April 22, 1970: Rallies across the United States mark the first "Earth Day," organized by student Denis Hayes and U.S. Senator Gaylord Nelson.
April 22, 1984: Ansel Adams, photographer of iconic nature scenes in the American West, dies in Carmel, California.
April 22, 1994: Richard M. Nixon, dies on Earth Day. The President who once said that environmentalists wanted to "live like a bunch of damn animals," had an impressive string of environmental achievements. Nixon signed laws that created the Environmental Protection Agency, limited pesticide use and required environmental impact statements for development projects. He also signed the Clean Air Act, the Clean Water Act, and the Endangered Species Act.
April 22, 2010: On the fortieth anniversary of the first Earth Day, the Deepwater Horizon drilling platform sinks in the Gulf of Mexico two days after an explosion and fire. The resulting oil spill becomes the biggest in U.S. history.
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