Obs. : 2013-06-12 Planet Ly alpha (photons/cm^2/sec) Mercury 4.143e+11 Venus 4.143e+11 Earth 4.002e+11 Mars 4.187e+11 Jupiter 4.160e+11 Saturn 4.205e+11 Uranus 4.161e+11 Neptune 3.989e+11 Pluto 3.985e+11