Obs. : 2010-11-25 Planet Ly alpha (photons/cm^2/sec) Mercury 3.882e+11 Venus 3.748e+11 Earth 3.744e+11 Mars 3.882e+11 Jupiter 3.721e+11 Saturn 3.730e+11 Uranus 3.721e+11 Neptune 3.800e+11 Pluto 3.882e+11