Luminosity of large amplitude variable stars: Comparison between ground-based predictions and observations by the Hipparcos satellite

Abstract

Since November 1989, the HIPPARCOS satellite has been observing stars in order to fulfil its mission goals. The complete data processing of these observations will take many years to perform. A small group of stars, namely the large amplitude variables, must be processed much closer to real-time so that the luminosity ephemeris can be updated where necessary. This has been achieved by special processing of a subset of the observations of these objects at the European Space Operations Centre (ESOC) and Montpellier University.