Obs. : 2014-02-04 Planet Ly alpha (photons/cm^2/sec) Mercury 3.867e+11 Venus 3.934e+11 Earth 4.193e+11 Mars 4.197e+11 Jupiter 4.123e+11 Saturn 4.054e+11 Uranus 3.837e+11 Neptune 3.867e+11 Pluto 3.934e+11