Obs. : 2014-08-04 Planet Ly alpha (photons/cm^2/sec) Mercury 3.198e+11 Venus 3.360e+11 Earth 3.931e+11 Mars 3.410e+11 Jupiter 3.198e+11 Saturn 3.461e+11 Uranus 3.879e+11 Neptune 3.971e+11 Pluto 3.820e+11