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Matt Damon Visits A Well Outside Mekele, Ethiopia

MEKELE, ETHIOPIA - APRIL 20: In this handout image provided by PMK/HBH, ONEXONE Foundation Ambassador actor Matt Damon visits a well just outside Mekele, Ethiopia on April 20, 2009. In his right hand he holds a bottle of regular water, in his left is a bottle of dirty water local children in Mekele drink everyday. (Photo by Handout/Getty Images) *** Local Caption *** Matt Damon

Earth Day: Stars and Their Environmental Causes

We're celebrating Earth Day by taking a look at stars who are taking an active role in protecting our planet with their charitable work.