1. Department of Astronomy, Harvard University, 60 Garden Street, Cambridge, MA 02138, USA
2. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
3. William H. Miller III Department of Physics & Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
4. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
5. Whitin Observatory, Department of Astronomy, Wellesley College, Wellesley, Massachusetts, USA