Obs. : 2015-09-11 Planet Ly alpha (photons/cm^2/sec) Mercury 4.496e+11 Venus 4.564e+11 Earth 4.142e+11 Mars 4.572e+11 Jupiter 4.546e+11 Saturn 4.405e+11 Uranus 4.176e+11 Neptune 4.242e+11 Pluto 4.343e+11