Calculate the "Hidden Height"

- Hidden by the ground we stand on
- Disappeared behind the horizon

 On a sphere with a radius of 6371 km.
-Your viewing height is 345 m
-You are looking at an object 123 km away
-The object is hidden by 842 m of curvature
-The horizon is 66 km away

Curvature of the Earth

From Wikipedia, the free encyclopedia

The curvature of the earth is understood to be the fact that the shape of the earth corresponds approximately to a sphere and therefore deviates from a tangential plane even over short distances. Because of the curvature of the earth, height measurements must be corrected accordingly.


Calculated with an average Earth radius of 6371 km, the ideal Earth surface deviates from a tangential plane downwards (radially, towards the Earth's centre) as follows:

0.8 mm per 100 m
20 mm at 500 m
78 mm at 1000 m
1.96 m by 5000 m
7.85 m to 10,000 m