|When is Earth Day in 2013?|
Earth Day in 2013 is on Monday, April 22.
|What is Earth Day?|
Earth Day is observed on April 22 and was started in the United States in 1970 by Senator Gaylord Nelson to create awareness for the Earth's environment and to encourage conservation efforts. In 1990, Earth Day was taken international, and today, more than 500 million people in 175 countries observe Earth Day.