Obs. : 2010-10-02 Planet Ly alpha (photons/cm^2/sec) Mercury 3.857e+11 Venus 3.852e+11 Earth 3.686e+11 Mars 3.852e+11 Jupiter 3.702e+11 Saturn 3.857e+11 Uranus 3.702e+11 Neptune 3.657e+11 Pluto 3.767e+11