Obs. : 2009-11-26 Planet Ly alpha (photons/cm^2/sec) Mercury 3.567e+11 Venus 3.574e+11 Earth 3.540e+11 Mars 3.577e+11 Jupiter 3.520e+11 Saturn 3.564e+11 Uranus 3.492e+11 Neptune 3.520e+11 Pluto 3.561e+11