The Second Nucleus of NGC 7727: Direct Evidence for the Formation and Evolution of an Ultracompact Dwarf Galaxy

  title={The Second Nucleus of NGC 7727: Direct Evidence for the Formation and Evolution of an Ultracompact Dwarf Galaxy},
  author={François Schweizer and Patrick Seitzer and Bradley C. Whitmore and Daniel D. Kelson and Edward V. Villanueva},
  journal={The Astrophysical Journal},
We present new observations of the late-stage merger galaxy NGC 7727, including Hubble Space Telescope/WFPC2 images and long-slit spectra obtained with the Clay telescope. NGC 7727 is relatively luminous ( = −21.7) and features two unequal tidal tails, various bluish arcs and star clusters, and two bright nuclei 480 pc apart in projection. These two nuclei have nearly identical redshifts, yet are strikingly different. The primary nucleus, hereafter Nucleus 1, fits smoothly into the central… 

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