geosphere (version 1.1.2)

distHorizon: distance to horizon

Description

Compute distance to the horizon at a given altitude. The earth is assumed to be smooth, i.e. mountains and other obstacles are ignored.

Usage

distHorizon(h, r=6378137)

Arguments

h

altitude, numeric >= 0. Should have the same unit as r

r

radius of the earth; default value is 6378137 m

Value

• A distance in units of h (default is meters)

References

http://williams.best.vwh.net/avform.htm#Horizon Bowditch, 1995. American Practical Navigator. Table 12.

Examples

distHorizon(1.80) # me
distHorizon(324)  # Eiffer tower