Obs. : 2012-11-26 Planet Ly alpha (photons/cm^2/sec) Mercury 4.002e+11 Venus 4.002e+11 Earth 3.837e+11 Mars 3.862e+11 Jupiter 3.827e+11 Saturn 4.002e+11 Uranus 3.536e+11 Neptune 3.561e+11 Pluto 3.862e+11