Obs. : 2010-05-24 Planet Ly alpha (photons/cm^2/sec) Mercury 3.720e+11 Venus 3.711e+11 Earth 3.743e+11 Mars 3.811e+11 Jupiter 3.670e+11 Saturn 3.804e+11 Uranus 3.670e+11 Neptune 3.666e+11 Pluto 3.743e+11