Obs. : 2012-03-11 Planet Ly alpha (photons/cm^2/sec) Mercury 4.469e+11 Venus 4.283e+11 Earth 4.227e+11 Mars 4.227e+11 Jupiter 4.283e+11 Saturn 4.271e+11 Uranus 4.469e+11 Neptune 4.535e+11 Pluto 4.474e+11