Subject: [SLR-Mail] No. 990: EGS/AGU/EUG Session on Surface Forces and Rotational Dynamics From: Remko Scharroo (remko@deos.tudelft.nl) > ******************************************************************************** SLR Electronic Mail 2002-10-28 12:06:00 UTC Message No. 990 ******************************************************************************** Author: Remko Scharroo (remko@deos.tudelft.nl) Subject: EGS/AGU/EUG Session on Surface Forces and Rotational Dynamics Dear Colleagues, The web pages and session descriptions for the EGS/AGU/EGU Joint Assembly in Nice, France, 6-11 April 2003 is now on-line on: http://www.copernicus.org/egsagueug/ We would particularly like to draw your attention to Session G16 ”Satellite Surface Forces and Satellite Rotational Dynamics”. The description of the session is attached below. Note the various deadlines for registration and abstract submission: - Deadline for Support Application: 1 December 2002 - Deadline for ”Early Bird” Registration: 31 December 2002 - Deadline for Receipt of Abstracts: 15 January 2003 - Deadline for Pre-Registration: 7 March 2003 So remember to submit your abstract no later than 15 January. Best regards, and hoping to see you in Nice in April, Remko Scharroo (convener) Douglas Currie, Frank Lemoine (co-conveners) (PS: Excuse us if you receive this mail through various channels) ---- G16 Satellite Surface Forces and Satellite Rotational Dynamics (co-sponsored by GI) While gravity models are rapidly improving, surface forces are becoming the largest source of satellite orbit errors for a large range of orbital altitudes. For low-flying satellites atmospheric drag is not only a significant force, it is also difficult to model. Deficiencies in drag modelling are the result of uncertainties in the density and composition of the atmosphere, the interaction between the atmospheric particles and the satellite surface, and motion of the atmosphere. Particularly during periods of high solar activity, the density and composition of the atmosphere at the satellite altitude can vary rapidly, to as much as an order of magnitude within a few hours. For satellites in higher orbits, drag becomes less important, while solar radiation pressure becomes increasingly important compared to gravity. The major source of uncertainty in radiation pressure modelling are the reflective properties of the satellite surface, and, for satellites without attitude control and monitoring, the attitude. In the case of LAGEOS I and II, significant advances have been made recently to model the attitude, with important implications for the surface force modelling. Because of their close interaction, both satellite surface forces and rotational dynamics are the topic of this session. We particularly welcome papers dealing jointly with both subjects. Encouraged are also submissions dealing with new methods for modelling of atmospheric drag, the interaction between particles or photons and the satellite surface, the dependence on solar activity, modelling of Earth albedo, and despin and spin axis orientation of geodetic satellites. Event Information While gravity models are rapidly improving, surface forces are becoming the largest source of satellite orbit errors for a large range of orbital altitudes. For low-flying satellites atmospheric drag is not only a significant force, it is also difficult to model. Deficiencies in drag modelling are the result of uncertainties in the density and composition of the atmosphere, the interaction between the atmospheric particles and the satellite surface, and motion of the atmosphere. Particularly during periods of high solar activity, the density and composition of the atmosphere at the satellite altitude can vary rapidly, to as much as an order of magnitude within a few hours. For satellites in higher orbits, drag becomes less important, while solar radiation pressure becomes increasingly important compared to gravity. The major source of uncertainty in radiation pressure modelling are the reflective properties of the satellite surface, and, for satellites without attitude control and monitoring, the attitude. In the case of LAGEOS I and II, significant advances have been made recently to model the attitude, with important implications for the surface force modelling. Because of their close interaction, both satellite surface forces and rotational dynamics are the topic of this session. We particularly welcome papers dealing jointly with both subjects. Encouraged are also submissions dealing with new methods for modelling of atmospheric drag, the interaction between particles or photons and the satellite surface, the dependence on solar activity, modelling of Earth albedo, and despin and spin axis orientation of geodetic satellites. From: EDC slrmail account ********************************************************************************