Obs. : 2010-12-03 Planet Ly alpha (photons/cm^2/sec) Mercury 3.794e+11 Venus 3.712e+11 Earth 3.716e+11 Mars 3.794e+11 Jupiter 3.771e+11 Saturn 3.684e+11 Uranus 3.778e+11 Neptune 3.789e+11 Pluto 3.794e+11