Obs. : 2020-02-01 Planet Ly alpha (photons/cm^2/sec) Mercury 6.022e+08 Venus 6.013e+08 Earth 6.228e+08 Mars 6.266e+08 Jupiter 6.194e+08 Saturn 6.194e+08 Uranus 6.035e+08 Neptune 6.013e+08 Pluto 6.194e+08