Name

CL_fr_ter2G50 — Gamma50 (Veis) to G50restrial frame vector transformation

Calling Sequence

   [pos_G50,[vel_G50,jacob]] = CL_fr_ter2G50(cjd,pos_ter,[vel_ter,ut1_utc])
   
   

Description

  • Given the positions pos_ter and optionnaly vel_ter in the terrestrial frame, this function computes positions pos_G50, and optionnaly vel_G50 in the Gamma50 (Veis) frame. Jacobian of the transformation is also optionnaly computed.

    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.

  • Last update : 27/6/2008

Parameters

cjd:

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

pos_ter:

position in terrestrial frame [X;Y;Z] (3xN)

vel_ter:

(optionnal) vector in terrestrial frame [X;Y;Z] (3xN)

ut1_utc :

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

pos_G50:

position in G50 (Veis) frame [X;Y;Z] (3xN)

vel_G50:

(optional) velocity in G50 (Veis) frame [X;Y;Z] (3xN)

jacob:

(optional) jacobian of the transformation [d(x,y,z,vx,vy,vz)_G50/d(x,y,z,vx,vy,vz)_ter] (6x6xN)

Authors

CNES - DCT/SB

Bibliography

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

See also

CL_fr_ter2J2000Mat, CL_fr_G502terMat, CL_fr_G502ter, CL_mod_sidTimeG50

Examples

// Conversion of position ter to G50
pos_ter = [ [3952930.5;3127929.25;4128420.75] , [3945680.5;3125978.25;5687420.75]];
cjd = [21010 , 21011];
pos_G50=CL_fr_ter2G50(cjd,pos_ter);

// Conversion of position and velocity : ter to G50  + jacobian
pos_ter = [ [3952930.5;3127929.25;4128420.75] , [3945680.5;3125978.25;5687420.75]];
vel_ter = [ [1.e3;3.e3;7.e3] , [1.e3;3.e3;7.e3]];
cjd = [21010 , 21011];
[pos_G50,vel_G50,jacob]=CL_fr_ter2G50(cjd,pos_ter,vel_ter);