Obs. : 2013-03-28 Planet Ly alpha (photons/cm^2/sec) Mercury 4.257e+11 Venus 4.682e+11 Earth 4.159e+11 Mars 4.682e+11 Jupiter 4.562e+11 Saturn 3.988e+11 Uranus 4.464e+11 Neptune 4.140e+11 Pluto 3.864e+11