condition mean min max 4 h after light 8.870442 8.458557 9.282327 8 h after light 9.378823 9.107577 9.650069 12 h after light 9.3950695 9.107577 9.682562 4 h after dark 9.3428685 9.107577 9.57816 8 h after dark 9.1090175 9.034866 9.183169 12 h after dark 8.782575 8.782575 8.782575