Obs. : 2011-12-06 Planet Ly alpha (photons/cm^2/sec) Mercury 4.695e+11 Venus 4.781e+11 Earth 5.041e+11 Mars 4.839e+11 Jupiter 4.863e+11 Saturn 4.641e+11 Uranus 4.731e+11 Neptune 4.726e+11 Pluto 4.781e+11