Everyday is Earth Day, as the saying goes. But, today marks the official celebration.

The first Earth Day – spearheaded by Senator Gaylord Nelson of Wisconsin – was held on April 22,1970.  An estimated 20 million people attended rallies across the US to protest against rampant industrial pollution and the deterioration of the nation’s natural environment. Raising public awareness and shifting the political tide, these events helped put environmental issues on the national agenda. They led to the creation of the EPA and the passage of the Clean Air Act, Clean Water Act, and the Endangered Species Act.

Forty-six years after the original, Earth Day celebrations are now held in nearly 200 countries. This year, the date is more significant than ever as hundreds of government officials from around the world gathered at the UN to sign the Paris Agreement on Climate Change.

“Earth Rise” from 1968 highlighted how fragile and unique the Earth really is.                              Credit: William Anders/NASA