For example, Britain’s national mapping organisation’s brand is associated in our national consciousness with going to a small shop in a quaint village to get a map showing how to walk up a mountain. It’s called Ordnance Survey. If that sounds like Artillery Research to you, that’s because the project started because the king wanted to know how to accurately bomb Scotland.

    • PM_Your_Nudes_Please@lemmy.world
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      3 days ago

      Even weirder is that the most efficient way to steer them is not in straight lines. Because the most efficient way to traverse a sphere is on a slight curve.

      Get a string and pick two points along the equator on a globe. Stretch the string tight. It’ll bend into a slight curve above or below the equator (instead of following the equator directly) as you pull it, because the shortest distance between two points on a globe is not a straight line.

      • Captain Aggravated@sh.itjust.works
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        2 days ago

        You’re talking about great circle routes, which is why long distance airplane flights look strangely curved on most flat projection maps.

        What’s even more fun is Coriolis force, which in the Northern hemisphere will deflect your path slightly to the right. Pilots tend not to think about it because the wind is a much greater force for deflection but it’s there.

      • juliebean@lemm.ee
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        3 days ago

        of course the shortest distance is a straight line, that’s literally the definition of a straight line.

        • PM_Your_Nudes_Please@lemmy.world
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          3 days ago

          The point is that you can’t follow a straight line on a globe, because that’s longer than taking a slight curve. If you take a straight line, you follow the entire circumference of the earth, but following a curved path allows you to avoid some of the width. Basically, the circumference means a straight line is more curved than a curved path.

          • juliebean@lemm.ee
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            2 days ago

            i don’t even understand what you think ‘straight’ and ‘curved’ even mean at this point.

            • PM_Your_Nudes_Please@lemmy.world
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              9 hours ago

              I’m talking about how in this image, the upper curved line is shorter than the straight line that follows the equator:

              Because the curvature of the earth is greater than the curvature of the upper line. So by taking the upper curved line, you “skip” some of the curvature of the earth.

              • juliebean@lemm.ee
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                9 hours ago

                that line only appears straight because of the map projection being used. the one that appears curved is actually straight on a globe. you could construct a different projection that made that straight line appear straight (though other straight lines would thereby be distorted instead). latitude lines are not straight lines, and never have been, except the equator.

          • asret@lemmy.zip
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            2 days ago

            Isn’t it still a straight line from the perspective of someone travelling it? It just appears curved because you’re looking at it from outside the curved surface.