What "important" day, started by U.S. Senator Gaylord Nelson (D-Wis), is celebrated in the U.S. on April 22, but by the U.N. on the day of the spring equinox?
Equinox Earth Day Earth Day Network Earthday Earth day Earth Day Earth Week Earth day 2010
earth day network equinox earth day earthday earth day earth week earth day 2010
earth day
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Earth Day