Analysis Reports

Below is a table of some types of analysis reports & products produced by ILRS analysis and associate analysis centers for station coordinates, EOP, the ITRF, and the Earth’s gravity field.

For Lunar Laser Ranging (LLR) resources please see: https://ilrs.gsfc.nasa.gov/science/scienceContributions/lunar_resources.html

Center Satellite(s) Technique Location Filenames, or Report Type & Location
Agenzia Spaziale Italiana (ASI)1 LAGEOS-1,-2; LARES-2;
Etalon-1,-2		 7-day arcs, Daily Combination, stations + EOP (ILRSA) CDDIS & EDC ilrsa.pos+eop.YYMMDD.v190.sum.gz
ilrsa.pos+eop.YYMMDD.v190.snx.gz
Agenzia Spaziale Italiana (ASI)1 LAGEOS-1,-2; LARES-2;
Etalon-1,-2		 7-day arcs, Weekly Combination, stations + EOP (ILRSA) CDDIS & EDC ilrsa.pos+eop.YYMMDD.v90.sum.gz
ilrsa.pos+eop.YYMMDD.v90.snx.gz
Agenzia Spaziale Italiana (ASI)1 LAGEOS-1,-2; LARES-2;
Etalon-1,-2		 7-day arcs, Weekly Orbit Combination (ILRSA) CDDIS & EDC ilrsa.orb.$SATELLITE.YYMMDD.vNN.sum.gz
ilrsa.orb.$SATELLITE.YYMMDD.vNN.sp3.gz,
for vNN = v80, v90.
UMBC, GESTAR II & NASA GSFC (JCET)2 LAGEOS-1,-2; LARES-2;
Etalon-1,-2		 7-day arcs, Weekly Combination, stations + EOP (ILRSA) CDDIS & EDC Ilrsb.pos+eop.YYMMDD.v90.sum.gz
CODE IGS Analysis Center3 Galileo, Glonass, GPS, BeiDou, QZSS Comparison of SLR data to Microwave Orbits CDDIS & EDC Distributed via SLR-Report:
https://edc.dgfi.tum.de/en/mailing_lists/slr_report/
https://cddis.nasa.gov/archive/slr/slreport/
Chinese Academy of Sciences, Shanghai4 LAGEOS-1,-2;
LARES-2; Etalon-1,-2		 LAGEOS 3-day arc CDDIS & EDC Distributed via SLR-Report:
https://edc.dgfi.tum.de/en/mailing_lists/slr_report/
https://cddis.nasa.gov/archive/slr/slreport/
Goddard Space Flight Center (GSFC)5 TOPEX;
Jason-1,2,3; Sentinel-6A; Sentinel-6B		 10-Day arcs using
SLR+DORIS data		 CDDIS & IGN sp3 files distributed by the IDS Data Centers
CDDIS: https://cddis.nasa.gov/archive/doris/products/orbits/gsc/
IGN: ftp://doris.ign.fr/pub/doris/products/orbits/gsc/
Hitotsubashi University6 LAGEOS-1,-2; LARES-2; Etalon-1,-2; Ajisai; Stella; Starlette; LARES LAGEOS 1-2; Etalon 1-2, and LARES-2; Analysis Reports every 6 hrs. CDDIS https://geo.science.hit-u.ac.jp/slr/bias/
CDDIS: https://cddis.nasa.gov/archive/reports/slrhitu/
Joint Center for Earth Systems Technology, NASA Goddard & Univ. of Maryland, Baltimore County (JCET)7 LAGEOS-1, -2; LARES-2;
Etalon-1, -2		 7-days for all satellites,
Daily SLR bias report.		 CDDIS CDDIS: https://cddis.nasa.gov/archive/reports/slrjcet/
Mission Control Center (MCC)8 LAGEOS-1, Larets, Westpac 7-day arcs CDDIS CDDIS: https://cddis.nasa.gov/archive/reports/slrmcc/
Natural Environment Research Council (NERC) Space Geodesy Facility (NSGF)9 LAGEOS-1,2; LARES-2, Etalon-1, -2 Simultaneous Arc and 7-day Orbital Arc SGF website Satellite CPF Prediction Comparison & CPF Comparison Residuals: http://sgf.rgo.ac.uk/qualityc/
AC, AAC Product contacts:
  1. ASI. V. Luceri, D. Sarrocco.
  2. JCET. M. Kuzmicz-Cieslak (UMBC), K. Evans (UMBC), F. Lemoine (NASA GSFC).
  3. CODE IGS AC: R. Dach (CODE), U. Meyer (CODE).
  4. SHAO ACC. X. Wang (SHAO), Y. Chen. (SHAO).
  5. GSFC (precise orbits for altimetry satellites). N. Zelensky (ESSIC/UMD), F. Lemoine (NASA GSFC).
  6. Hitotsubashi University. T. Otsubo.
  7. JCET AAC. M. Kuzmicz-Cieslak (UMBC).
  8. MCC.
  9. NSGF. A. Susnik, G. Appleby.

Other SLR-derived Analysis Products:

  • NASA GSFC (B. Loomis & K. Rachlin), Low degree gravity solutions based on SLR data from the geodetic satellites (LAGEOS-1, LAGEOS-2, Starlette, Ajisai, Larets, LARES, LARES-2). (https://earth.gsfc.nasa.gov/geo/data/slr).
    1. Technical Note 14 C20/C30 product (GRACE/GRACE-FO data span).
    2. Weekly 5x5+C61/S61 product (Jan 2000 – present). [generally ~1-2 month latency]
    3. Long-term C20 (June 1976 – July 2026).
  • The University of Texas at Austin, Center for Space Research (J. C. Ries, M K. Cheng), Degree two Coefficients derived from SLR.
    https://www2.csr.utexas.edu/grace/csr-slr-degree2.html
    1. Variations of C20 (1976 – present).
    2. Complete degree two harmonics (C20, C21, S21, C22, S22), compatible with GRACE/RL06 processing (2002-present).
  • CNES/Groupe de Recherche de Géodésie Spatiale (GRGS), gravity fields recovered from GRACE GPS and K-band range-rate data, and from the SLR data of 5 satellites: LAGEOS-1/2, Starlette, Stella and Ajisai (J.M. Lemoine, S. Bourgogne, P. Gégout, F. Renquin).
    (https://grace.obs-mip.fr/variable-models-grace-lageos/introduction-grace-solutions/)
    Reference: Lemoine J-M, Bourgogne S, Gégout P, et al (2026.) “22 years of time-variable gravity field determination from GRACE and GRACE Follow-On: the CNES/GRGS RL05 solution”. J. Geodesy, 100:20 doi:10.1007/s00190-026-02040-1.
  • Other gravity models derived from SLR data (in whole or in part) for finite time spans are available from the ICGEM (International Center for Global Earth Models): https://icgem.gfz.de/sl/temporal#_04_SLR_
  • The University of Texas at Austin, Center for Space Research (J.C. Ries). 60-day estimates of geocenter from LAGEOS-1+LAGEOS-2, from 1998 to present (updated every 2 months): https://download.csr.utexas.edu/pub/slr/geocenter/

Reanalysis Reports and Products for the ITRF:

Current ITRF model:

ILRS Contributed Series for the Development of ITRF2020:

Past ITRF models: