Geography & Earth
Advanced

Earth Curvature Drop

Approximate drop of the horizon over distance d.

Formula

h≈d22Rh \approx \frac{d^2}{2R}

Variables

dDistance
REarth radius

Example

Over 5 km the Earth curves away by about 5000²/(2·6.37×10⁶) ≈ 2 m.

Did You Know?

The Earth curves away about 8 cm per kilometer squared — why distant ships seem to sink below the horizon.

curvaturehorizonearth