Obs. : 2010-06-24 Planet Ly alpha (photons/cm^2/sec) Mercury 3.681e+11 Venus 3.749e+11 Earth 3.783e+11 Mars 3.900e+11 Jupiter 3.702e+11 Saturn 3.941e+11 Uranus 3.702e+11 Neptune 3.729e+11 Pluto 3.848e+11