(11-05-2024, 11:57 PM)Isodecan Wrote: I tend to assume that the maps of Remnant we see cover at most a quarter and more likely closer to an eighth of the actual world of Remnant given that Atlas is unquestionably in a polar location whereas Menagerie seems to be closer to the equator.
Actually I decided to work out the math, rather than think about The Thing tonight:
Looking at this map, there's really one easy thing that we can do here, which is to place the deserts at something like the correct geography. If you have a rotating planet, you are going to get excess heat in the tropics and cooling at the poles, and thus physics will want to transport that heat. This is called the Hadley circulation, which on Earth forms three cells per hemisphere. The part where air sinks is results in dry weather, which is why deserts on Earth generally form around ±30° latitude.
This picture looks like it has the same kind of circulation pattern, so let's draw an equator that puts the deserts at the right spot. That is not quite balanced, but it looks correct (except for those random white spots in the bottom left; let's assume they like random clouds in the Google Earth imagery). It actually implies there is a lot more water on Remnant. If the image is 512 pixels high from equator to North Pole, it implies 1024 pixels from pole to pole, or a circumference of 2048 pixels. (I swear I did not pick these round numbers.)
The problem we have next is trying to scale the map. Other attempts to do this have assumed similarity to Earth, but I want to avoid assuming anything about gravity or planetary density. Instead, let's take what canon tells us about the humans on Remnant. They are basically the same shape and same height as humans on earth, which means that they should walk at the same rate. I think this is somewhat invariant to things like local gravity -- g values of 7 to 12 should be similar enough. There are some anime physics going on, but for the most part, fall rates appear normal.
Using human walking as a yardstick, we need a journey big enough to actually be viewable on the map. Canon provides this as well: it tells you it took a six month journey to walk overland from Vale to Vacuo. This is sketched on the map above -- it's impossible to know their exact route, but it's certainly not the shortest.
Taking the Oregon Trail was a trip that took about six months and covered 2170 miles of wilderness, with 10 miles a day being a typical travel speed. But immigrants on the trail were traveling with all of their property! Things happened, and people got dysentery. If you're traveling light, with trained huntresses moving fast while foraging, I think 20 miles is reasonable. Spanish missions in California were placed about 25 miles apart to be about one day's walk away over roads. So lets go with 20 miles/day as a speed, or 32km/day. This would make the entire trip ~5800km.
This map is also very likely a Mercator projection, so let's scale our vectors. I'm going to be a little lazy here and approximate the sphere as flat pieces, assuming 30 north latitude for the whole journey, but let's go with it. We don't know the terrain anyway so it's in our margin of error.
segment = √( Δlatitude² + ( Δlongitude cos 30° )² )
segment 1 = √( 150² + (180 cos 30°)² ) = 216.33 px
segment 2 = √( 80² + ( 150 cos 30°)² ) = 152.56 px
Or 369px = 5800km, or one pixel of latitude = 15.72 km. Finally, a scale!
Taking this, we get a global circumference of 15.72 km/px * 2048px = 32200km. This produces a radius of Remnant of 5120km. This is good! This is in a region that we expect. Earth has a radius of 6370km, Mars has a radius of 3390km. If we adjust the travel time up or down, we still have something that is in the neighborhood of an actual Earth-like body. The land area would be significantly smaller at around ~45% of Earth's: Remnant would have 6.6e7 km² (assuming 80% ocean) compared to Earth's 14.8e7 km².
Even if we accept this smaller value, we can look at planets like Mercury in the solar system which have a higher density, and thus a higher surface gravity. There's no reason that Remnant couldn't have Earth's gravitational field of around 10 m/s². I think there's a good argument for there being a little less gravity, but not much less.
We could get some different results if we change travel time, travel speed, or routes, but nothing will change by an order of magnitude. We're still in the range for a rocky planet, or possibly a iron-rich rocky planet. (I almost said metal-rich here, but then I remembered that in astronomy silicon and oxygen are metals.)
In summary: the fandom isn't good at physics and geoscience, the animators aren't good at cartography. Somehow we ended up with something physical anyway.
Assumption 1: Hadley circulation is 3-celled like Earth, based on appearance.
Assumption 2: Humans on Remnant and Earth walk at a similar rate, based on character heights
Assumption 3: Months and days on Remnant are basically the same as months and days on Earth, based on translation convention
Assumption 4: Hunters can move roughly 20 miles a day, based on physical fitness and light travel
Assumption 5: Assume Remnant is a spherical object, rather than an oblate spheroid.
"Kitto daijoubu da yo." - Sakura Kinomoto