Obs. : 2011-03-27 Planet Ly alpha (photons/cm^2/sec) Mercury 4.207e+11 Venus 3.647e+11 Earth 4.242e+11 Mars 3.846e+11 Jupiter 4.091e+11 Saturn 4.037e+11 Uranus 3.846e+11 Neptune 3.647e+11 Pluto 3.601e+11