Obs. : 2016-03-07 Planet Ly alpha (photons/cm^2/sec) Mercury 2.165e+11 Venus 2.172e+11 Earth 2.297e+11 Mars 2.240e+11 Jupiter 2.297e+11 Saturn 2.216e+11 Uranus 2.090e+11 Neptune 2.165e+11 Pluto 2.194e+11