Obs. : 2015-04-26 Planet Ly alpha (photons/cm^2/sec) Mercury 5.028e+11 Venus 5.149e+11 Earth 4.890e+11 Mars 4.945e+11 Jupiter 5.268e+11 Saturn 4.890e+11 Uranus 4.894e+11 Neptune 4.835e+11 Pluto 4.799e+11