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Dynamic Modelling of the Hipparcos Attitude

van Leeuwen, Floor; Fantino, Elena

We present a new method for a high-accuracy reconstruction of the attitude for a slowly spinning satellite. This method, referred to as the fully-dynamic approach, explores the possibility to describe the satellite's attitude as that of a rigid body subject to continuous external torques. The method is tried out on the Hipparcos data and is shown …

A Detailed Analysis of the Operational Orbit of the Hipparcos Satellite

van Leeuwen, Floor; Dalla Torre, Andrea

An analysis of the orbital evolution of the ESA's Hipparcos satellite is presented. Hipparcos operated between August 1989 and March 1993 in a highly elliptical orbit: a geostationary transfer orbit with increased perigee height. The requirements of the scientific mission included high accuracy knowledge of the position and velocity vectors of the…

Modelling the Torques Affecting the Hipparcos Satellite

van Leeuwen, Floor; Fantino, Elena

Reconstructed attitude data for the Hipparcos mission as obtained in the final stages of the data analysis for the published catalogue is used to derive detailed information on the dynamics of the satellite. Most elements of the inertia tensor of the satellite could be calibrated from the observed acceleration data, which are also used to reconstr…

The Operational Environment of the Hipparcos Mission

van Leeuwen, Floor; Penston, Margaret J.

We investigate links between the observational environment as experienced by the Hipparcos satellite and the performance of the spacecraft and payload instrumentation, with particular emphasis on finding out whether some of these effects may have been inadequately represented in instrument calibrations and could thus have affected the scientific r…

Introduction to a Further Examination of the Hipparcos Data

van Leeuwen, Floor; Fantino, Elena

We present an introduction to four papers on further analysis of the raw Hipparcos data. This analysis has lead to the recognition of how orbit, radiation and temperature conditions did or didn't affect the scientific results of the Hipparcos mission. It also led the way to a new reduction of the scientific data that shows from its initial results…