From Wikipedia: "Omega Centauri ( NGC 5139, or Caldwell 80) is a globular cluster in the constellation of Centaurus that was first identified as a non-stellar object by Edmond Halley in...
Formerly thought to be an Sa or maybe Sb galaxy (Shapley-Ames Catalog, 2nd Ed.), this is now known to be a peculiar galaxy with some characteristics of an exponential-type elliptical ga...