Subaru succeeded in obtaining a precise distance to the most distant cosmic explosion ever seen. Such cosmic explosions, called gamma-ray bursts, are thought to occur when a massive star collapses and creates a black hole. Observations by Subaru and other telescopes on Mauna Kea, Hawaii, were instrumental in showing that this explosion is 500 million light-years more distant than all previously known explosions of its kind. The distance of the explosion, 12.8 billion light-years away, is at the observational frontier of space.

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More info: Subaru telescope web page