Obs. : 2016-03-04 Planet Ly alpha (photons/cm^2/sec) Mercury 2.168e+11 Venus 2.168e+11 Earth 2.312e+11 Mars 2.221e+11 Jupiter 2.312e+11 Saturn 2.191e+11 Uranus 2.008e+11 Neptune 2.160e+11 Pluto 2.179e+11