Obs. : 2017-02-28 Planet Ly alpha (photons/cm^2/sec) Mercury 3.676e+11 Venus 3.651e+11 Earth 3.691e+11 Mars 3.651e+11 Jupiter 3.706e+11 Saturn 3.633e+11 Uranus 3.651e+11 Neptune 3.650e+11 Pluto 3.638e+11