| Date: | 2010-07-06 09:06:00 | |
| Sender: | Harald Schuh, harald.schuh@tuwien.ac.at <###FROM###> | |
| Subject: | [SLR-Mail] No. 1883: REFAG | |
| Author: | Harald Schuh, harald.schuh | |
| Content: | ******************************************************************************** SLR Electronic Mail 2010-07-06 09:06:00 UTC Message No. 1883 ******************************************************************************** Author: Harald Schuh, harald.schuh@tuwien.ac.at Subject: REFAG Dear Colleagues, We would like to draw your attention to the Session 4, Interaction of Celestial and Terrestrial Reference Frames, a part of the IAG Commission 1 Symposium 2010 on Reference Frames for Applications in Geosciences (REFAG2010) which will be held at Marne la Vallee, France on 4-8 October 2010 Session description: The main objective of this session is the study of the interactions between the celestial and the terrestrial reference frames (CRF and TRF) with a special focus on the consistency between the frames. This covers theoretical aspects of the celestial reference system and systematic effects in the CRF determination. The celestial and the terrestrial ephemeris origin replaced in 2003 the vernal equinox and the traditional first axis of the terrestrial intermediate frame. Consequently, the Earth rotation angle replaced the apparent sidereal time. The Earth orientation parameters (EOP) connect the CRF and the TRF. Some effects or modelling errors which can be expressed in both frames, e.g. atmospheric gradients, can systematically affect each of the frames. Other effects affect only one frame directly but - if not modelled there correctly - can still be transcribed as deformation of the other frame or change of the Earth orientation parameters. W.r.t. theory the effects of the most recent IAU definitions (2006), the relation between the barycentric system (as realized by VLBI) and the geocentric system shall be studied. Additionally, effects which systematically affect source positions are to be identified. This includes the comparison of various CRF realizations, effects of geodetic datum definition on VLBI-determined CRF, effects of meteorological data on VLBI-determined CRF, and effects of various analysis options on VLBI-determined CRF. As for the celestial reference frames the second realization of the ICRF was approved at the XXVIIth IAU General Assembly in 2009. First survey of the new ICRF-2 will be reported. Concerning highly precise optical celestial reference frames, upcoming optical astrometry space missions such as GAIA (Global Astrometry Interferometer for Astrophysics) and SIM (Space Interferometer Mission) will significantly enhance the quality of the optical catalogues in terms of position precision and number of stars. Finally, the interaction between the celestial and terrestrial reference frame and the transformation between both shall be studied with the goal to improve the consistency between celestial reference frames, a terrestrial reference frame and the EOP. This includes the effect of errors in the CRF on the terrestrial reference frame and vise versa, the realization of the NNR-condition for the ITRF (e.g. the influence of deformations). The interaction between the frames and the EOP determination, the effect of various geophysical models, and the interaction with the gravity field can also be reported. --------------------------- Please consider submitting a paper for this session or contact us directly if you have any questions. Please note the submission deadline 31 July, and the registrtation deadline 31 August. More details on REFAG2010 can be found at the meeting Web page http://iag.ensg.ign.fr/index.php?id=140 Looking forward to seeing you in Paris, Session conveners: Harald Schuh, harald.schuh@tuwien.ac.at Sebastien Lambert, sebastien.lambert@obspm.fr Chopo Ma, chopo.ma@mail.nasa.gov Zinovy Malkin, malkin@gao.spb.ru ******************************************************************************** |