Obs. : 2018-01-06 Planet Ly alpha (photons/cm^2/sec) Mercury 3.448e+11 Venus 3.525e+11 Earth 3.523e+11 Mars 3.367e+11 Jupiter 3.367e+11 Saturn 3.525e+11 Uranus 3.563e+11 Neptune 3.629e+11 Pluto 3.613e+11