Obs. : 2013-03-11 Planet Ly alpha (photons/cm^2/sec) Mercury 4.152e+11 Venus 4.152e+11 Earth 4.487e+11 Mars 4.103e+11 Jupiter 4.076e+11 Saturn 4.607e+11 Uranus 4.082e+11 Neptune 4.175e+11 Pluto 4.388e+11