Obs. : 2010-11-26 Planet Ly alpha (photons/cm^2/sec) Mercury 3.850e+11 Venus 3.721e+11 Earth 3.712e+11 Mars 3.850e+11 Jupiter 3.721e+11 Saturn 3.708e+11 Uranus 3.721e+11 Neptune 3.783e+11 Pluto 3.850e+11