Obs. : 2011-02-08 Planet Ly alpha (photons/cm^2/sec) Mercury 3.627e+11 Venus 3.657e+11 Earth 3.793e+11 Mars 3.627e+11 Jupiter 3.761e+11 Saturn 3.836e+11 Uranus 3.761e+11 Neptune 3.682e+11 Pluto 3.657e+11