Obs. : 2010-10-07 Planet Ly alpha (photons/cm^2/sec) Mercury 3.817e+11 Venus 3.921e+11 Earth 3.657e+11 Mars 3.933e+11 Jupiter 3.657e+11 Saturn 3.817e+11 Uranus 3.657e+11 Neptune 3.735e+11 Pluto 3.926e+11