... Credit Copyright: International Fermi Large Area Telescope Collaboration , NASA , DOE Explanation: For an Earth-orbiting gamma-ray telescope, Earth is actually the brightest source of gamma-rays , the most energetic form of light. ... While that interaction blocks harmful radiation from reaching the surface, those gamma-rays dominate in this remarkable Earth and sky view from the orbiting Fermi Gamma-ray Space Telescope's Large Area Telescope. ... Publications with keywords: Milky Way - atmosphere ....