Obs. : 2017-07-09 Planet Ly alpha (photons/cm^2/sec) Mercury 3.660e+11 Venus 3.591e+11 Earth 3.724e+11 Mars 3.596e+11 Jupiter 3.793e+11 Saturn 3.724e+11 Uranus 3.537e+11 Neptune 3.606e+11 Pluto 3.712e+11