Obs. : 2017-06-26 Planet Ly alpha (photons/cm^2/sec) Mercury 3.635e+11 Venus 3.652e+11 Earth 3.611e+11 Mars 3.635e+11 Jupiter 3.666e+11 Saturn 3.584e+11 Uranus 3.606e+11 Neptune 3.537e+11 Pluto 3.570e+11