Obs. : 2011-09-03 Planet Ly alpha (photons/cm^2/sec) Mercury 4.370e+11 Venus 4.361e+11 Earth 4.277e+11 Mars 4.395e+11 Jupiter 4.330e+11 Saturn 4.316e+11 Uranus 4.295e+11 Neptune 4.273e+11 Pluto 4.316e+11