= Dear colleagues,

We would like to draw your attention to the session “G2.1 Precise Orb= it Determination for Geodesy and Earth Science” organized at the upco= ming General Assembly of the European Geosciences Union, taking place from = April 3-8, 2022. The EGU22 aims to provide an on-site experience again for those attending in-person, while at the same = time introducing new concepts to include virtual attendees as much as possi= ble.

G2.1 session description:

Precise orbit determination is of central importance for many applications = of geodesy and earth science. The challenge is to determine satellite orbit= s in an absolute sense at the centimeter or even sub-centimeter level, and = at the millimeter or even sub-millimeter level in a relative sense. Four constellations of GNSS satellites are avai= lable and numerous position-critical missions (e.g. altimetry, gravity, SAR= and SLR missions) are currently in orbit. Altogether, outstanding data are= available offering new opportunities to push orbit determination to the limit and to explore new applications.<= br>
This session aims to make accessible the technical challenges of orbit dete= rmination and modelling to the wider community and to quantify the nature o= f the impact of dynamics errors on the various applications. Contributions = are solicited from, but not limited to, the following areas: (1) precise orbit determination and validation; (= 2) satellite surface force modelling; (3) advances in modelling atmospheric= density and in atmospheric gravity; (4) advances in modelling earth radiat= ion fluxes and their interaction with space vehicles; (5) analysis of changes in geodetic parameters/earth = models resulting from improved force modelling/orbit determination methods;= (6) improvements in observable modelling for all tracking systems, e.g. SL= R, DORIS, GNSS and their impact on orbit determination; (7) advances in combining the different tracking s= ystems for orbit determination; (8) the impact of improved clock modelling = methods / space clocks on precise orbit determination; (9) advances in mode= lling satellite attitude.

Please consider submitting an abstract to this dedicated orbit session. The= deadline for abstract submission is January 12, 2022 at 13:00 CET. We are = looking forward to your contribution.

On behalf of the convenors of session G2.1, Adrian J=E4ggi

Co-conveners: Alexandre Couhert, Urs Hugentobler, Oliver Montenbruck, Heike= Peter

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