Marine & Nautical

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Great-Circle Distance

Shortest distance between two points on the globe.

Formula

d = R\arccos(\sin\phi_1\sin\phi_2 + \cos\phi_1\cos\phi_2\cos\Delta\lambda)

Variables

dDistance

REarth radius

φ_1,φ_2Latitudes

ΔλLongitude difference

Example

Used to plot the shortest ocean crossing between two ports.

Did You Know?

Great-circle routes look curved on flat maps but are the true shortest path — why flights over oceans arc north.

marine navigation great circle

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