Sky Mirror presents a striking means for comparing sky color, as it varies from the nearly white horizon to the deep blue sky directly overhead. A 5' square pole-mounted mirror is angled to reflect the overhead sky. Slowly emerging from the blue field and becoming white, a smaller, viewer-adjustable mirror angles to reflect a transect of sky from overhead to the horizon. The effect is akin to an animated Josef Albers painting made up from sky color alone. A control and information pedestal is placed along an existing path 80 feet away.