Orthodromic navigation - Alchetron, The Free Social Encyclopedia

The orthodromic navigation (related to orthodromic course; from the Greek ορtóς, right angle, and δρóμος, path) is a way to navigate following an arc of great circle corresponding to the shortest distance between two points on the globe.

Since the Earth is roughly a sphere, the orthodromic distance of the is often used by mariners to find the distance between two coordinates (knowing its longitude and its latitude) on a map, and the course to be taken to go from one to the other.

Calculation

gc ⁡ ( δ , λ , δ ′ , λ ′ ) = 2 R arcsin ⁡ sin 2 ⁡ ( δ ′ − δ 2 ) + cos ⁡ δ ⋅ cos ⁡ δ ′ ⋅ sin 2 ⁡ ( λ ′ − λ 2 )

R is the radius of the earth ≈ 6.367.000 meter). δ is the latitud (in radians). λ is the longitude (in radians). g c is the great circle arc, the shortest path between two points on the earth's globe

References

Orthodromic navigation Wikipedia

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