London - BBC - The Fermi space telescope has updated its catalogue of the Universe’s most violent neighbourhoods. Fermi catches gamma rays, the most energetic light, spewing from nature’s most extreme physical processes.
The new catalogue, posted on the Arxiv server, lists the sources of the highest-energy gamma rays that Fermi has yet seen: 514 of them. Some 65 of them are “unassociated” sources that may turn out to be completely new astronomical objects.
The catalogue is to be published in the Astrophysical Journal. It will help outline which of the known sources of other kinds of electromagnetic radiation - such as visible light, or radio waves, or X-rays - are also emitting at this higher range of gamma-ray energies.
That will help astrophysicists unpick exactly what is happening in these violent corners of the cosmos, where processes are going on that we will never be able to mimic in Earth-bound laboratories.
Fermi scans in every direction, gathering gamma rays from the whole cosmos every three hours.
The “all-sky map” accompanying the publication represents all of the gamma-ray detections above 10 gigaelectronvolts that the Fermi telescope has seen in three years’ worth of data.
The prior catalogues produced by Fermi contain literally thousands of gamma-ray emitters in the far-flung cosmos, corresponding to objects such as blazars and active galactic nuclei - both associated with black holes snacking at the centres of galaxies - or pulsars, fast-spinning neutron stars that flash our neighbourhood like a distant lighthouse.