Obs. : 2010-07-14 Planet Ly alpha (photons/cm^2/sec) Mercury 3.928e+11 Venus 3.887e+11 Earth 3.927e+11 Mars 3.931e+11 Jupiter 3.846e+11 Saturn 3.960e+11 Uranus 3.846e+11 Neptune 3.878e+11 Pluto 3.960e+11