Obs. : 2011-05-24 Planet Ly alpha (photons/cm^2/sec) Mercury 4.241e+11 Venus 4.241e+11 Earth 4.064e+11 Mars 4.241e+11 Jupiter 4.206e+11 Saturn 4.209e+11 Uranus 4.118e+11 Neptune 3.847e+11 Pluto 3.993e+11