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Detection and measurement of planetary systems with GAIA

A. Sozzetti·S. Casertano·M. G. Lattanzi·A. Spagna
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Abstract

We use detailed numerical simulations and the $\upsilon$ Andromedae, planetary 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 $\upsilon$ Andromedae, system, 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.

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A. Sozzetti, S. Casertano, M. G. Lattanzi, A. Spagna. 2001-04-24. Detection and measurement of planetary systems with GAIA. https://doi.org/10.1051/0004-6361%3A20010788

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