Fermi Records Extreme Gamma-Ray Burst

The Fermi Gamma-ray Space Telescope, which was formerly known as the Gamma-ray Large Area Space Telescope (GLAST), has recently recorded one of the most massive and extreme gamma-ray bursts in history. The emission was so large, that it even made scientists raise some new questions about this type of events, which they thought they had figured out by then. The newly-observed burst also had the fastest motion ever caught by Earth- or space-based observatories.

“Burst emissions at these energies are still poorly understood, and Fermi is giving us the tools to figure them out,” Peter Michelson, the main investigator at the Large Area Telescope and also a Stanford University physics professor affiliated with the SLAC National Accelerator Laboratory belonging to the Department of Energy (DOE), explains.

“Already, this was an exciting burst. But with the GROND team's distance, it went from exciting to extraordinary,” Fermi deputy project scientist Julie McEnery, who works at NASA's Goddard Space Flight Center in Greenbelt, Maryland, adds.

GRB 080916C is the name given to the celestial event, which was simultaneously recorded by the Gamma-ray Burst Monitor (GBM) and the Large Area Telescope instruments, at approximately 7:13 pm EDT (0013 GMT), in the night of September 15/16, 2008. According to the readings, the emission's energy was between 3,000 to 5 billion times that usually emitted by visible light, which definitely makes this burst that took place in the Carina constellation one of the most spectacular ever discovered.

The European Southern Observatory (ESO), located in La Silla, Chile, has also identified the gamma-rays, by using the Gamma-Ray Burst Optical/Near-Infrared Detector (GROND) instrument, on its 2.2-meter telescope. ESO's team of scientists, led by Max Planck Institute for Extraterrestrial Physics expert Jochen Greiner, has managed to establish that the blast has taken place more than 12.2 billion light-years away, so the danger for Earth is negligible.

“This one burst raises all sorts of questions. In a few years, we'll have a fairly good sample of bursts, and may have some answers,” Michelson explains. The new study detailing the readings appeared in the February 19th issue of the journal Science Express.