When was the first Earth Day? Here's what to know about the holiday

As spring brings the world back into bloom, Earth Day gives us a quiet moment to remember just how special our planet is.

In Arizona, the Earth's wonder is on full display, from the Grand Canyon and Sedona's red rocks to the wildflower meadows of the high country and the sun-washed desert landscapes. It's visible in the unique animals that live here and the spectacular weather each season.

Earth Day is celebrated annually on April 22, showcasing the beauty and diversity of Earth and raising awareness for environmental protection.

Here's what to know about Earth Day and why it's celebrated.

When is Earth Day?

National Geographic states that Earth Day is commemorated annually on April 22 to celebrate the Earth's diverse environment and showcase solidarity for environmental protection.

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What is Earth Day?

According to the official website of the Earth Day Organization, in the years leading up to the first event in 1970, many people were unaware of the environmental impact that fossil fuels and pollution had on human health and the environment.

Following the significant oil spill in Santa Barbara, California in 1969, awareness began to increase and people started to show concern, particularly those who were college students and part of the anti-war movement. It was during this time that Wisconsin Senator Gaylord Nelson, who had long been concerned about the environment, saw an opportunity to harness the passion of students from the anti-war movement and redirect it towards environmental protection.

Nelson proposed the concept of a day dedicated to showing support for the environment on college campuses. With the assistance of young college activist Denis Hayes, who helped spread the idea to a wider audience, they turned the idea into reality. They selected April 22, a weekday situated between final exams and spring break, as Earth Day, aiming to maximize student participation, as reported by the Earth Day Organization.

Recognizing the potential of Earth Day, Hayes assembled a national staff to collaborate with organizations nationwide. The event swiftly gained momentum and attracted national media attention, ultimately being celebrated by 140 countries by 1990.

When was the first Earth Day?

The first Earth Day took place on April 22, 1970.

This article originally appeared on Arizona Republic: When was the first Earth Day? Here's what to know