What shines in the gamma-ray sky? This simulated image models the intensities of gamma rays [
http://cossc.gsfc.n…] with over 40 million times the energy of visible light, and represents how the sky might appear to the Gamma-ray Large Area Space Telescope [
http://glast.gsfc.n…] (GLAST) after its first year in orbit. Familiar steady stars are absent from the dramatic 80x80 degree field which looks directly away from the center of the Galaxy. Instead, the Geminga [
http://imagine.gsfc…] and Crab pulsars [
http://oposite.stsc…] - bizarre, spinning stellar corpses known to be neutron stars [
http://antwrp.gsfc.…] - are the two brightest gamma-ray sources. These and other gamma-ray bright objects in the field, monstrous active galaxies [
http://imagine.gsfc…active_galaxies.html ] and still unknown [
http://antwrp.gsfc.…] sources, have been detected by the Energetic Gamma-Ray Experiment Telescope [
http://cossc.gsfc.n…] (EGRET) on the orbiting Compton Gamma-Ray Observatory [
http://cossc.gsfc.n…]. However, most of the simulated sources are new - extrapolating current ideas and anticipating discoveries resulting from GLAST's improved gamma-ray vision [
http://glast.gsfc.n…Anticen/ ]. The central broad band of faint gamma-ray emission is due to high-energy cosmic rays [
http://antwrp.gsfc.…] colliding with interstellar gas in the outer spiral arms of the Milky Way [
http://antwrp.gsfc.…], while below is a diffuse energetic glow from prominent molecular clouds [
http://antwrp.gsfc.…] in Monoceros, Orion, Auriga, and Taurus. Intended to explore [
http://www-glast.so…] extreme environments in the distant cosmos [
http://universe.gsf…] and planned for launch in 2005, GLAST is under development by NASA, U.S., and international partners.
Explanation
What shines in the gamma-ray sky? This simulated image models the intensities of gamma rays [
http://cossc.gsfc.n…] with over 40 million times the energy of visible light, and represents how the sky might appear to the Gamma-ray Large Area Space Telescope [
http://glast.gsfc.n…] (GLAST) after its first year in orbit. Familiar steady stars are absent from the dramatic 80x80 degree field which looks directly away from the center of the Galaxy. Instead, the Geminga [
http://imagine.gsfc…] and Crab pulsars [
http://oposite.stsc…] - bizarre, spinning stellar corpses known to be neutron stars [
http://antwrp.gsfc.…] - are the two brightest gamma-ray sources. These and other gamma-ray bright objects in the field, monstrous active galaxies [
http://imagine.gsfc…active_galaxies.html ] and still unknown [
http://antwrp.gsfc.…] sources, have been detected by the Energetic Gamma-Ray Experiment Telescope [
http://cossc.gsfc.n…] (EGRET) on the orbiting Compton Gamma-Ray Observatory [
http://cossc.gsfc.n…]. However, most of the simulated sources are new - extrapolating current ideas and anticipating discoveries resulting from GLAST's improved gamma-ray vision [
http://glast.gsfc.n…Anticen/ ]. The central broad band of faint gamma-ray emission is due to high-energy cosmic rays [
http://antwrp.gsfc.…] colliding with interstellar gas in the outer spiral arms of the Milky Way [
http://antwrp.gsfc.…], while below is a diffuse energetic glow from prominent molecular clouds [
http://antwrp.gsfc.…] in Monoceros, Orion, Auriga, and Taurus. Intended to explore [
http://www-glast.so…] extreme environments in the distant cosmos [
http://universe.gsf…] and planned for launch in 2005, GLAST is under development by NASA, U.S., and international partners.
Explanation
