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astrolibR (version 0.1)

eci2geo: Convert Earth-centered inertial coordinates to geographic spherical coordinates

Description

Convert Earth-centered inertial coordinates to geographic spherical coordinates

Usage

eci2geo(eci_xyz, jdtim)

Arguments

eci_xyz
ECI [X,Y,Z] coordinates (in km), can be an array [3,n] of n such coordinates.
jdtim
Julian Day time, double precision. Can be a 1-D array of n such times.

Value

lat, lon, alt
3-element array of geographic [latitude,longitude,altitude], or an array [3,n] of n such coordinates, double precision

Details

Converts from ECI (Earth-Centered Inertial) (X,Y,Z) rectangular coordinates to geographic spherical coordinates (latitude, longitude, altitude). JD time is also needed as input.

ECI coordinates are in km from Earth center. Geographic coordinates are in degrees/degrees/km. Geographic coordinates assume the Earth is a perfect sphere, with radius equal to its equatorial radius.

gcoord can be further transformed into geodetic coordinates (using astrolib geo2geodetic) or into geomagnetic coordinates (using geo2mag)

See Also

ct2lst

Examples

Run this code
eci2geo(c(6378.137+600, 0, 0), 2452343.38982663)  # result 0.0000000  232.27096 600.00000

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