Bright stars may dazzle us, but it's the faint ones that test an astronomer's skill. After all, they're the hardest to detect, making their discovery a greater achievement. Now researchers report that a newfound star cluster  in the constellation Pegasus is the dimmest ever seen . Whereas the Milky Way's greatest star clusters radiate millions of times more light than the sun, Segue 3, shown here in an image spanning 64 light-years, ekes out a mere 90 suns' worth of light. As astronomers will report in a future issue of The Astronomical Journal, the dim cluster is ancient, having formed 12 billion years ago. Located 55,000 light-years from Earth and 22,000 light-years below our galaxy's plane, Segue 3 resides in the Milky Way's halo, the population of old stars that surrounds the spiral-sculpted disk housing the sun. The cluster has cast most of its original stars into the halo and is destined to disintegrate completely.
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