Obs. : 2014-12-29 Planet Ly alpha (photons/cm^2/sec) Mercury 4.312e+11 Venus 4.243e+11 Earth 3.920e+11 Mars 4.160e+11 Jupiter 3.828e+11 Saturn 4.037e+11 Uranus 3.898e+11 Neptune 4.041e+11 Pluto 4.312e+11