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Earth Hour 2010

Palace of Culture and Science in Warsaw, Poland

Photo: ZUMA Press

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60 minutes for the planet

First organized by the World Wildlife Fund in 2007, Earth Hour is an awareness event that asks individuals and businesses to turn off all non-essential lighting between 8:30 and 9:30 p.m. on the last Saturday of March. Since its inception, it has gained global recognization with 126 countries participating.

A composite picture shows the Palace of Culture and Science in Warsaw, Poland, before and after turning off lights for the third annual Earth hour on March 27.