Obs. : 2012-12-14 Planet Ly alpha (photons/cm^2/sec) Mercury 4.072e+11 Venus 4.072e+11 Earth 4.372e+11 Mars 4.081e+11 Jupiter 4.316e+11 Saturn 4.074e+11 Uranus 4.224e+11 Neptune 4.194e+11 Pluto 4.066e+11