Obs. : 2016-01-24 Planet Ly alpha (photons/cm^2/sec) Mercury 4.120e+11 Venus 4.040e+11 Earth 3.971e+11 Mars 3.982e+11 Jupiter 3.974e+11 Saturn 3.989e+11 Uranus 4.043e+11 Neptune 4.206e+11 Pluto 4.120e+11