Obs. : 2014-12-30 Planet Ly alpha (photons/cm^2/sec) Mercury 4.590e+11 Venus 4.551e+11 Earth 4.130e+11 Mars 4.486e+11 Jupiter 4.005e+11 Saturn 4.184e+11 Uranus 4.160e+11 Neptune 4.400e+11 Pluto 4.590e+11