How can I measure the Earth’s Radius using a GPS?
I need to measure the Earth’s radius using only a GPS devise and a compass (as to stay on the same meridian.) I know I need to note two different locations as to get the arc length, but after that, I’m at a loss.


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pick four points that line up started with the north pole, then two points on the equator that lines up with the south pole as well as north. this gives you the circumference , from there you can calculate radius and diameter
May be you can go north/south and see the change in latitude and the distance traveled. Then use radius = (distance traveled) / (change in latitude * pi / 180)