Omega Centauri

Omega Centauri is the largest and brightest globular cluster in the Milky Way galaxy. At 100 million light years in diameter, it is certainly a colossal being. However, Globular clusters are in fact quite small in the scheme of the universe. What makes Omega Cen, as it's commonly known, so interesting is its varied composition and the history behind it. There are two different populations of Globular clusters, denoted metal rich and metal poor, but Omega Cen actually has stars of both within its cluster; this begins to articulate its wide and varied history as a denizen of galactic space.

Globular clusters are satellite groups of stars that, although primarily found in a galaxy's center, can also be found in a wide and distant halo around a galaxy; sometimes at distances where no other debris or star systems lie in orbit of that galaxy. Because of their relatively small size, but inherent stability as a single unit, globular clusters are commonly traded between galaxies throughout galactic history; our own galaxy is in the process of stealing two globular clusters from nearby dwarf galaxies. Globular clusters are fascinating to astronomers because, even as galaxies collide and are consumed, these clusters remain relatively unaffected, only keeping bits of their pasts within themselves. Presently the most promising source for an unabridged compendium of the universe are these globular clusters.