Obs. : 2017-02-09 Planet Ly alpha (photons/cm^2/sec) Mercury 3.294e+11 Venus 3.464e+11 Earth 3.279e+11 Mars 3.439e+11 Jupiter 3.148e+11 Saturn 3.196e+11 Uranus 3.439e+11 Neptune 3.494e+11 Pluto 3.234e+11