GRB 090423: The Farthest Explosion Yet Measured
Credit: Gemini Observatory / NSF / AURA, D. Fox & A. Cucchiara (Penn State U.), and E. Berger (Harvard Univ.)
Explanation: An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation by NASA’s orbiting Swift Observatory. Farther than any known galaxy, quasar, or optical supernova, the gamma-ray burst recorded was clocked at redshift 8.2, making it the farthest explosion of any type yet detected.
