Rotation Matrix from EQD to EQJ

Calculates a rotation matrix from equatorial of-date (EQD) to J2000 mean equator (EQJ).

Usage

astro_rotation_EQD_EQJ(time)

Arguments

time

A POSIXct object representing the date and time at which the Earth's equator defines the source orientation.

Value

A rotation matrix that converts EQD to EQJ.

Details

This is one of the family of functions that returns a rotation matrix for converting from one orientation to another.

Source: EQD = equatorial system, using equator of the specified date/time.

Target: EQJ = equatorial system, using mean equator at J2000 epoch.

Examples

astro_rotation_EQD_EQJ(Sys.time())
#>             [,1]          [,2]          [,3]
#> [1,] 0.999979467 -5.877511e-03 -2.553669e-03
#> [2,] 0.005877401  9.999827e-01 -5.046285e-05
#> [3,] 0.002553921  3.545288e-05  9.999967e-01