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Geodesy

Coordinate system on a sphere, the Haversine great-circle distance, and basic satellite geometry.

Great-circle distance

Worked Example

Distance NYC ↔ London (rough)

Given: Δ ≈ central angle 0.873 rad

  1. 1

    Arc length

    s = 6371 · 0.873

Worked Example

1° latitude in km

Given: Full circle = 360°

  1. 1

    Circumference

    2π·6371 ≈ 40030 km

Timed Game · 6 problems
02:00

Answer 6 problems in 2 min. Timer auto-stops.