Obs. : 2012-07-02 Planet Ly alpha (photons/cm^2/sec) Mercury 4.386e+11 Venus 4.238e+11 Earth 4.454e+11 Mars 4.806e+11 Jupiter 4.238e+11 Saturn 4.785e+11 Uranus 4.218e+11 Neptune 4.283e+11 Pluto 4.469e+11