I wonder how anyone can think that the placement of an arbritrarily chosen coordinate net on the globe will change the actual direction from A to B.
Suppose there were no coordinate system, and all we had was the globe and points A and B on it. No doubt, all would agree on what would constitute the direction from A to B: it would be what a piece of string would do when pulled taut between the points. Or the way in which a car would have to be driven over the surface when only going 'straight ahead'. To be sure, one could take the other way round; but this would still concern the same great circle. Now, add two more points; for the sake of argument, let these be called N and S and be opposite each other on the globe. Draw a family of lines from N to S, spread out all around the globe. We could call them 'meridians', if we like. Does the existence of these meridians miraculously change the position of the taut string, or does it make the car suddenly drive differently? One may certainly construct a curve from A to B which intersects all the meridians at equal angles. But the position of such a curve on the globe would be entirely dependent on the chosen locations for N and S. It seems humorous to me that anyone could think that the direction to Mecca should correspond to (the start of) such an arbitrary curve, - especially when one considers that Mercator projection did not exist at the time this rule was postulated. Rudolf Van: sundial [mailto:[email protected]] Namens Brent Verzonden: donderdag 24 september 2015 22:12 Aan: [email protected] Onderwerp: Re: due east photos I think you can face Mecca from 4 directions: 1. along great circle shortest direction 2. along great circle longest direction 3. along constant compass method shortest direction 4. along constant compass method longest direction I wonder if it says in Koran to face Mecca in shortest direction? brent
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