Obs. : 2014-01-29 Planet Ly alpha (photons/cm^2/sec) Mercury 4.029e+11 Venus 3.956e+11 Earth 4.153e+11 Mars 4.039e+11 Jupiter 4.153e+11 Saturn 4.041e+11 Uranus 4.203e+11 Neptune 4.029e+11 Pluto 3.956e+11