Obs. : 2016-05-21 Planet Ly alpha (photons/cm^2/sec) Mercury 4.252e+11 Venus 4.251e+11 Earth 4.196e+11 Mars 4.196e+11 Jupiter 4.115e+11 Saturn 4.196e+11 Uranus 4.218e+11 Neptune 4.175e+11 Pluto 4.224e+11