Name

CL_fr_G502J2000Mat — Gamma50 (Veis) to EME2000 (J2000) matrix

Calling Sequence

   M=CL_fr_G502J2000Mat(cjd,[,ut1_utc[,xp,yp[,dPsi,dEps[,conv]]]])
   
   

Description

  • Computes the frame transfer matrix from Gamma50 (Veis) to EME2000 frame.

    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

  • To convert a vector vect_G50 to vect_J2000, you need to use the (hyper)matrix M : vect_J2000 = M * vect_G50

    To convert a vector vect_J2000 to vect_G50, you need to use the (hyper)matrix M' : vect_G50 = M' * vect_J2000

  • Last update : 27/6/2008

Parameters

cjd:

CNES Julian Day (+ut/24). Date of the Gamma50 (Veis) frame. (1xN)

ut1_utc :

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

xp :

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

yp :

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

dPsi :

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

dEps :

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

conv :

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

M:

GAMMA50 to J2000 matrix (3x3xN)

Authors

CNES - DCT/SB

Bibliography

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

See also

CL_fr_ter2J2000Mat, CL_fr_teme2J2000Mat, CL_fr_H0n2J2000Mat

Examples

//conversion of 3 coordinates
//tpv: time, position and velocity
tpv = [3952930.5 3127929.25 4128420.75 -6244.61914 3103.701904 3619.265381]';
tpv(:,2) = [3945680.5 3125978.25 5687420.75 -6654.61914 4563.701904 3123.265381]';
cjd = 20870+125/86400;
position_veis = tpv(1:3,:);
velocity_veis = tpv(4:6,:);
M = CL_fr_G502J2000Mat(cjd);
position_J2000 = M*position_veis;
velocity_J2000 = M*velocity_veis;
coord_J2000 = [position_J2000;velocity_J2000];

See 'CelestLab > Demos > ORBIT_PROPERTIES > beta_sun' for more examples