Rotation Matrix from ECT to EQJ

Calculates a rotation matrix from true ecliptic of date (ECT) to J2000 mean equator (EQJ).

Usage

astro_rotation_ECT_EQJ(time)

Arguments

time

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

Value

A rotation matrix that converts ECT to EQJ.

Details

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

Source: ECT = ecliptic system, using true equinox of the specified date/time.

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

Examples

astro_rotation_ECT_EQJ(Sys.time())
#>              [,1]         [,2]         [,3]
#> [1,] 9.999795e-01 -0.005877511 -0.002553669
#> [2,] 6.408302e-03  0.917486912  0.397714344
#> [3,] 5.387116e-06 -0.397722542  0.917505738