Obs. : 2014-08-25 Planet Ly alpha (photons/cm^2/sec) Mercury 4.040e+11 Venus 3.907e+11 Earth 4.220e+11 Mars 4.380e+11 Jupiter 3.907e+11 Saturn 4.312e+11 Uranus 4.079e+11 Neptune 4.133e+11 Pluto 4.278e+11