Obs. : 2016-02-01 Planet Ly alpha (photons/cm^2/sec) Mercury 4.050e+11 Venus 3.999e+11 Earth 4.148e+11 Mars 3.985e+11 Jupiter 4.033e+11 Saturn 3.983e+11 Uranus 4.204e+11 Neptune 4.164e+11 Pluto 4.050e+11