Omega Centauri, also designated as NGC 5139, was unusual among known globular clusters. For one thing, it was one of the largest known—the largest globular of all such in Earth’s galaxy, and second only to the Andromeda’s Mayall II in the entire local group of galaxies. It was one of very few globulars actually visible to the naked eye, appearing as a fuzzy patch in the skies of Earth’s southern hemisphere just 17 degrees northeast of the brilliant and relatively nearby Alpha Centauri. Normally, it was visible from Earth as a fuzzy, third-magnitude star. When viewed in an absolutely black
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