Obs. : 2013-03-14 Planet Ly alpha (photons/cm^2/sec) Mercury 4.508e+11 Venus 4.434e+11 Earth 4.341e+11 Mars 4.322e+11 Jupiter 4.250e+11 Saturn 4.752e+11 Uranus 4.322e+11 Neptune 4.508e+11 Pluto 4.756e+11