Obs. : 2011-07-26 Planet Ly alpha (photons/cm^2/sec) Mercury 3.737e+11 Venus 3.992e+11 Earth 4.020e+11 Mars 4.052e+11 Jupiter 4.049e+11 Saturn 3.901e+11 Uranus 3.946e+11 Neptune 3.982e+11 Pluto 4.043e+11