Earth Day began as a grassroots protest coordinated by a 25-year-old

Earth Day has become the largest civic event in the world

What began in 1970 with 20 million Americans now involves more than 1 billion participants across over 190 countries each year. Earth Day now encompasses rallies, cleanups, and climate actions worldwide.

The massive gathering that rang in the first Earth Day

Earth Day was first celebrated in 1970 and helped inspire a significant nationwide environmental movement. In Philadelphia, the holiday was rung in with a gathering in the city’s Fairmount Park featuring musicians, speakers, and over 10,000 attendees. This video from CBS offers remarkable footage from the day and explains why Philadelphians were especially drawn to the environmental cause.

The environmental crises of the late 1960s led to the founding of the EPA

Disasters such as the Cuyahoga River fire and the Santa Barbara oil spill prompted Congress and President Nixon to establish the Environmental Protection Agency in December 1970, with the goal of unifying federal efforts to control pollution.

Greta Thunberg addressed Davos at 16 years old

In 2019, 16-year-old climate activist Greta Thunberg took the Davos stage to sharply criticize global leaders for failing to act on climate change, warning that incremental promises were meaningless without immediate, systemic action.

How a crew of hippies and nerdy teens in 1970 launched the global phenomenon of Comic-Con

Brinke Stevens and nearly 50 early organizers recount assembling Comic‑Con in 1970s San Diego—starting with just 300 attendees in a hotel basement—and how that grassroots, inclusive mix of fans sparked an enduring and worldwide pop‑culture movement.

David Attenborough received the 2021 Champions of the Earth Lifetime Achievement Award

The UN's highest environmental honor celebrated Attenborough as "one of the leading voices of the global environmental movement." For at least four decades, he collaborated with the UN Environment Programme by advocating for "efforts to counter the climate crisis, biodiversity loss and pollution" and addressing "world leaders at the UN Climate Change Conference" in 2021.

The Kent State massacre sparked a nationwide student strike

In 1970, the Ohio National Guard opened fire on Kent State University students—peacefully protesting the Vietnam War—and killed four. The tragedy led to more widespread nationwide protests, shutting down more than 200 colleges and universities. The event led to a Pulitzer Prize-winning photo of a slain and grieving student.

The Whole Earth Catalog provided an early blueprint for the social internet

The Whole Earth Catalog, a counterculture guide to alternative living, was a repository for hippie ideas. In 1985, its founder decided to bring Whole Earth to the nascent internet with the Whole Earth ‘Lectronic Link, or WELL, an early web forum.

A short-lived dance festival gave a promoter the idea for Coachella

In 1996, Goldenvoice CEO Paul Tollett helped organize the Organic festival, an all-night electronic music festival held at a ski resort east of Los Angeles. Tollett said he was inspired by the way Organic's lineup brought the United Kingdom's burgeoning rave culture to a distinctly picturesque and American venue and environment.

A 21-year-old college student designed the Vietnam Veterans Memorial

In 1981, a 21-year-old Yale architecture student, Maya Lin, won the national design competition for the Vietnam Veterans Memorial. The design was controversial for rejecting heroic statues, using a black wall, and avoiding overt patriotic symbolism.

In 2014, Bill Nye debated young Earth creationist Ken Ham at the Creation Museum

After a video of Bill Nye describing creationism as having a detrimental effect on science education went viral, the cofounder of "Answers in Genesis" posted a response objecting to the claims and invited Nye to debate. More than 11 million people have viewed the event on YouTube.

J.I. Rodale helped pioneer organic farming in the US

Rodale began using the term “organic” in the 1940s to describe farming practices that avoided the use of pesticides and chemicals, which he believed were dangerous. Rodale used a 63-acre farm in Emmaus, Pennsylvania, to cultivate organic food and established a magazine, Organic Farming and Gardening, as well as a foundation based on a simple motto: “Healthy Soil = Healthy Food = Healthy People.”

'Diet for a Small Planet' popularized the vegetarian diet

Frances Moore Lappe’s 1971 book provided recipes for vegetarian dishes, introducing millions to soy, sprouts, and tofu. It also argued that a vegetarian diet was a political act that could solve world hunger by redirecting food from livestock to humans.

The Teacher in Space program was launched in 1984 to highlight spaceflight in US classrooms

Announced by President Ronald Reagan, the program drew more than 11,000 teacher applicants nationwide. Christa McAuliffe was selected to fly on STS-51L, with plans to teach live lessons from orbit before the Challenger disaster ended the mission.

Well before the publication of 'Walden,' Henry David Thoreau nearly burned down his hometown

On April 30, 1844, the transcendentalist set a campfire that quickly grew out of control, burning 300 acres of woods near Concord, Massachusetts. For years, Thoreau remarked that other residents called him the "woods burner." Thoreau, though, felt no guilt, writing in 1850, "It has never troubled me from that day to this more than if the lightning had done it."

