Obs. : 2017-07-26 Planet Ly alpha (photons/cm^2/sec) Mercury 3.746e+11 Venus 3.597e+11 Earth 3.612e+11 Mars 3.665e+11 Jupiter 3.738e+11 Saturn 3.610e+11 Uranus 3.532e+11 Neptune 3.545e+11 Pluto 3.612e+11