Obs. : 2013-03-02 Planet Ly alpha (photons/cm^2/sec) Mercury 4.086e+11 Venus 3.958e+11 Earth 4.215e+11 Mars 4.086e+11 Jupiter 4.272e+11 Saturn 3.954e+11 Uranus 4.142e+11 Neptune 3.958e+11 Pluto 3.874e+11