Continuation of An Astrometric Search for Planetary Companions to Proxima Centauri

We propose to extend our astrometric monitoring of Proxima Centauri by acquiring ten additional measurement sets during Cycle 6. These observations will further reduce the upper mass limit of undetected planets for periods of less than 600 days. They will reduce the probability of false positive detection for a suspected perturbation with a period near 80 days. The Proxima Cen observations will be combined with results from an ongoing radial velocity monitoring program. As of 9/95 radial velocities suggest a perturbation with a period near 90 days. If real, the astrometric and radial velocity perturbations could be due to a gas giant planet orbiting Proxima Centauri, potentially one of the most exciting discoveries to be made in astronomy. The combined Cycle 6 astrometry and additional velocity data will allow us to determine the inclination of the planetary system and a mass for the planet.