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20 Earth Day Facts You Should Know

Updated: May 04, 2024

We hope these Earth Day facts help raise environmental awareness—and the importance of taking action now

Inflatable globe on a meadow against sky
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Brush up on these Earth Day facts for April 22

Earth is a planet with an abundance of natural beauty. The luscious green forests, the breathtaking waterfalls, the rugged-yet-serene mountains—there’s so much to admire and explore on our planet. Luckily, we have a day where we not only appreciate this natural beauty, but also spotlight ways to conserve it for future generations: Earth Day. And there are plenty of interesting Earth Day facts to learn! But, first, a little background.

Why is Earth Day so important?

Earth Day falls on April 22 each year (a Monday in 2024) and is a day to raise awareness about the environmental issues our planet faces. Some people attend environmental conservation and awareness events on Earth Day, while others organize cleanups, plant trees or lead recycling efforts. Even sharing Earth Day quotes on social media raises awareness for its mission. Want to learn more about Earth Day? Read up on these Earth Day facts below.

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people gather in a park in New York City with banners to celebrate the first Earth Day, April 20, 1970
Santi Visalli/Getty Images

Earth Day started in the 1970s

Here’s an Earth Day fact everyone should know: Earth Day was first observed on April 22, 1970, followed in 1972 by World Environment Day. It has been celebrated ever since, slowly but surely picking up steam over the past 50+ years as more and more people have recognized the importance of taking care of our planet.

View of cherry blossoms with the UN General Assembly building in the background in New York City.
Pacific Press/Getty Images

Earth Day is also called International Mother Earth Day

In 2009, the General Assembly of the United Nations labeled April 22 International Mother Earth Day. But, don’t worry if you didn’t know this Earth Day fact, because the United States has yet to adopt the name.

Indian schoolchildren take part in a parade to mark Earth Day in New Delhi, 22 April 2007.

Earth Day is now a global event

Interesting Earth Day fact: It remained a grassroots affair for 20 years, before going global and spreading out to 140 countries in 1990. Earth Day is now celebrated in more than 190 countries, with an estimated 1 billion people the world over participating each year.

Portrait of American politician US Senator Gaylord Nelson (1916 - 2005), founder of Earth Day, as he poses in Rock Creek Park, Washington DC, January 1990.
Janet Fries/Getty Images

Earth Day was the brainchild of Wisconsin Governor Gaylord Nelson

Gaylord Nelson, a two-term governor of Wisconsin (1958 to 1962), was responsible for focusing his state’s environmental policy, establishing a single Department of Resource Development, a Youth Conservation Corps and setting aside $50 million to buy land and convert it to parks and wilderness areas during the years he was in office. This earned him the nickname “Conservation Governor.”

Nelson was then elected a U.S. senator, where he became known as a champion for the earth, asserting that “Environment is all of America and its problems. It is rats in the ghetto. It is a hungry child in a land of affluence. It is housing not worthy of the name; neighborhoods not fit to inhabit.”

Preparations for Earth Day Teach - In Start; Readying a display booth at Currigan Hall are, from left. Charles Petersen, project officer, and Ed Harris and Bob Page, recreation resource specialists with the U.S. Department of the Interior Bureau of Outdoor Recreation; April 1970.
Millard Smith/Getty Images

Earth Day started as a teach-in for the environment

Frustrated by a lack of support for environmental policy among his fellow senators, but inspired by the various youth movements of the ’60s that were pushing hard for meaningful societal change, Nelson devised the idea of a teach-in for the environment in 1969. The plan was to drum up public support for the nascent environmental movement, with an eye toward engendering the political will to make change. As a fun Earth Day fact: Nelson’s idea was so popular that he hired an 85-person team to get the first Earth Day off the ground.

