Max-Planck-Institut
  für extraterrestrische Physik

On 2008 Sept. 17, 31.7 hours after GRB 080916C exploded, the MPE Gamma-Ray Burst Optical/Near-Infrared Detector (GROND) on the 2.2m Max Planck Telescope at the European Southern Observatory, La Silla, Chile, began acquiring images of the blast's fading afterglow (circled).

Image: MPE / GROND

NASA'S FERMI TELESCOPE SEES MOST EXTREME GAMMA-RAY BLAST YET

The first gamma-ray burst to be seen with substantial GeV emission from NASA's Fermi Gamma-ray Space Telescope is one for the record books. The blast had the greatest total energy, the fastest motions and the highest-energy initial emissions ever seen.
This explosion, designated GRB 080916C, occurred at 0:13 UT on 2008 Sept. 16, in the constellation Carina. Fermi's other instrument, the Gamma-ray Burst Monitor, simultaneously recorded the event. Together, the two instruments provide a view of the blast's initial, or prompt, gamma-ray emission from energies between 3,000 to more than 5 billion times that of visible light.
Nearly 32 hours after the blast, Jochen Greiner of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, led a group that searched for the explosion's fading afterglow. The team simultaneously captured the field in seven wavelength bands using the MPE built and operated detector GROND.
In certain colors, the brightness of a distant object shows a characteristic drop-off caused by intervening gas clouds. The farther away the object is, the redder the wavelength where this fade-out occurs. This gives astronomers a quick estimate of the object's distance. The team's follow-up observations established that the explosion took place 12.2 billion light-years away.
"Already, this was an exciting burst," said Julie McEnery, a Fermi deputy project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "But with the GROND team's distance, it went from exciting to extraordinary."

The Fermi team's results appeared for the first time on February 19, 2009 in the online edition of the journal Science.
The GROND results will be published in Astronomy & Astrophysics.

	Fermi / NASA press release
	Original article in Science Express
	GROND results preprint