Obs. : 2015-05-21 Planet Ly alpha (photons/cm^2/sec) Mercury 4.669e+11 Venus 4.840e+11 Earth 4.486e+11 Mars 4.669e+11 Jupiter 4.865e+11 Saturn 4.486e+11 Uranus 4.485e+11 Neptune 4.306e+11 Pluto 4.349e+11