Obs. : 2014-09-15 Planet Ly alpha (photons/cm^2/sec) Mercury 4.189e+11 Venus 4.147e+11 Earth 3.997e+11 Mars 4.152e+11 Jupiter 4.139e+11 Saturn 4.168e+11 Uranus 4.049e+11 Neptune 3.955e+11 Pluto 4.056e+11