Get your gamma-ray goggles on April 6, 2009Posted by Sarah in new astronomy, science, space.
Tags: astronomy, fermi, grb, nasa
As one of its contributiosn to the Around the World in 80 Telescopes webcast, part of the 100 Hours of Astronomy fiesta last weekend, NASA released a great set of movies made from data gathered by the Fermi gamma-ray observatory. It shows a view of the full sky at gamma-ray wavelengths taken between August and October last year, with gamma ray bursts popping up in quick flashes. Very nice!
Gamma ray bursts, or GRBs for short, are short flashes of gamma rays lasting typically from around a second to several minutes. So when one is spotted by one of several orbiting gamma-ray observatories, time is of the essence and astronomers rush to get a ground-based telescope aimed at the direction of the burst to gather as much information as possible on its underlying cause. Astronomers have suggested a number of progenitors for these fascinating events, such as the rapid collapse of very low-metallicity rotating stars (‘collapsars’), but as no two bursts seem to display the same behaviour it’s difficult to come up with a model that is consistent with all the observations.
What is known, is that the majority of GRBs take place at high redshift, in the very early Universe. The energy released in GRBs is staggeringly huge: just last year, a burst recorded by Fermi was calculated to have the energy of 9,000 supernovae!
Read here for a full explanation of what the animations show and links to further information on GRBs, and click on the image for a full-size animation.
Image: NASA/DOE/Fermi LAT Collaboration