Geocenter
---------
The instantaneous transformation between CoN and CoM is realized by
+ the annual and semiannual ITRF2020 model
+ center of mass correction of ocean tidal loading (FES2022)

The geocenter must be added to CoM coordinates in TRF to get coordinates in CoN.

Data columns of gecenterCoM2CoN.txt.gz
- Time:   GPS [MJD]
- data0:  x in TRF [m]
- data1:  y in TRF [m]
- data2:  z in TRF [m]