Obs. : 2026-07-11 Planet Ly alpha (photons/cm^2/sec) Mercury 8.288e+08 Venus 7.984e+08 Earth 7.244e+08 Mars 8.478e+08 Jupiter 8.288e+08 Saturn 7.852e+08 Uranus 8.356e+08 Neptune 7.794e+08 Pluto 7.244e+08