new icn messageflickr-free-ic3d pan white
The FERMI gamma-ray sky map - in COLOR | by LLacertae
Back to photostream

The FERMI gamma-ray sky map - in COLOR

The FERMI Space Telescope observes the whole sky in every 6 hours. With its instrument called LAT, it sees the sky in its most energetic appearence: gamma-rays. LAT detects photons at an energy of 20 MeV to over 300 GeV. Gamma-ray are producers in: pulsars, active galactic nuclei, globular clusters, cosmic-ray electrons, gamma-ray bursts, binary stars and supernova remnants. The used data for the maps have been provided by Douglas Finkbeiner and Gregory Dobler. The team studied the diffuse glow of the sky at high energies (arXiv:0910.4583 and arXiv:1005.5480v1), as well as they concluded the existence of a hourglass-shaped, bipolar bubble, extending from the galaxy's center. My aim was to create an whole sky, 360° * 180° map of the sky in the pseudocolors of gamma-ray emission. This RGB visual consists of 12 individual pictures of different photon energies. Lowest energies (300 MeV) are in red, highest energies (300 GeV) are encoded in blue. Green areas represent photons at the edge of softer energies, towards the hard and randomly scattered "blue" radiation. The luminosity correlates with the intensity of the particular photon energy range.

Please notice the mostly greenish, bipolar structure, extending from the center of the disc. At mid-energies (from 1 GeV to 30 GeV), the gamma-ray emission lines up with two large bubbles, which seem to originate at the galactic center. A correlation with other wavelenghts, such as ROSAT x-ray and WMAP microwave, is persistent. The origin is still unknown, but two possibilities have been postulated. (1) Matter injection onto the central suppermassive black hole (SMBH). This process goes in tandem with the developement of magnetic jets, which would have had "blowed" the bubbles. (2) Strong nuclear starburst in the past 10 million years.

2 faves
Taken on August 8, 2010