Analysis of the HIPPARCOS Measurements of upsilon Andromedae: A Mass Estimate of Its Outermost Known Planetary Companion
Mazeh, Tsevi; van Leeuwen, Floor; Zucker, Shay; Dalla Torre, Andrea
Israel, United Kingdom, Italy
Abstract
We present an analysis of Hipparcos astrometric measurements of υ Andromedae, a nearby main-sequence star around which three planet candidates have recently been discovered by means of radial velocity measurements. The stellar orbit associated with the outermost candidate has a period of 1269+/-9 days and a minimum semimajor axis of 0.6 mas. Using the Hipparcos data together with the spectroscopic elements, we found a semimajor axis of 1.4+/-0.6 mas. This implies a mass of 10.1+4.7-4.6 Jupiter masses for that planet of υ And.