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saraid216 | 10 years ago

That's true for large chunks, but I'd imagine 3 meters is small enough to remain useful well past the 85 degrees latitude mark. Straight Dope informs me that the circumference up there is approximately 24k miles, which becomes 38,624,256 meters which means approximately 1 million divisions.

As long as the system works, what's the big deal?

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anamexis|10 years ago

24k miles is Earth's circumference at the equator, not 85 degrees latitude.

saraid216|10 years ago

Dammit. I thought I had been careful enough to get the correct number.

Alright. Picking the simplest formula off Wikipedia, cosine of 85 degrees is ~0.0871557 times a (6378137m) times pi is ~1746383.9m for the circumference. That's still approximately 500k squares at the exact latitude. My point is one of the sheer magnitude still available.

What I should do is calculate how many decimal points down from 90 degrees 3 meters is and get that circumference, since that's the low bound, but I'm not really feeling up to the number-plugging.

I could be incorrect about what a is; I presumed it is the semi-major axis on WGS84, but I might have picked the wrong thing.

...

Ooh. I forgot there's a Wolfram|Alpha. ... And 10 minutes later I haven't convinced the input parsing to give me what I want. Oh well.