Star cluster kinematics in the GAIA era

The GAIA astrometric satellite will measure positions, proper motions and parallaxes of millions of stars with micro-arcsecond accuracy. This will greatly increase our understanding of the stellar populations of the Milky Way and their dynamics. In particular, it will be possible to determine internal and space motions of a large number of open or globular clusters with an accuracy of a few km/s or better, which will bring new insights into the way star clusters evolve and how they and the Milky Way as a whole have formed. It will also be possible to look for clusters which have a common space motion and follow tidal streams from dissolving globular clusters over many orbits by kinematically selecting their members, which will constrain the form of the galactic potential. I illustrate how GAIA will improve our knowledge on the kinematics and dynamics of star clusters and what can be learned by comparing the GAIA data with realistic N-body simulations of star clusters, possible with e.g. future GPU or GRAPE computers. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim