From Wikipedia.org: Omega Centauri (ω Cen), or NGC 5139, is a globular cluster in the constellation of Centaurus that was by Edmond Halley in 1677. Located at a distance of 15,800 light-years (4,850 pc), it is the globular cluster in the Milky at a diameter of roughly 150 light-years. It is estimated to contain approximately 10 million and a total equivalent to 4 million masses.
Omega Centauri is so distinctive from the other globular clusters that it is to have an alternate origin as the core remnant of a disrupted dwarf galaxy.

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