The altitude (elevation from the horizon), azimuth and distance of a point B from A are the coordinates of the Topocentric Coordinate System as typically used in astronomy to aim your telescope to a heavenly body. It can be also of use to know where an airplane is in the sky with respect to an observer on Earth.

altitude_azimuth_distance(a, b)

Arguments

a

the observer position: a vector of longitude, latitude (in decimal degrees) and altitude (in meters) in WGS84

b

the observed position: a vector of longitude, latitude (in decimal degrees) and altitude (in meters) in WGS84

Value

the coordinates in North-East-Up of the observed, B, with respect to the observer A. A vector of altitude (elevation from the horizon) in decimal degrees, azimuth) in decimal degrees and distance in meters.

See also

Examples

if (FALSE) { # sensor (longitude, latitude, altitude) a <- c(49.47, 7.697, 274) # aircraft (longitude, latitude, altitude) b <- c(49.52, 7.803, 6401) altitude_azimuth_distance(a, b) }