A VLBI Resolution of the Pleiades Distance Controversy.

University Of California-San Diego, La Jolla CA

Investigators

Abstract

The Pleiades is the best studied open star cluster in the sky. It is one of the primary open clusters used to define the "Zero Age Main Sequence" and hence it serves as a cornerstone for programs which use main-sequence fitting to derive distances to other clusters in the Milky Way Galaxy. This role is called into question by the "Pleiades distance controversy"; the distance to the Pleiades from the Hipparcos space astrometry mission of about 120 pc is significantly different from the distance of 133 pc derived from other techniques. In order to resolve this issue, the PI will use Very Long Baseline Interferometry (VLBI) to derive a new, independent trigonometric parallax distance to the Pleiades. He will complete all VLBI measurements for the sample of ten Pleiads and any necessary auxiliary measurements with optical and infrared telescopes. With the completion of this project the Pleiades distance controversy will be resolved, solidifying the use of the Pleiades in determining Galactic structure. In lockstep, the PI will launch a multi-faceted education program that is aimed at the recruitment, retention, and advancement of minority groups in science, technology, engineering, and mathematics.