Obs. : 2018-02-28 Planet Ly alpha (photons/cm^2/sec) Mercury 3.515e+11 Venus 3.515e+11 Earth 3.492e+11 Mars 3.491e+11 Jupiter 3.509e+11 Saturn 3.493e+11 Uranus 3.474e+11 Neptune 3.515e+11 Pluto 3.494e+11