Obs. : 2011-08-10 Planet Ly alpha (photons/cm^2/sec) Mercury 3.909e+11 Venus 3.924e+11 Earth 3.933e+11 Mars 3.957e+11 Jupiter 3.932e+11 Saturn 3.982e+11 Uranus 3.865e+11 Neptune 3.891e+11 Pluto 3.954e+11