Obs. : 2018-10-01 Planet Ly alpha (photons/cm^2/sec) Mercury 3.472e+11 Venus 3.500e+11 Earth 3.564e+11 Mars 3.530e+11 Jupiter 3.500e+11 Saturn 3.518e+11 Uranus 3.564e+11 Neptune 3.536e+11 Pluto 3.516e+11