Obs. : 2014-01-07 Planet Ly alpha (photons/cm^2/sec) Mercury 3.933e+11 Venus 3.933e+11 Earth 4.490e+11 Mars 4.051e+11 Jupiter 4.490e+11 Saturn 3.826e+11 Uranus 4.224e+11 Neptune 4.013e+11 Pluto 3.775e+11