London, UK | An installation at London's Tate Modern in 2003, in the gallery's famous Turbine Hall.
Danish artist Olafur Eliasson used a semicircular disc, which reflected in the mirrored ceiling to appear circular, made up of hundreds of monochromatic lamps radiating yellow light.
Humidifiers created a fine mist in the air, and visitors could see themselves in the huge ceiling mirror as tiny black shadows.
Displayed for six months, the work attracted two million visitors.
PICTURE OF THE DAY