Detection and measurement of planetary systems with GAIA

¹ The University of Pittsburgh, Department of Physics and Astronomy, Pittsburgh, PA 15260, USA
² Osservatorio Astronomico di Torino, 10025 Pino Torinese, Italy
³ Space Telescope Science Institute, Baltimore, MD 21218, USA

Corresponding author: A. Sozzetti, alex@phyast.pitt.edu

Received: 8 January 2001
Accepted: 27 April 2001

Abstract

We use detailed numerical simulations and the υ Andromedæplanetary system as a template to evaluate the capability of the ESA Cornerstone Mission GAIA in detecting and measuring multiple planets around solar-type stars in the neighborhood of the Solar System. For the outer two planets of the υ Andromedæsystem, GAIA high-precision global astrometric measurements would provide estimates of the full set of orbital elements and masses accurate to better than 1-10% , and would be capable of addressing the coplanarity issue by determining the true geometry of the system with uncertainties of order of a few degrees. Finally, we discuss the generalization to a variety of configurations of potential planetary systems in the solar neighborhood for which GAIA could provide accurate measurements of unique value for the science of extra-solar planets.