Obs. : 2011-08-26 Planet Ly alpha (photons/cm^2/sec) Mercury 3.961e+11 Venus 4.007e+11 Earth 4.211e+11 Mars 4.076e+11 Jupiter 4.156e+11 Saturn 4.042e+11 Uranus 4.190e+11 Neptune 4.190e+11 Pluto 4.212e+11