Obs. : 2018-05-29 Planet Ly alpha (photons/cm^2/sec) Mercury 3.225e+11 Venus 3.250e+11 Earth 3.240e+11 Mars 3.213e+11 Jupiter 3.267e+11 Saturn 3.222e+11 Uranus 3.210e+11 Neptune 3.193e+11 Pluto 3.220e+11