This ‘Galaxy That Wasn’t’ Never Bore Any Stars

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By Katrina Miller, The New York Times. 

Excerpt: This week, astronomers announced the discovery of a new kind of cosmic object, something that is very nearly a galaxy, save for one crucial, missing ingredient: stars. The almost-galaxy is about 14 million light-years from Earth. It was the ninth cloud found to be associated with a nearby spiral galaxy, leading to its serendipitous name: Cloud-9. The object is starless, consisting of only a haze of hydrogen gas that astronomers believe is swaddled in a much more massive clump of dark matter, the invisible substance that permeates the cosmos and shapes its overarching structure. ...Cloud-9 is the first confirmed example of what astronomers call a RELHIC, short for Reionization-Limited H I Cloud and pronounced “relic.” Such objects are rich in gaseous hydrogen but devoid of any stars. They are failed galaxies thought to be nearly as old as time itself, primordial fossils that can help astronomers understand the conditions required for galaxies to grow.... 

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