$LastChangedDate: 27-Juil-2011 $

# CL_fr_G502ter

Gamma50 (Veis) to terrestrial frame vector transformation

## Calling Sequence

       [pos_ter,[vel_ter,jacob]] = CL_fr_G502ter(cjd,pos_G50,[vel_G50,ut1_utc])

## Description

- Converts position and (optionally) velocity vectors from Gamma50 (Veis) to the terrestrial ("Earth fixed") reference frame.

  The jacobian of the transformation is optionally computed.

- Notes:

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

- See Reference Frames for more details on the definition of reference frames.

## Parameters

cjd:

  modified julian day from 1950.0 (TUC) (1xN or 1x1)

pos_G50:

  position vector relative to Gamma50 (Veis) frame [m] (3xN or 3x1)

vel_G50:

  (optional) velocity vector relative to Gamma50 (Veis) frame [m/s] (3xN or 3x1)

ut1_utc:

  (optional) ut1-utc [seconds] (default is 0) (1xN or 1x1)

pos_ter:

  position vector relative to terrestrial frame [m] (3xN)

vel_ter:

  (optional) velocity vector relative to terrestrial frame [m/s] (3xN)

jacob:

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

## Authors

- CNES - DCT/SB

## Bibliography

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

## See also

- CL_fr_ter2J2000Mat

- CL_fr_G502terMat

- CL_fr_ter2G50

- CL_mod_sidTimeG50

## Examples

    // Conversion of position G50 to terrestrial
    pos_G50 = [[3500.e3;2500.e3;5800.e3] , [4500.e3;2100.e3;6800.e3]];
    cjd = [21010 , 21011];
    pos_ter = CL_fr_G502ter(cjd,pos_G50);

    // Conversion of position and velocity + jacobian
    pos_G50 = [[3500.e3;2500.e3;5800.e3] , [4500.e3;2100.e3;6800.e3]];
    vel_G50 = [[1.e3;3.e3;7.e3] , [2.e3;3.e3;6.e3]];
    cjd = [21010 , 21011];
    [pos_ter,vel_ter,jacob] = CL_fr_G502ter(cjd,pos_G50,vel_G50);