1. McGill University Space Institute, 3550 Rue University, Montreal, QC H3A 2A7, Canada
2. York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
3. Department of Astronomy and Astrophysics, University of Toronto, 50 St George St, Toronto, ON M5S 3H4, Canada
4. Australian Astronomical Observatory, PO Box 915, North Ryde, NSW 1670, Australia
5. Department of Physics and Astronomy, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, USA
6. Centre for Astrophysics Research, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, UK
7. Physics Astrophysics Building, Stanford University, 452 Lomita Mall, Stanford, CA 94305-4085, USA
8. California Institute of Technology, Pasadena, CA 91125, USA