Obs. : 2015-12-14 Planet Ly alpha (photons/cm^2/sec) Mercury 4.390e+11 Venus 3.900e+11 Earth 4.519e+11 Mars 3.970e+11 Jupiter 4.207e+11 Saturn 4.082e+11 Uranus 4.425e+11 Neptune 4.528e+11 Pluto 4.390e+11