Compton Gamma-Ray Observatory (CGRO) - HEASARC The Compton Gamma-Ray Observatory (CGRO) was launched on April 5, 1991. The second of NASA’s great observatories, CGRO has four instruments that cover an unprecedented six orders of magnitude in energy, from 30 keV to 30 GeV.
| Fermi Gamma-ray Space Telescope NASA"s Fermi Gamma-ray Space Telescope is a powerful space observatory that opens a wide window on the universe of gamma rays, the most energetic form of light.
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