Obs. : 2011-01-05 Planet Ly alpha (photons/cm^2/sec) Mercury 3.607e+11 Venus 3.549e+11 Earth 3.795e+11 Mars 3.732e+11 Jupiter 3.665e+11 Saturn 3.567e+11 Uranus 3.665e+11 Neptune 3.721e+11 Pluto 3.670e+11