An Earth Flag hangs from the stoop of a home on Sherman Avenue in the Parkside Neighborhood in Portland, ME
Portland Press Herald/Getty Images

Earth Day has a flag

The Earth Day flag, also known as Earth Flag, was designed by John McConnell in 1970. The flag features a photographic image of Earth that was taken during the flight of Apollo 10 in 1969. The image is depicted on a dark blue background and showcases a view of Earth as seen above the Indian Ocean. The flag was updated in 1973 to feature The Blue Marble, a photo of Earth taken by the Apollo 17 crew during their trip to the moon on December 7, 1972.

the skyline of downtown Los Angeles including the city hall (center) and the United States Courthouse (left), and Hall of Justice (right) shrouded and obscured by smog, a form of industrial and automotive air pollution particularly problematic in the area during the mid 20th Century, 1956.
American Stock Archive/Getty Images

Earth Day was needed even back in the 1950s and 1960s

We may think of man-made climate change as a recent development, but it’s one of the most critical Earth Day facts: Even decades ago, the country was a polluted place in need of help. Public lands were dilapidated, factories were free to dump toxins into our waters and industries could churn out pollutants into our air without regulation. As a result, species began collapsing—oysters, for example, were gone from New York Harbor by the early 20th century. Around the time of the first Earth Day in 1970, people were starting to realize that pollution and toxic waste could lead to cancer and other serious health issues.

Planet Earth In Headphones on starry sky background
Maciej Toporowicz, NYC/Getty Images

Earth Day has a theme song

“Earth Anthem” was written by Indian poet and diplomat Abhay Kumar in 2008. Kumar’s lyrics were inspired by the Blue Marble image of Earth, along with the Indian philosophy of “Vasudhaiva Kutumbakam,” which translates to “The World Is One Family.” The song has also been translated into over 150 world languages to celebrate Earth Day.

Thousands of young people stretched out over a mile walking along a closed river drive during a Philadelphia Earth Walk, April 22, 1970.
Bettmann/Getty Images

Earth Day was celebrated by 10% of the U.S. population 

Nelson chose this date in the third week of April to appeal to his core demographic—students—and April 22 fell between their spring break and final exams. Enormous  inspirational rallies were held all over the country, with 20 million people—10% of the U.S. population at that time—taking to the streets.

Biologist And Author Rachel Carson
Bettmann/Getty Images

Earth Day was inspired by a book

Rachel Carson was a marine scientist for the U.S. Fish and Wildlife Service and was inspired to write Silent Spring in 1962. The nonfiction book was a wake-up call that shined a spotlight on the dangers of pesticides and environmental threats. With the book’s release (and more than half a million copies sold), Carson sparked an environmental movement and raised awareness of the issues our earth faces.

A flag with the EPA logo flies in front of the Environmental Protection Agency on Tuesday, Jan. 1, 2019.
Bill Clark/Getty Images

Earth Day’s origin spurred immediate action

The impact of that first Earth Day was immediate and profound; by December of 1970, President Richard Nixon had established the Environmental Protection Agency and the Clean Air Act was devised and passed that year. Swiftly on their heels came the Clean Water Act, the Endangered Species Act, the Resource Conservation and Recovery Act, the Federal Environmental Pesticide Control Act and the Federal Land Policy and Management Act, among other critical pieces of legislation.

Afghan laborers preparing the ground on earth day

Earth Day sparked a tree-planting campaign in 2011

On Earth Day in 2011, a remarkable campaign called “Plant Trees Not Bombs,” saw 28 million trees take root in Afghanistan. The campaign was and continues to be a powerful reminder that even in the face of conflict, we can nurture hope and growth for a greener future.

A close-up of a hand holding up an Earth day button which reads, 'Save your Earth - You can't get off.'
Harold M. Lambert/Getty Images

Earth Day changed public opinion

The first Earth Day also changed public opinion on environmental protection. History.com reports that according to the EPA, 25% of the United States public said environmental protection was an important goal when polled in May 1971. That was a whopping 2,500% increase compared to 1969.

Circle of people at Earth Day Ceremony
Joe Sohm/Visions of America/Getty Images

Earth Day went global in 1990

On the occasion of its 20th birthday in 1990, Earth Day’s organizers decided the time had come to take the movement global— 200 million people in 141 countries participated. The impacts of that day were enormous: It kicked off massive initiatives to recycle and paved the way for the 1992 United Nations Earth Summit in Rio de Janeiro.

