Obs. : 2014-07-25 Planet Ly alpha (photons/cm^2/sec) Mercury 3.627e+11 Venus 3.529e+11 Earth 3.749e+11 Mars 4.279e+11 Jupiter 3.627e+11 Saturn 4.206e+11 Uranus 3.179e+11 Neptune 3.274e+11 Pluto 3.749e+11