Obs. : 2013-11-10 Planet Ly alpha (photons/cm^2/sec) Mercury 4.227e+11 Venus 3.993e+11 Earth 4.101e+11 Mars 4.475e+11 Jupiter 4.308e+11 Saturn 4.127e+11 Uranus 4.092e+11 Neptune 4.150e+11 Pluto 3.993e+11