Obs. : 2013-02-10 Planet Ly alpha (photons/cm^2/sec) Mercury 4.138e+11 Venus 4.182e+11 Earth 4.291e+11 Mars 4.167e+11 Jupiter 4.115e+11 Saturn 4.362e+11 Uranus 4.151e+11 Neptune 4.167e+11 Pluto 4.173e+11