+TEAM 360 Posted December 2, 2003 Share Posted December 2, 2003 It's probably been addressed before. Mileage from one point on the globe to the exact opposite location on the other side of the world: How is it measured when I am using the GPS? Around the surface of the Earth, or straight through the middle (straight line, point-to-point)? Quote Link to comment
+trippy1976 Posted December 2, 2003 Share Posted December 2, 2003 There is a pretty complicated formula that takes into account the curvature of earth. I don't know for certain, but believe in my heart that any respectable manufacturer would use this to be more accurate. This calculation, as fas as I know, assumes the earth is a sphere so you don't get 100% accuracy, but it's pretty good. victorymike is a pretty up on GPS info, you might try posting on MiGO, I don't think he makes it in here often. Quote Link to comment
+Team GPSaxophone Posted December 2, 2003 Share Posted December 2, 2003 Put in a waypoint that is exactly on the opposite side of the world, then do a GOTO. If the distance is equal to the diameter of the Earth in that spot, you'll know. Quote Link to comment
+TEAM 360 Posted December 2, 2003 Author Share Posted December 2, 2003 Put in a waypoint that is exactly on the opposite side of the world, then do a GOTO. If the distance is equal to the diameter of the Earth in that spot, you'll know. And how will I know what the diameter of the Earth would be in that spot? Hmmmm..... That deserves a Quote Link to comment
+Prime Suspect Posted December 2, 2003 Share Posted December 2, 2003 It's probably been addressed before.Mileage from one point on the globe to the exact opposite location on the other side of the world: How is it measured when I am using the GPS? Around the surface of the Earth, or straight through the middle (straight line, point-to-point)? It uses a Great Circle calculation, so yes, it is the distance over the surface. Quote Link to comment
+Team GPSaxophone Posted December 2, 2003 Share Posted December 2, 2003 Put in a waypoint that is exactly on the opposite side of the world, then do a GOTO. If the distance is equal to the diameter of the Earth in that spot, you'll know. And how will I know what the diameter of the Earth would be in that spot? Hmmmm..... That deserves a I thought you posted the answer in the title of the thread?! Quote Link to comment
thcri Posted December 2, 2003 Share Posted December 2, 2003 This is an interesting one. So help another newbie here, Make a waypoint on the other side?? How do I know where the other side is??? Can I tell by the cordinates of one side, can I sipher from the cordinates? murph Quote Link to comment
+Cornix Posted December 2, 2003 Share Posted December 2, 2003 How do I know where the other side is??? That's easy to calculate.. Take for example the coordinates N 44° / W 92°. The Other side is: S 44° / E 88°. (88 = 180 - 92) Cornix Quote Link to comment
+The Cheeseheads Posted December 3, 2003 Share Posted December 3, 2003 Perhaps manually set waypoints at the north pole and south pole, then create a route using the two points. If the distance is about 12,000 km, it's routing through the Earth's core, which would be some pretty treacherous bushwhacking. It it's about 20,000 km, it's using the circumference. A safer, although soggier trip. Quote Link to comment
Neo_Geo Posted December 4, 2003 Share Posted December 4, 2003 (edited) As Prime Suspect said, it uses the Great Circle path. A route from New York to Paris drawn on a flat map will looked curved, arcing off the coast of Maine, and over Nova Scotia, then arcing back down south of Ireland and Great Britain. If you take a piece of string and stretch it out as tight as it will go between NY and Paris on a world globe, the straight piece of string will follow this same path. Now, Believe it or not - drawing a Great Circle path between Baltimore, Maryland and Las Vegas, Nevada, if you zoom in on Baltimore, you will notice that the route actually starts out going slightly WNW - even though Las Vegas is very much to the WSW. It boggles the mind! Edited December 4, 2003 by Neo_Geo Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.