Obs. : 2014-10-15 Planet Ly alpha (photons/cm^2/sec) Mercury 3.804e+11 Venus 3.819e+11 Earth 3.653e+11 Mars 3.774e+11 Jupiter 3.943e+11 Saturn 3.814e+11 Uranus 3.539e+11 Neptune 3.658e+11 Pluto 3.745e+11