Obs. : 2017-08-31 Planet Ly alpha (photons/cm^2/sec) Mercury 3.695e+11 Venus 3.826e+11 Earth 3.780e+11 Mars 3.695e+11 Jupiter 3.754e+11 Saturn 3.665e+11 Uranus 3.838e+11 Neptune 3.780e+11 Pluto 3.700e+11