Subject: [SLR-Mail]  No.2879: ILRS Data Handling File, SLRF2020 SINEX file and Eccentricity Files have  been updated.
From: Lemoine, Frank G. (GSFC-61A0) <frank.g.lemoine@nasa.gov>

Author:  F.G. Lemoine

The ILRS Analysis Standing Committee (ASC) has released updates to the following files:

  1.  Data Handling File:  ILRS_Data_Handling_File_20250513.snx
  2.  Eccentricity Files:    slrecc.250513.ILRS.une.snx.gz, slrecc.250513.ILRS.xyz.snx.gz
  3.  SLRF2020 Positions & Velocities:   SLRF2020_POS+VEL_2025.05.13.snx
The files are located as follows:
   e.g. https://cddis.nasa.gov/archive/slr/slrecc/   | Eccentricity files
https://ilrs.gsfc.nasa.gov/docs/2025/ILRS_Data_Handling_File_20250513.snx  (DHF update)
https://ilrs.gsfc.nasa.gov/docs/2025/SLRF2020_POS+VEL_2025.05.13.snx (SLRF2020 update)

These files include the following updates that have been applied since the start of 2025:


  1.  Updates to the station positions for Tsukuba (Japan, 7306) and Yebes (7817).

Note that the coordinates for Tsukuba (7306, TKBL) include a discontinuity on 2024-01-01

      to handle the co-seismic displacement due to the Noto earthquake.

The new Tsukuba coordinates were obtained from a stacking of normal equations and SLR data

     from LAGEOS-1, LAGEOS-2, LARES & LARES-2 for 2022-2023 and 2024-2025 (1st quarter).



  1.  Addition of the new discontinuities for various stations from ITRF2020-u2023:
         • 1890  A01 -> A02 at 22:264:00000
         • 7105  A01 -> A02 at 20:232:00000

  • 7396  A01 -> A02 at 20:274:00000

  • 7501  A02 -> A03 at 21:104:00000

  • 7835  A02 -> A03 at 94:012:00000
          • 7841  A01 -> A02 at 11:121:00000


  1.  Addition of station coordinates for the new OmniSLR station at Ishioka (7317, ISHL).



  1.  Addition of provisional (placeholder) coordinates for the anticipated new SLR station at Xian, China (7329, NTSC).



  1.  The updated eccentricity files now include values for Ishioka (7317, ISHL) and Xian (7329, NTSC).  Note the large “Z” component of the eccentricity vector for Ishioka (7317) of 1.54 m.


  1.  The Data Handling File (DHF) now includes range-bias data for LARES-2. In addition range-bias data was updated through the end of 2024.

Please direct any questions to the Mathis Bloßfeld @ Analysis Standing Committee (ASC) and to the ILRS Central Bureau.


F.G.Lemoine
On behalf of the ILRS CB & ILRS ASC.