Dr. Martin Luther King Jr. used disciplined organizing tactics to win civil rights

This resource focuses on Dr. King as a strategic organizer, detailing how he selected campaign targets, partnered with local leaders, adapted his tactics, developed leadership pipelines, and employed political pressure to convert moral protest into political change.

What did Earth look like when dinosaurs roamed?

The face of the Earth isn’t remotely the same as when the dinosaurs ruled the roost. The passing of millions of years, plate tectonics, and a spotty track record with asteroid collisions have changed the planet’s surface. Use this interactive globe to see what the Earth looked like millions of years ago.

New England towns have practiced direct democracy since the 1700s

Town meetings in New England let residents vote directly on local budgets, laws, and policies. One of the oldest surviving forms of participatory democracy in the United States, the tradition dates back nearly 250 years.

The early success of Facebook made Mark Zuckerberg a college campus celebrity

Within 24 hours of launching in 2004, more than 1,200 Harvard students signed up to the platform, which quickly expanded to other Ivy League and Boston-area schools within months. By year's end, Zuckerberg left Harvard to run the company in California.

Eleanor Roosevelt sheltered student activists at the White House after they were subpoenaed by HUAC

In 1939, when Congress subpoenaed leaders of the American Youth Congress on suspicion of communist ties, Eleanor Roosevelt attended the hearings herself and then invited all 10 students to stay at the White House, as they had nowhere to sleep.

Before writing 'Walden,' transcendentalist Henry David Thoreau nearly burned down his hometown with a campfire that grew out of control.

Prelude to the Tiananmen Square crackdown

On June 2, 1989, two days before the military-led massacre that would come to be known as the Tiananmen Square crackdown, nine of China's top leaders discussed how to stop pro-democracy protesters. During this meeting, leader Deng Xiaoping delivered a speech that has shaped the country ever since, in which he advocated for a forceful end to the protests while supporting China's economic "opening-up" featured in protesters' demands.

The 1974 anarchist protest in Denmark that later inspired SantaCon

An interview with one of the participants explains what the performance art group that planned the event was hoping to achieve. Hordes of Santas walking down the street with a giant goose, attacking buildings with backhoes and pickaxes, handing out “presents” stolen from department stores, and eventually being arrested.

Amateur engineers built America’s first great infrastructure project

With no engineering schools in the US, the Erie Canal was designed and built by self-taught amateurs who improvised new methods and became known as the “Erie School of Engineering.”

Citizen scientist volunteers can help identify invasive species in wilderness areas

Launched in 2005 by the Center for Invasive Species and Ecosystem Health at the University of Georgia, EDDMapS allows users can document invasive species sightings in the US and Canada in a web-based mapping system. As of February 2026, EDDMapS has over 8.6 million records, all freely available for querying.

The origins of Father's Day

Father's Day occurs on the third Sunday in June in the US. It was inspired by the same movement that advocated for Mother's Day, and was first celebrated in 1910. However, the day wasn't official until 1972, many decades after its counterpart, Mother's Day, was formally adopted as a holiday.

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

After NASA's Voyager 1 captured Earth as a single pixel as it left the solar system in 1990, astronomer Carl Sagan used the image to reflect on humanity's fragility and the responsibility to protect 'the only world we've ever known.'

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

A researcher recently discovered an interview from 1967 between groundbreaking journalist Joan Didion and the Grateful Dead, years before the band became an institution.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

70 years ago today, city officials in Santa Cruz, California, banned rock 'n' roll to protect its youth from corruption after witnessing a 'provocative' concert the night before.

The identity of the Tank Man in the iconic photo from the 1989 Tiananmen Square protests remains unknown and was possibly killed.

Jimmy Carter signed a 1978 bill that legalized home brewing, a move credited with kick-starting the craft beer industry.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

Meet the 56 signers of the Declaration of Independence—most of whom didn't put pen to paper until August 2, 1776—and see their original signatures.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

Mid-century modern graphic designers, known for their bright colors and bold lines in advertising, also found success with children's books.

Children are now three times more likely to say they want to be a YouTuber when they grow up than an astronaut, with some even attending 'YouTube camps' that teach kids how to create content for the platform.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Elk Cloner, the first computer virus to spread in public, was written as a practical joke by Richard Skrenta, a Pittsburgh high school student.

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

The US first hosted the World Cup in 1994, a tournament that lives in soccer infamy for its poor planning and the murder of Colombian player Andres Escobar, who'd accidentally scored on his own net.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

Double world record holder Hunter Ewen helped conquer his fear of balloons, called globophobia, by training to win Guinness World Record titles for balloon inflation.

'Silent' fireworks have gained more interest in recent years as a quieter celebratory option.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

Planarian flatworms are small, aquatic worms with exceptional regenerative capabilities. When cut, the worms can regenerate multiple bodies in a matter of weeks.