Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
What direction would?
Fayetteville Arkansas to Jerusalem Israel what direction would I be facing
2 Answers
- ?Lv 74 weeks ago
Latitude and longitude of Fayetteville = 36.1 N, 94.2 W.
Lat & long of Jerusalem = 31.8 N, 35.2 E.
Because Jerusalem is slightly closer to the equator than Fayetteville is, you might THINK that the right way to face J from F would be slightly south of east. You'd be wrong.
The latitude circles, if you are traveling eastward, curve continuously to the left, whereas we are looking for a direct route that goes straight over the horizon without turning left or right.
Consider a triangle whose vertices are F, J, and N (the N being 90.0 north, the pole). Angle FNV is 94.2 + 35.2 = 129.4 degrees. Side j (opposite vertex J) is 90 - 36.1 = 53.9 degrees. Side f (opposite vertex F) is 90 - 31.8 = 58.2 degrees. Side n (the shortest air route) is found from the spherical law of cosines:
cos(n) = cos(f)cos(j) + sin(f)sin(j)cos(N)
= cos(58.2)cos(53.9) + sin(58.2)sin(53.9)cos(129.4)
= -0.125392 => n = 97.2 degrees.
Then, to find the heading from F to J, we use the spherical law of sines:
sin(F)/sin(f) = sin(N)/sin(n) =>
sin(F) = sin(58.2)*sin(129.4) / sin(97.2) = 0.661960 =>
angle F (at Fayetteville) = 41.4 degrees.
This provides the rather startling result that if you want to face Jerusalem along the shortest route over the horizon, you should face 41 degrees NORTH of east. Weird, huh ?