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Arts & Culture

Kinetic Sculpture and the Illusion of Motion in Alexander Calder's Mobiles

Quick fact

While some of Alexander Calder's sculptures are motorized, his signature mobiles are entirely powered by the air around them—no strings or motors—and no two moments are ever the same.

Why this is interesting

You've seen them: delicate metal shapes dancing in the air, never still. But how do these heavy materials seem to float and drift so effortlessly?