Obs. : 2012-03-29 Planet Ly alpha (photons/cm^2/sec) Mercury 4.203e+11 Venus 4.166e+11 Earth 4.235e+11 Mars 4.185e+11 Jupiter 4.171e+11 Saturn 4.252e+11 Uranus 4.194e+11 Neptune 4.214e+11 Pluto 4.254e+11