Obs. : 2011-10-08 Planet Ly alpha (photons/cm^2/sec) Mercury 4.182e+11 Venus 4.182e+11 Earth 4.257e+11 Mars 4.189e+11 Jupiter 4.238e+11 Saturn 4.182e+11 Uranus 4.257e+11 Neptune 4.221e+11 Pluto 4.287e+11