Name

CL_fr_G502terMat — Gamma50 (Veis) to terrestrial matrix

Calling Sequence

   M=CL_fr_G502terMat(cjd[,ut1_utc])
   
   

Description

  • Computes the frame transfer matrix from Gamma50 to terrestrial frame at given dates.

    Gamma50 (Veis) (Veis frame at date) is defined as:

    - origin at the center of the Earth

    - plan OXY is the true equatorial plan of the date

    - OX axis goes through the Veis equinox of the date

    - OZ axis goes through the true celestial pole of the date

    - OY completes the orthonormal frame

    Transformation from Gamma50 to terrestrial frame is a single rotation of the Veis sideral time(as calculated in CL_mod_sidTimeG50) around the Z axis.

  • To convert a vector vect_G50 to vect_ter, you can use the (hyper)matrix M : vect_ter = M * vect_G50

    To convert a vector vect_ter to vect_G50, you can use the (hyper)matrix M' : vect_G50 = M' * vect_ter

    For big hypermatrixes, it is faster to use the functions CL_fr_G502ter and CL_fr_ter2G50

  • Last update : 27/6/2008

Parameters

cjd:

CNES Julian dates (dates of the Gamma50 (Veis) frame) (1xN)

ut1_utc :

(optional) ut1-utc [seconds] (default is 0) (1xN)

M:

Gamma50 (Veis) to terrestrial frame transfer (hyper)matrix (3x3xN)

Authors

CNES - DCT/SB

Bibliography

1 CNES - MSLIB FORTRAN 90, Volume R (mr_tsid_veis)

See also

CL_fr_ter2J2000Mat, CL_fr_G502ter, CL_fr_ter2G50, CL_mod_sidTimeG50, CL_fr_teme2J2000Mat, CL_fr_H0n2J2000Mat

Examples

// Conversion G50 to terrestrial
pos_G50 = [ [3952930.5;3127929.25;4128420.75] , [3945680.5;3125978.25;5687420.75]];
cjd = [21010 , 21011];
M=CL_fr_G502terMat(cjd);
pos_ter = M * (pos_G50);
pos_ter = CL_fr_G502ter(cjd,pos_G50);

// Conversion terrestrial to G50
pos_ter = CL_co_sph2car([ [0;%pi/4;%CL_eqRad+700.e3] , [0;-%pi/4;%CL_eqRad+800.e3]]);
cjd = [21010 , 21011];
M=CL_fr_G502terMat(cjd);
pos_G50 = M' * (pos_ter);
pos_G50 = CL_fr_ter2G50(cjd,pos_ter);