condition mean min max 4 h after light 6.85712 6.77887 6.93537 8 h after light 11.8284 11.6051 12.0517 12 h after light 19.3403 16.8641 21.8165 4 h after dark 11.64723 9.89596 13.3985 8 h after dark 14.00485 13.8272 14.1825 12 h after dark 10.63155 10.6082 10.6549