Obs. : 2016-09-01 Planet Ly alpha (photons/cm^2/sec) Mercury 3.894e+11 Venus 3.894e+11 Earth 3.910e+11 Mars 3.813e+11 Jupiter 3.894e+11 Saturn 3.869e+11 Uranus 4.026e+11 Neptune 3.910e+11 Pluto 3.837e+11