Obs. : 2014-06-08 Planet Ly alpha (photons/cm^2/sec) Mercury 3.750e+11 Venus 3.835e+11 Earth 4.158e+11 Mars 3.836e+11 Jupiter 3.702e+11 Saturn 3.978e+11 Uranus 3.940e+11 Neptune 4.072e+11 Pluto 4.130e+11