Obs. : 2017-06-02 Planet Ly alpha (photons/cm^2/sec) Mercury 3.345e+11 Venus 3.302e+11 Earth 3.336e+11 Mars 3.375e+11 Jupiter 3.402e+11 Saturn 3.299e+11 Uranus 3.302e+11 Neptune 3.239e+11 Pluto 3.270e+11