Obs. : 2013-06-18 Planet Ly alpha (photons/cm^2/sec) Mercury 4.262e+11 Venus 4.262e+11 Earth 4.415e+11 Mars 4.306e+11 Jupiter 4.247e+11 Saturn 4.608e+11 Uranus 4.299e+11 Neptune 4.245e+11 Pluto 4.415e+11