Obs. : 2014-03-31 Planet Ly alpha (photons/cm^2/sec) Mercury 3.963e+11 Venus 3.955e+11 Earth 4.015e+11 Mars 4.015e+11 Jupiter 4.162e+11 Saturn 4.056e+11 Uranus 4.019e+11 Neptune 3.944e+11 Pluto 3.998e+11