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contentbot@lemmy.caB to Today I Learned (TIL)@lemmy.ca · 1 year ago

TIL Colorado isn’t a rectangle and actually has 697 sides, mostly due to poor measurement tools

www.atlasobscura.com

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TIL Colorado isn’t a rectangle and actually has 697 sides, mostly due to poor measurement tools

www.atlasobscura.com

contentbot@lemmy.caB to Today I Learned (TIL)@lemmy.ca · 1 year ago
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Colorado Is Not a Rectangle—It Has 697 Sides - Atlas Obscura
www.atlasobscura.com
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America loves its straight-line borders. The only U.S. state without one is Hawaii—for obvious reasons.
  • Author: /u/crimson_dovah
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  • delirious_owl@discuss.online
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    1 year ago

    What would a rectangle even mean on a sphere?

    • Kogasa@programming.dev
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      1 year ago

      Four right angles.

      • delirious_owl@discuss.online
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        1 year ago

        So it doesn’t fit on a sphere at all?

        • Kogasa@programming.dev
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          1 year ago

          Good point. Four equal angles, then, although they will each have to be greater than 90 degrees.

          • delirious_owl@discuss.online
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            1 year ago

            I don’t think that would work for just 4 lines? I think you have to have arcs, not straight lines

            • Kogasa@programming.dev
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              1 year ago

              It’s possible to have an equiangular quadrilateral, i.e. whose sides are geodesics (the analogue of “straight line” on a sphere). The Gauss-Bonnet theorem implies their total interior angle is greater than 2pi, so four right angles can’t work.

              Here’s an interactive demo of quadrilaterals on the sphere: https://geogebra.org/m/q83rUj8r

              Notice that each side is a segment of a great circle, i.e. a circle that divides the sphere in half. That’s what it means for a path to be a geodesic on the sphere.

    • TonyTonyChopper@mander.xyz
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      1 year ago

      many boundary lines “in law” follow longitude/latitude great circles

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