Obs. : 2013-09-10 Planet Ly alpha (photons/cm^2/sec) Mercury 3.703e+11 Venus 3.620e+11 Earth 3.849e+11 Mars 3.741e+11 Jupiter 3.717e+11 Saturn 3.665e+11 Uranus 3.729e+11 Neptune 3.849e+11 Pluto 3.850e+11