Obs. : 2018-09-11 Planet Ly alpha (photons/cm^2/sec) Mercury 4.135e+11 Venus 4.240e+11 Earth 4.278e+11 Mars 4.268e+11 Jupiter 4.235e+11 Saturn 4.247e+11 Uranus 4.296e+11 Neptune 4.249e+11 Pluto 4.259e+11