Detection of GRB 090423

Date: April 23, 2009 • Location: Rome, Italy

The gamma-ray burst GRB 090423 was detected coming from the most distant astronomical object of any kind known at the time.

In gamma-ray astronomy, gamma-ray bursts (GRBs) are extremely energetic events occurring in distant galaxies that represent the brightest and most powerful class of explosion in the Universe. These extreme electromagnetic emissions are second only to the Big Bang as the most energetic and luminous phenomena known. Gamma-ray bursts can last from a few milliseconds to several hours. After the initial flash of gamma rays, a longer-lived afterglow is emitted, usually in the longer wavelengths of X-ray, ultraviolet, optical, infrared, microwave or radio frequencies.