Obs. : 2014-07-15 Planet Ly alpha (photons/cm^2/sec) Mercury 4.562e+11 Venus 4.562e+11 Earth 3.671e+11 Mars 3.583e+11 Jupiter 4.343e+11 Saturn 3.593e+11 Uranus 4.269e+11 Neptune 3.842e+11 Pluto 3.638e+11