Obs. : 2014-12-01 Planet Ly alpha (photons/cm^2/sec) Mercury 4.233e+11 Venus 4.220e+11 Earth 4.009e+11 Mars 4.228e+11 Jupiter 3.898e+11 Saturn 4.233e+11 Uranus 4.184e+11 Neptune 4.192e+11 Pluto 4.243e+11