Credit: EGRET Team/NASA/Honeywell Max Q Digital Group, Angela Cheyunski
Mysterious Radiant Sources
Probably the most mysterious way to view the sky is in gamma-rays. Gamma
rays are the most energetic form of electromagnetic radiation, and it takes
extraordinary processes to generate them. Powerful explosions (like those
produced when a star falls into a black hole, or 2 neutron stars collide,
or when a matter cloud collides with an anti-matter cloud) can produce
gamma rays, but such sources only shine for a brief period, then fade. Some
sources emit gamma rays all the time. How these sources do this is not
entirely known, though it probably involves very strong magnetic fields or
extremely powerful shocks. The EGRET detector on the
Compton Gamma Ray Observatory
produced the best map of the gamma ray sources in the universe. The image
above is the EGRET gamma ray source map, in which the bright areas are the
271 gamma-ray emitting objects seen by EGRET. This map is in Galactic
coordinates, which means that the center of the Milky Way is at the center
of the image, and the disk of the Galaxy runs along the center of the
image, right to left. This false color image shows the brightness of the
gamma ray sources seen by EGRET; large white objects glow more brightly in
gamma rays than small orange ones.
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Page Author: Dr. Michael F.
Corcoran
Last modified August 7, 2000
