Obs. : 2014-09-22 Planet Ly alpha (photons/cm^2/sec) Mercury 4.103e+11 Venus 4.192e+11 Earth 4.049e+11 Mars 3.960e+11 Jupiter 4.308e+11 Saturn 4.020e+11 Uranus 4.049e+11 Neptune 3.938e+11 Pluto 3.918e+11