Obs. : 2011-06-05 Planet Ly alpha (photons/cm^2/sec) Mercury 4.029e+11 Venus 4.042e+11 Earth 4.271e+11 Mars 4.042e+11 Jupiter 4.109e+11 Saturn 4.016e+11 Uranus 4.169e+11 Neptune 4.166e+11 Pluto 4.271e+11