Obs. : 2017-07-13 Planet Ly alpha (photons/cm^2/sec) Mercury 3.665e+11 Venus 3.728e+11 Earth 3.862e+11 Mars 3.652e+11 Jupiter 3.794e+11 Saturn 3.862e+11 Uranus 3.791e+11 Neptune 3.833e+11 Pluto 3.879e+11