The United Nations logo on the back wall of the General Assembly Hall of the United Nations is seen from the floor May 12, 2006 at the United Nations headquarters in New York.
Chris Hondros/Getty Images

Earth Day celebrations were joined by The United Nations in 2000

By the time of Earth Day’s 30th anniversary, coinciding with a brand new millennium, Earth Day was being announced by the United Nations.

“At the end of the 20th and the dawn of the 21st century, the human species had entered a new era where the nature of the entire planet was being fundamentally changed,” the international organization said in a statement about the day. “Humankind was facing epidemics, massive holes in the ozone layer and the change in global climate. In that context, it was necessary to have an informed citizenry, which would take a leadership role in pulling the political and economic forces in the right direction. It was time for a formidable shift, both at high and low levels. In the year 2000, a decision had been made to focus on energy and climate change.”

digital model of the earth

Earth Day went virtual in the 21st century 

The year 2000 also marked the era when the Internet helped spread the message of the need for strong environmental policy far and wide. Being virtually connected allowed 5,000 environmental groups to find each other and coordinate their messaging. It allowed people from 184 countries to join in marches and demonstrations and acts of organizing.

group of people's hands holding plants growing out of soil; planting trees for Earth Day concept
PeopleImages/Getty Images

Earth Day celebrations have a yearly theme

That’s right—Earth Day has a theme each year—this year’s is  “Planet vs. Plastics.” According to earthday.org, the theme calls for everyone “to advocate for widespread awareness on the health risk of plastics, rapidly phase out all single-use plastics, urgently push for a strong UN Treaty on Plastic Pollution and demand an end to fast fashion.”

Marchers head down Constitution Avenue toward the U.S. Capital Building during the Earth Day March for Science on April 22, 2017 in Washington, DC.
Paul Morigi/Getty Images

Earth Day is supported by scientists

Let’s not forget one of the important Earth Day facts: Although the March for Science began as its own separate movement in February 2017, by April of that year, it joined Earth Day marches and celebrations in Washington, D.C. and 360 other cities. While the group’s aims of protecting science from “manipulation by special interests” and opposing policies that “threaten to further restrict scientists’ ability to research and communicate their findings” are not solely related to the health of the Earth, they do go hand-in-hand with supporting environmentalists and earth scientists.

Pakistani representatives of non governmental orgainzations gather during the Earth Day ceremony in Karachi, 22 April 2007.

Earth Day is still a grassroots movement

While yes, Earth Day has become a global phenomenon, it still counts on local initiatives to demonstrate the power of change on a smaller but still-critical level. A few examples: In 2015, Tanzania led efforts to protect the Usambara Mountains, including teaching residents about how to conserve water; in Puerto Rico, celebrations centered around the establishment of a new eco-park and an initiative was put in place to keep the island trash free for 100 days.

First crocuses in snow. Purple spring flowers
Olga U/Getty Images

Earth Day is different from Equinox Day

It may be easy to confuse Earth Day with Equinox Day, but keep this Earth Day fact in mind when April 22 comes along. Although Equinox Day also involves celebrating the harvest and caring for our planet, it’s held on the first day of spring; 2024’s spring equinox was on March 19.

Street painters depict colorful scenes of nature in Manila's Makati financial district on May 4, 2008 in a special city-wide "Earth Day" celebration.
JAY DIRECTO/Getty Images

Earth Day continues the discussion for positive change 

As Earth Day’s founding organization reports, all this interest and action has not been without its counterpoint from climate change deniers, lobbyists, politicians and more. Despite the challenges, it’s an Earth Day fact that the day is considered “the largest secular observance in the world.” That is no small feat, and although corporate interests continue to plague meaningful efforts at policy change to make the world more livable, the fact that, by 2010, Earth Day had coordinated with 75,000 global partners—and that number has only grown since then—is cause for celebration.

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  • Earthday.org: “Earthday.org Announces Theme For Earth Day 2023: “Invest In Our Planet”’
  • American Flags: “Everything to Know About Earth Flag and Earth Day Flag”
  • ACS Chemistry for Life: “Legacy of Rachel Carson’s Silent Spring”
  • Business Standard: “Artists across world celebrate Earth Day with Indian poet’s ‘Earth Anthem'”