Obs. : 2013-03-06 Planet Ly alpha (photons/cm^2/sec) Mercury 3.756e+11 Venus 3.756e+11 Earth 4.270e+11 Mars 3.816e+11 Jupiter 3.911e+11 Saturn 3.985e+11 Uranus 3.791e+11 Neptune 3.756e+11 Pluto 3.711e+11