The Omega Centauri globular cluster in the constellation of Centaurus. At a distance of 17090 light-years, this is the largest and most massive known globular cluster in the Milky Way.
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Ou4 is located in the constellation Cepheus, embedded within another nebula known as Sh2-129, also called the Flying Bat Nebula. Discovered by the French amateur astronomer Nicolas Outt...