Obs. : 2016-05-17 Planet Ly alpha (photons/cm^2/sec) Mercury 4.114e+11 Venus 4.114e+11 Earth 4.121e+11 Mars 4.121e+11 Jupiter 4.108e+11 Saturn 4.124e+11 Uranus 4.086e+11 Neptune 4.146e+11 Pluto 4.165e+11