$LastChangedDate: 27-Juil-2011 $

# CL_fr_J20002ter

EME2000 (J2000) to terrestrial frame vector transformation

## Calling Sequence

       [pos_ter,[vel_ter,jacob]] = CL_fr_J20002ter(cjd,pos_J2000,[vel_J2000,ut1_utc,xp,yp,dPsi,dEps,conv])

## Description

- Converts position and (optionally) velocity vectors from EME2000 to the terrestrial ("Earth fixed") reference frame.

  The jacobian of the transformation is optionally computed.

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

## Parameters

cjd:

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

pos_J2000:

  position vector relative to EME2000 [m] (3xN or 3x1)

vel_J2000:

  (optional) velocity vector relative to EME2000 [m/s] (3xN or 3x1)

ut1_utc :

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

xp :

  (optional) x polar coordinate [radians] (default is 0) (1xN or 1x1)

yp :

  (optional) y polar coordinate [radians] (default is 0) (1xN or 1x1)

dPsi :

  (optional) Nutation corrections [radians] (default is 0) (1xN or 1x1)

dEps :

  (optional) Nutation corrections [radians] (default is 0) (1xN or 1x1)

conv :

  (optional) Convention IERS. Only iers 1996 (Lieske/Wahr) is implemented (default is "iers_1996")

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 (6x6xN)

## Authors

- CNES - DCT/SB

## Bibliography

- 1) IERS Conventions (1996), Dennis D. McCarthy

- 2) Explanatory Supplement to the Astronomical Almanac, Seidelman (1992)

## See also

- CL_fr_ter2J2000Mat

- CL_fr_J20002ter

## Examples

    // Conversion J2000 to terrestrial
    pos_J2000=[[3500.e3;2500.e3;5800.e3] , [4500.e3;2100.e3;6800.e3]];
    cjd = [21010 , 21011];
    pos_ter = CL_fr_J20002ter(cjd,pos_J2000);
    M=CL_fr_ter2J2000Mat(cjd);
    pos_ter_2 = M'*pos_J2000;

    // Conversion J2000 to terrestrial
    pos_J2000 = [1000.e3;7078.e3;700.e3];
    vel_J2000 = [4.e3;4.2e3;3.e3];
    cjd = 20010;
    [pos_ter,vel_ter,jacob] = CL_fr_J20002ter(cjd,pos_J2000,vel_J2000)