Astronomers spot two black holes in an orbital dance

Black holes, as frighteningly extreme as they may be, are relatively commonplace across the universe. Like most large galaxies, our own Milky Way packs a supermassive black hole at its core, a lurking monster some four million times as massive as the sun.But our own neighborhood bully appears relatively tame next to a distant quasar, or bright galactic center, recently spotted by astronomers Todd Boroson and Tod Lauer of the National Optical Astronomy Observatory (NOAO) in Tucson, Ariz. The quasar, known as SDSS J153636.22+044127.0, appears to host a pair of black holes, bound together in a tight orbital relationship, circling each other every 100 or so years.

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