... Farther than any known galaxy , quasar , or optical supernova , the gamma-ray burst recorded last week was clocked at redshift 8.2, making it the farthest explosion of any type yet detected . Occurring only 630 million years after the Big Bang , GRB 090423 detonated so early that astronomers had no direct evidence that anything explodable even existed back then. The faint infrared afterglow of GRB 090423 was recovered by large ground telescopes within minutes of being discovered. ...