... Explanation: An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory . 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 . ... Publications with keywords: gamma-ray burst - redshift - early universe . ... Building Galaxies in the Early Universe . ...