****************************************************************************** dorismail 21-Apr-2021 08:05:26 Message No 1273 ****************************************************************************** Author: Soudarin Laurent Subject: IAG 2021, Session 1.5 on improving consistency between TRF, CRF and Please find below an announcement from the IERS Analysis Coordinator. ------------------------------------------------------------------------------------------------ Dear Colleagues As you know the IAG Scientific Assembly will soon take place from 2021 June 28th to July 2nd. The website of the event is available at http://www.iag2021.com/en/web/index/ . The abstract submission deadline approaches quickly. It is April 30th. We, the session conveners of Session 1.5, would like to draw your attention to the session "Comparison and combination of space geodesy techniques for improving consistency between TRF, CRF and EOPs". The full session description is displayed below. We are looking forward receiving your abstracts and apologize for multiple postings. Best regards, Robert Heinkelmann, Chengli Huang, Zinovy Malkin and Manuela Seitz ****** Symposium 1, Session 5 Comparison and combination of space geodesy techniques for improving consistency between TRF, CRF and EOPs The international terrestrial and celestial reference frames, ITRF and ICRF, respectively, as well as the link between them expressed by the Earth Orientation Parameters (EOP) are key products of geodesy and astrometry. Many scientific and practical applications rely on the consistency of ITRF, ICRF, and EOP, and the requirements to all the components of this triad with respect to accuracy, precision and consistency grow steadily. Today, ITRF and ICRF are computed separately, but are linked by cross-alignments or by fixing parameters. While the ITRF and consistently estimated EOP series are derived from a combination of the four space geodetic techniques VLBI, SLR, GNSS and DORIS, the ICRF and the related EOP series are derived from VLBI observations only. To reach a high consistency between the products, the homogeneity of geophysical and astronomical models, of geodetic datum, and of parameterization is necessary. The topics discussed in this session will include the comparison and combination of EOP and TRF solutions derived by different techniques, as well as comparison of VLBI-only and multi-technique CRF realizations including assessing and understanding the systematic differences between them, and their impact on EOP estimates. A further important discussion topic will be issues currently preventing the realization of the terrestrial and celestial reference systems at the mm/μas level of accuracy, such as deficiencies of the station network including station instabilities, technological (precision) limitations of existing techniques, incompleteness of the theory and models, not fully understood and agreed-upon details of the processing strategy, and others. The session solicits contributions to all these topics. This session solicits contributions focusing on the following aspects: Comparison and combination of EOP solutions by different techniques. Comparison and combination of TRF solutions derived by different techniques. Comparison of VLBI-based and combined multi-technique CRF realizations. Unification of astronomical and geophysical modeling. Keywords: Terrestrial Reference Frame (TRF), Celestial Reference Frame (CRF), Earth Orientation Parameters (EOPs), space geodetic techniques, VLBI, multi-technique CRF realization. Please do not reply directly to this message, but send comments and suggestions to IDS.central.bureau@cls.fr