condition mean min max 4 h after light 571.5 571.5 571.5 8 h after light 563.05 503.1 623.0 12 h after light 857.55 632.4 1082.7 4 h after dark 815.45 586.5 1044.4 8 h after dark 548.25 456.3 640.2 12 h after dark 504.5 489.2 519.8