Obs. : 2015-06-25 Planet Ly alpha (photons/cm^2/sec) Mercury 4.188e+11 Venus 4.488e+11 Earth 3.750e+11 Mars 4.267e+11 Jupiter 4.458e+11 Saturn 3.830e+11 Uranus 4.045e+11 Neptune 3.766e+11 Pluto 3.704e+11