I am using SPICE to read and store Chebyshev coefficients to then compute position of Solar System bodies in my navigation software (see this post).
The coefficients are defined with respect to the frame center definition : Earth-Moon barycenter for the Earth and Moon and Solar System barycenter for other planets. Example for de440.bsp :
BRIEF -- Version 4.1.0, September 17, 2021 -- Toolkit Version N0067
Summary for: de440.bsp
Bodies: MERCURY BARYCENTER (1) w.r.t. SOLAR SYSTEM BARYCENTER (0)
VENUS BARYCENTER (2) w.r.t. SOLAR SYSTEM BARYCENTER (0)
EARTH BARYCENTER (3) w.r.t. SOLAR SYSTEM BARYCENTER (0)
MARS BARYCENTER (4) w.r.t. SOLAR SYSTEM BARYCENTER (0)
JUPITER BARYCENTER (5) w.r.t. SOLAR SYSTEM BARYCENTER (0)
SATURN BARYCENTER (6) w.r.t. SOLAR SYSTEM BARYCENTER (0)
URANUS BARYCENTER (7) w.r.t. SOLAR SYSTEM BARYCENTER (0)
NEPTUNE BARYCENTER (8) w.r.t. SOLAR SYSTEM BARYCENTER (0)
PLUTO BARYCENTER (9) w.r.t. SOLAR SYSTEM BARYCENTER (0)
SUN (10) w.r.t. SOLAR SYSTEM BARYCENTER (0)
MERCURY (199) w.r.t. MERCURY BARYCENTER (1)
VENUS (299) w.r.t. VENUS BARYCENTER (2)
MOON (301) w.r.t. EARTH BARYCENTER (3)
EARTH (399) w.r.t. EARTH BARYCENTER (3)
Start of Interval (ET) End of Interval (ET)
----------------------------- -----------------------------
1549 DEC 31 00:00:00.000 2650 JAN 25 00:00:00.000
I want to have all coefficients defined in the same frame center.
So, is there a way to change the frame center definition of Chebyshev coefficients without compute bodies position ?
For example is it possible to have Chebyshev coefficients of the Earth w.r.t the Solar System barycenter ?