Obs. : 2015-10-11 Planet Ly alpha (photons/cm^2/sec) Mercury 2.382e+11 Venus 2.441e+11 Earth 2.165e+11 Mars 2.400e+11 Jupiter 2.400e+11 Saturn 2.164e+11 Uranus 2.109e+11 Neptune 2.091e+11 Pluto 2.139e+11