Obs. : 2016-04-28 Planet Ly alpha (photons/cm^2/sec) Mercury 4.111e+11 Venus 4.159e+11 Earth 4.260e+11 Mars 4.260e+11 Jupiter 4.062e+11 Saturn 4.294e+11 Uranus 4.159e+11 Neptune 4.165e+11 Pluto 4.299e+11