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History

Prior to ILRS establishment, international workshops on Laser Satellite Ranging were sponsored by the Committee on Space Research (COSPAR) Panel 1A and the International Astronomical Union (IAU) starting in 1973. In 1975 the International Association of Geodesy (IAG) formed a Central Bureau for Satellite Geodesy which took up sponsorship of the workshops. 1980's saw the formation of the Commission for coordination of Space Techniques for geodesy and Geodynamics (CSTG), a joint commission of the IAG, the IAU, and COSPAR. In response to the CSTG president in 1995, proposals of participation in an International Laser Tracking Network were considered, patterned after a similar Global Positioning System service.

The draft ILRS Terms of Reference were presented and approved on 13 June 1997 at the Subcommission General Assembly in Maratea, Italy. Comments were taken from the community and incorporated where appropriate in the draft. The ILRS Terms of Reference and Working Group Charters were also posted on the Subcommission Web Site.


In the last quarter of 1997, Dr. John Degnan, the CSTG SLR/LLR Subcommission Chairman, and Dr. Bob Schutz, SLR Representative to the IERS Directing Board, drafted a Joint CSTG/IERS Call for Participation in the new service. Following a final review by the SLR/LLR Subcommission Steering Committee, the CSTG President, and the IERS Directing Board, the Call was distributed on 24 January 1998 via SLRmail, IGSmail, and SGGmail with proposals due by 31 March 1998. The Call requested proposals for a new ILRS Central Bureau and the various operational components which make up the ILRS, i.e., Tracking Stations and Subnetworks, Operations Centers, Analysis and Associate Analysis Centers, as well as Global and Regional Data Centers. The proposals were evaluated at a special meeting of the CSTG SLR/LLR Subcommission Steering Committee on 18 April 1998 held in conjunction with the European Geophysical Society (EGS) Symposia in Nice, France. The Steering Committee findings were presented the following day to both the CSTG Executive Board, chaired by Prof. Gerhard Beutler, and to the IERS Directing Board, chaired by Dr. Christoph Reigber. Both boards approved the Subcommission's deliberations. The IERS Directing Board appointed Dr. Bob Schutz as the voting IERS Representative on the new ILRS Governing Board. The approved responses to the Joint Call were then presented at the CSTG SLR/LLR Subcommission General Assembly on 21 April 1998.


The response by the SLR community to the Joint Call was outstanding and resulted in the approval of 46 ILRS tracking stations, 4 ILRS Operations Centers, 3 ILRS Analysis Centers, 4 Lunar Analysis Centers, 18 Associate Analysis Centers, 2 Global Data Centers and 1 Regional Data Center. The currently approved ILRS organizations can be found at http://ilrs.gsfc.nasa.gov/about/organization/compmap.html. The Central Bureau was established at the NASA Goddard Space Flight Center with John Bosworth as Director and Michael Pearlman of the Harvard-Smithsonian Center for Astrophysics (CfA) as Secretary. In accordance with the ILRS Terms of Reference, Mr. Bosworth and Dr. Pearlman, along with Prof. Beutler, will serve as ex-officio members of the ILRS Governing Board.


The final CSTG SLR/LLR Subcommission General Assembly and first ILRS General Assembly was held on the evening of 22 September 1998 in conjunction with the 11th International Workshop on Laser Ranging in Deggendorf, Germany. John Degnan, the chairman, officially disbanded the CSTG Satellite and Laser Ranging Subcommission and replaced it with the new International Laser Ranging Service. Power to make policy was simultaneously transferred from the CSTG Subcommission Steering Committee to the newly elected ILRS Governing Board. Like the earlier Subcommission, the ILRS will retain its subordinate affiliation to the CSTG Executive Board as stated in the ILRS Terms of Reference.



The new ILRS Governing Board held its first meeting on 25 September 1998 immediately following the SLR Workshop. In accordance with the Terms of Reference, the GB elected from among its membership a Chairperson as well as Coordinators and Deputy Coordinators for each of the four Standing Committees (SCs). The Governing Board elected John Degnan as ILRS GB Chairperson, Hiroo Kunimori as Missions Coordinator, Ron Noomen as Analysis Coordinator, Werner Gurtner as Networks and Engineering Coordinator, and John Luck as the Data Formats and Procedures Coordinator.

The ILRS benefits from an extensive legacy of prior efforts, including:

  • IAG Permanent Satellite Tracking Networks for Geodesy, Vienna 1991
  • IAU Monitoring of Earth Rotation and Intercomparison of Techniques (MERIT)
    Program 1978-87
  • IAG Commission X on Global and Regional Geodetic Networks (GRGN)
  • IAU Conventional Terrestrial System (COTES) Working Group for geodesy
  • CSTG Working Group on Fundamental Reference and Calibration Network
  • Working group of European Geoscientists for the Establishment of Networks
    for Earth-science Research (WEGENER)
  • Asia Pacific Regional Geodetic Project (APRGP97)
  • Interkosmos Satellite Geodesy Program
  • US National Geodetic Satellite Program
  • Internationale Erdmessung began in 1886 for international cooperation in
    geodesy