, like clockwork.

 

Kaladin hated the Weeping. It marked the end of an old year and the coming of a new one, four solid weeks of rain in a ceaseless cascade of sullen drops.

...

While other seasons of weather came and went unpredictably, the Weeping never failed to return at the same time each year.

-Chpt 44

 

 

I haven't even attempted to read any of the theories about the Weeping yet, so I shouldn't really speak about it... but, personally, due to my other orbital theories, I'm beginning to wonder if the Weepings occur when Roshar is at the point furthest from the sun (aphelion).  Obviously they would have to occur at the same point it Roshar's orbit every year, and aphelion makes as much sense to me as anything else!!

Edited March 2, 2014 by Leiyan

[Kurkistan]

A couple things I thought of but haven't had time to explore fully:

 

Stars. If we had stars that were visible in one place but not another or better yet differing angles above the horizon that would be a great help. Unfortunately there are very few mentions of stars in WoK and the only mention of a particular stellar feature that I could find is Taln's Scar, mentioned twice, but both times in Alethkar AFAICT. (There's also a mention of starspren, which could actually be planets or other small nearby objects)

 

Climate. If we could figure out a climate model for a planet with a single supercontinent we could get something from that. For example, seasons don't seem to follow the solar calendar, which indicates a small axial tilt. That probably means the poles would get very cold depending on how ocean currents flow(and absent large longitudinal continents like we have on Earth, I imagine they would travel more or less laterally.) With Rosharan climates being fairly consistently mild, this would mean that the continent probably occupies a small number of latitudes near the equator.

 

Highstorms. It is possible that highstorms are a sort of atmospheric "super-tide". We know that is has a complex periodic nature, which could be consistent with the interaction between three moons and the sun, especially if the moons are artificially placed to create a sort of resonance effect. It's not like we haven't seen large-scale resonance effects before on Roshar. It travels East-to-West, which I assume is the opposite direction of the planetary rotation. If we could figure out the resonance pattern then the frequency and speed of highstorms should give us a clue.

 

Though it might not clue us into size, I think you're correct that we should look at stars and seasons.

 

Forgive me if someone else mentioned this in the last hundred posts (), but I noticed something rather interesting in a recent reread of WoK:

 

Taln’s Scar—a swath of deep red stars that stood out vibrantly from the twinkling white ones—was high in the sky this season.

 

This season. Stars. With seasons being based on highstorms. This means that, unless Kaladin (our POV here) is a true deceiver and just means "this time of year", Roshar's topsy-turvy seasons are actually such that they affect the planet's orientation relative to the stars.

[-Deleted-]

First of all, congratulations on becoming a recent fan.  second, fantastic job on figuring out the gravity difference. Third, keep reading.

[Harakeke]

Apologies if this has already been mentioned, but in my search for glyphs to translate, I noticed that Navani's "Map of the Battle of the Tower" gives a scale in feet.  You could conceivably use this to measure the size of landmarks in the various maps, chaining upwards until you reach the full Southern Hemisphere map that shows all of Roshar. You'd have to deal with projection distortions, but georeferencing the maps first would take care of that. 

Edited March 7, 2014 by Harakeke

[Kurkistan]

What about your own translation of the Thaylen sea chart, Harakeke? Doesn't that have longitudinal markers that we could extrapolate from?

[Harakeke]

What about your own translation of the Thaylen sea chart, Harakeke? Doesn't that have longitudinal markers that we could extrapolate from?

 

Well, the distance between the degrees of latitude would depend entirely on the circumference of Roshar.

[arbron]

A couple of thoughts on this based on Words of Radiance and the speed of highstorms. First, WoR establishes that:

 

the highstorms [are] all one storm that rounded the planet

 

and

 

assuming [it] moved at the same speed as a highstorm this time of year, they'd have a few days before it returned

 

(both quotes from chapter 87, hardcover page 1049–1050).

 

I can't find the exact quote, but somewhere in the book I remember it saying that a highstorm takes about a day to travel across the continent of Roshar. Assuming that the storm travels at roughly the same speed on its way around the planet, it seems like this gives us a (very) rough idea of how big the continent is in relation to the whole planet.

[JamHeretic]

If it's at all helpful for calculations, Brandon gave us his rough guidelines to how far "a day's ride" is. See http://www.17thshard.com/forum/topic/6579-seattle-signing-report/

[Elbereth]

It was my understanding that they didn't actually know whether the highstorm was continual or constantly reforming.

[Oudeis]

I wonder if this topic might interest you? There's very little there you haven't written here, but perhaps it'll give you something to think about?

Also I still really wanna know what the thing is Peter says we've missed, and I wonder if it's the Highstorms.

[Zizoz]

I recall that somewhere in WoR the following distance is given:

The Shattered Plains are 400 miles from the ocean.

 

[Oudeis]

Not entirely relevant, but as I think someone's pointed out, the map has latitudes... I realize they don't actually help with distance, but it is worth noting that we can see latitude 0. Can Peter confirm or deny whether this is (at least approximately) the actual equator?

Edited March 17, 2014 by Outis

[sh3nahz]

i dont think you could accurately tell the size of Roshar by how long a character would take to walk. for instance on our planet as a species is quiet diverse due to environmental and genetics through time, like desert nomads being able to walk huge distances, or nepalese/himilayan mountain men being able to survive in high altitudes. The races of roshar would have similar genetic/environmental differences. Not to mention they might have differences in their DNA due to being created by shards, so although they may be human they probably arent exact analogues of earth humans. On Scadrial the nobels and ska were altered by rashek in many ways and the races on roshar look like they have many variations. although these could be muted by generations of interbreeding. that being said the distance a member of a race could walk maynot be accurate to get a viable measurement.

 

Plus im guessing that 4 month time length would be taking into account the cycle of highstorms . If it was during a weeping it may be able to travel further with better weather than during a frequent cycle. That being said as roshar is a super continent the amount of daylight/ night hours may hugely vary dependant on latitude and orbital axis to the sun  as well as seasonal differences. 

[Blightsong]

Brandon actually talked about whether there were other landmasses on Roshar before.

 

http://www.theoryland.com/intvmain.php?i=977#63

I also personally asked Brandon if Roshar was always the only large landmass on Roshar. I was told that it was, but that there was once no large landmass on Roshar at all. What does that mean for its density, and thus, Gravity?

[physicskid]

in words of radiance they specifically talk about the change in time zone between Urithiru and the shattered plains. This seems like it should allow us to calculate how many degrees of longitude they covered in the jump und give us a data point for the size of roshar relative to the planet.

[Kal]

I think we can use some references to climate as a guide. Obviously the Frostlands are very cold, and Tozbek tells Shallan that far to the south, the ocean freezes. Sea ice extent on Earth has been changing, but I think the Arctic and Antarctic Circles are good baselines. Then consider the countries to the far north. Iri is said to be very warm, as are the Reshi Isles. Northeast of the continent is the Steamwater Ocean. Based on these climatic references, I would guess that Thaylenah straddles the 55 parallel and the Reshi Isles lie somewhere between Roshar's equivalent of the Tropic of Capricorn and its equator.

 

Using these constraints, I added the color map of Roshar from WoR as an image overlay in Google Earth. I resized the image to these constraints, maintaining the aspect ratio of the image. This is definitely not ideal georeferencing, but without more data points, I think this is pretty good.

 

Now, assuming the circumference of Roshar is indeed 70% that of Earth's, as has been calculated, then a simple measurement and calculation reveal Roshar to be approximately 6300 km from the mountains west of Shinovar to the northern-most of the Unclaimed Hills.

 

Additionally, using the map of Alethkar as a reference the Sea of Storms measures about 400 km, meaning 3 Roshar units are equal to 4 kilometers.

 

EDIT:

I missed the fact that there are degrees of latitude labeled on the B&W map of Roshar. Using those and a measurement (just on the map, not on GE) of the Sea of Storms means that 1 degree on Roshar is roughly equal to 290 Alethi units.

 

Also, I realize I made a mistake in my earlier calculations. I based them on Roshar's circumference being 70% of Earth's, but it's actually it's radius that is 70%. If Roshar's radius is actually 70% of Earth's, then 1 degree on Roshar is ~80 km. Simple conversion of kilometers to Alethi units...1 km = 3.6 Alethi units.

 

The northern coast of Herdaz sits at about 13° S and the southern coast of Thaylenah sits at about 67° S, so there are about 54° between them, or ~15,660 Alethi units, or ~4,320 km.

Edited November 2, 2015 by Kal

[Argent]

A bit of a necro, but I was going over the February 2016 tweets, and it looks like @DeathIsSilver on Twitter got "Roughly 4000 miles East to West" from Isaac on the size of the Roshar supercontinent. Which may have changed, as per Peter's "globe experiment."