Obs. : 2018-04-25 Planet Ly alpha (photons/cm^2/sec) Mercury 4.450e+11 Venus 4.458e+11 Earth 4.301e+11 Mars 4.301e+11 Jupiter 4.301e+11 Saturn 4.301e+11 Uranus 4.477e+11 Neptune 4.379e+11 Pluto 4.296e+11