Omega Centauri has been known to be an unusual globular cluster for a long time. A new result obtained by Hubble and the Gemini Observatory reveals that the globular cluster may have a rare intermediate-mass black hole hidden in its centre, implying that it is likely not a globular cluster at all, but a dwarf galaxy stripped of its outer stars.
Omega Centauri, the largest and brightest globular cluster in the sky, is visible from Earth with the naked eye and is one of the favourite celestial objects for stargazers from the southern hemisphere. Although 17 000 light-years away, it located just above the plane of the Milky Way and appears almost as large as the full Moon when seen from a dark, rural area.
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