Obs. : 2011-08-06 Planet Ly alpha (photons/cm^2/sec) Mercury 3.951e+11 Venus 3.959e+11 Earth 3.908e+11 Mars 4.034e+11 Jupiter 4.056e+11 Saturn 4.018e+11 Uranus 4.016e+11 Neptune 3.949e+11 Pluto 3.927e+11