CL_fr_bodyConvertMat

Description

• Computes the frame transformation from frame1 to frame2, which is characterized by a frame transformation matrix M and an angular velocity vector omega.

  By convention:

  - multiplying M by coordinates relative to frame1 yields coordinates relative to frame2.

  - omega is the angular velocity vector of frame2 wrt frame1, with coordinates in frame1.

• Available frames are :

  'ICRS': International Celestial Reference System

  'BCI': Body Centered Inertial

  'BCF': Body Centered body Fixed

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

  Available bodies are: "Mercury","Venus","Mars","Jupiter","Saturn","Uranus", "Neptune", "Sun" and "Moon"

• Notes :

  - The date "cjd" is relative to the TREF time scale.

  - The frame names and body names are case sensitive

  - Earth is not a valid body for this function. See CL_fr_convert.

  - GCRS (identical to ICRS in CelestLab) is also accepted as a frame name.

Parameters

body:

(string) Name of the body. ("Mercury","Venus","Mars","Jupiter","Saturn","Uranus", "Neptune", "Sun" or "Moon") (1x1)

frame1:

(string) Name of the initial frame. (1x1)

frame2:

(string) Name of the final frame. (1x1)

cjd:

Modified (1950.0) julian day (Time scale: TREF) (1xN)

tt_tref:

(optional) TT-TREF [seconds]. Default is %CL_TT_TREF. (1xN or 1x1)

M:

Frame transformation matrix from frame1 to frame2 (3x3xN)

omega:

Angular velocity vector of frame2 wrt frame1 with coordinates in frame1 [rad/s] (3xN)

Authors

• CNES - DCT/SB

Bibliography

• Report of the IAU/IAG working group on cartographic coordinates and rotational elements: 2009

See also

• CL_mod_IAUBodyAngles

• CL_fr_bodyConvert

• CL_fr_convertMat

Examples

cjd = CL_dat_cal2cjd(2010,02,03,05,35,25); // ICRS to BCF [M,omega] = CL_fr_bodyConvertMat("Mars","ICRS","BCI",cjd);