Obs. : 2013-07-13 Planet Ly alpha (photons/cm^2/sec) Mercury 4.193e+11 Venus 4.164e+11 Earth 4.363e+11 Mars 4.255e+11 Jupiter 4.255e+11 Saturn 4.533e+11 Uranus 4.358e+11 Neptune 4.318e+11 Pluto 4.363e+11