Survey of the sky at energies above 1 GeV, collected by the Fermi Gamma-ray Space Telescope in five years of observation (2009 to 2013).
(echo:: @ ᯤ)
Survey of the sky at energies above 1 GeV, collected by the Fermi Gamma-ray Space Telescope in five years of observation (2009 to 2013).
(echo:: @ ᯤ)