PI: Robin Ciardullo, Penn State University, firstname.lastname@example.org
Address: Dep't of Astronomy and Astrophysics, 525 Davey Lab, University Park, PA 16802, USA
CoI: George Jacoby, Giant Megallan Telescope Organization
CoI: John Feldmeier, Youngstown State University
CoI: Kim Herrmann, Lowell Observatory
Title: The Distance to the Antennae Galaxy
Abstract: The Antennae Galaxy (NGC 4038/39) is a key member of the Toomre sequence of merging galaxies, and an important astrophysical laboratory for a host of exotic objects, such as ultra luminous x-ray sources, super star clusters, and tidal dwarf galaxies. Yet the distance to the system is extremely controversial, with recent estimates ranging from 13.3 Mpc (Saviane \etal 2008) to 22.3 Mpc (Schweizer \etal 2008). Since this uncertainty effects all our astrophysical measurements, it is vital that the question be settled. We propose to use the CTIO 4-m telescope to measure the Antennae Galaxy's distance using the Planetary Nebula Luminosity Function. By imaging the galaxy in [O III] (lambda) 5007, H(alpha), and in the continuum, we will be able to produce a definitive distance to this important system. We also note that if the galaxy is closer than ~ 15 Mpc, our survey will produce a large sample of PNe for a future kinematic study. This proposal is a resubmission of program 2009A-0272, which was mostly lost to clouds and extremely poor seeing. Only five hours of marginally useful data were acquired; these observations imply a distance D > 12 Mpc. To place a more interesting limit on the system's distance, more time (with at least close to median seeing!) is needed.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360