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NGC 5139 - Omega Centauri (29th Apr 2025)

Globular Cluster in Centaurus

Omega Centauri is a globular cluster in the constellation of Centaurus that was first identified as a non-stellar object by Edmond Halley in 1677. Located at a distance of 17,090 light-years, it is the largest known globular cluster in the Milky Way at a diameter of roughly 150 light-years. It is estimated to contain approximately 10 million stars, with a total mass of 4 million solar masses, making it the most massive known globular cluster in the Milky Way.

Its immense age of 16 billion years makes it one of the most ancient objects in the universe. Aside from its impressive size and brilliance, Omega has attracted attention for the complexity of its stellar populations. Differing populations of stars may be accounted for by mergers and captures of
stars during the immense history of Omega.