Obs. : 2023-01-15 Planet Ly alpha (photons/cm^2/sec) Mercury 9.125e+08 Venus 9.561e+08 Earth 9.697e+08 Mars 9.599e+08 Jupiter 9.823e+08 Saturn 9.561e+08 Uranus 9.652e+08 Neptune 9.758e+08 Pluto 9.416e+08