The average eruption cycle of the Yellowstone supervolcano is 735,000 years

Many believe a cataclysmic volcanic eruption is imminent at Yellowstone, though experts say it is unlikely

Mike Poland, a scientist at the Yellowstone Volcano Observatory, estimates the likelihood of the event at one in a million. He cautions, though, that the park poses other potential dangers, including steam explosions and earthquakes.

Volcanoes can be active, dormant, or extinct based on the recency of eruptions

Active volcanoes may be in the process of erupting or expected to erupt in the future, having done so within the past 11,650 years. Dormant volcanoes have no short-term eruption history, but are expected to erupt in the future, while extinct volcanoes lack the history and expectation.

Human activities release 100 times the carbon dioxide of all volcanic eruptions

While gases released by volcanoes contribute to climate change, humans produce the carbon dioxide equivalent of a Mount St. Helens-sized eruption every 2.5 hours, or more than one Yellowstone eruption yearly, even though such supervolcanoes only erupt about every 100,000 to 200,000 years or more.

Yellowstone National Park is situated atop an active supervolcano

Yellowstone showcases geothermal phenomena, including the famous Old Faithful geyser and the vibrant Grand Prismatic Spring. The park's unique geological and ecological features make it an exceptional destination for visitors from around the globe.

Supervolcanoes can eject enough material to fill one-fourth of the Grand Canyon

Although extremely rare, their released material can trigger winters by blocking the sun and cooling the Earth’s surface for years. The Toba supereruption 74,000 years ago disrupted food chains and reduced the human population to a few thousand.

Vesuvius has erupted nearly 40 times since Pompeii

With a 17,000-year history and dozens of eruptions since 79 CE, Vesuvius sits atop volatile geological forces that make it an unusually explosive volcano. This explainer breaks down why the volcano remains dangerous today.

Eruption forecasting relies on probabilistic methods resembling weather forecasting

While some volcanoes erupt with predictable signs, such as surface deformation from the build-up of underground magma pressure, others release magma at inconsistent rates. Extensive monitoring is needed to identify less clear patterns and indicators of future eruptions.

Volcanoes 'die' when their supply of magma runs out, if they are shifted away from their underlying magma reservoir, or if they get clogged by collapsing or their magma cooling back into rock.

The deadliest aspect of volcanic eruptions is often not lava, but pyroclastic flows—avalanches of ash, gas, and rock that can move more than half the speed of sound.

The deadliest aspect of volcanic eruptions is often not lava, but pyroclastic flows—avalanches of ash, gas, and rock that can move more than half the speed of sound.

Cerulean eruptions result from sulfur being heated by molten rock

During eruptions, warm-colored lava at temperatures between 700 and 1,200 degrees Celsius (1,300 and 2,200 degrees Fahrenheit) burns minerals as they escape from underground reservoirs. In some volcanoes, such as Indonesia's Kawah Ijen and Ethiopia's Danakil Depression, abundant sulfur compounds that burn with blue flames appear to change the color of the melted rock.

Visualize the power and frequency of earthquake magnitudes

About 150 medium earthquakes—magnitude 6.0—occur every year, resulting in moderate shaking and some property damage. While millions of earthquakes below category 2.0 occur yearly, fewer than one of category 9.0 or higher occurs on average.

Scientists monitor volcanoes with a suitcase-sized observatory called SKATE

Short for Setup for the Kinematic Acquisition of Explosive Eruptions, the device is left to record heat, sound and visual data while volcanologists remain at a safe distance. The $58,000 tool is the successor to the FAMoUS (Fast Multiparametric Setup) prototype.

Since 1600, the longest stretch without an outbreak that killed 10,000 was four years

We think of pandemics as unlikely events, but disease outbreaks are surprisingly common. Over the past 400 years, the longest stretch without an outbreak that killed at least 10,000 people was just four years. The next pandemic can't be precisely known, so experts and policymakers focus on preparation.

Learn why water can take millions of years to be recycled via the hydrologic cycle

While a single drop of water spends an average of nine days in the atmosphere before precipitating back to Earth, it can spend thousands of years in the ocean before evaporating, and hundreds of thousands of years deep in rock layers before being released as steam in volcanic eruptions. Some water molecules have been trapped in Antarctic ice sheets for millions of years since they last moved through the water cycle.

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

The world's longest-burning fire

This coal fire in New South Wales, Australia, a common occurrence at coal mines, has been burning for at least 5,500 years, and shows no signs of stopping.

Mapping how human population has grown throughout history

It took 200,000 years for our human population to reach 1 billion—and only 200 years to reach 7 billion. When will our global population peak? And how can we minimize our impact on Earth’s resources, even as we approach 11 billion?

The intensity of auroral activity approximately follows the sun's 11-year cycle

The density, speed, and temperature of material ejected by the sun are at their lowest at the start of each cycle, resulting in weaker interactions with Earth's magnetic field and muted, diffuse auroras. While the average solar wind speed is about 300 kilometers (186 miles) per second, the fastest winds can be more than three times faster.

Earth's core is about 2.5 years younger than its surface according to relativity

Due to differences in where objects are located within gravitational fields, time will run at different rates, which has major impacts on technology that relies on synchronization. For example, GPS satellites run about 38 microseconds faster every day than clocks on Earth's surface, resulting in GPS discrepancies of about six miles, were it not for software corrections.

People spent more than a billion hours visiting national park sites in 2025

Overall, the National Park Service reported 323 million visits for the calendar year, with 26 parks reporting record years. Here's how that broke down by type of site:

Intended to last four years, the Voyager spacecraft have lasted nearly five decades

Launched in 1977, the Voyager probes still send data from billions of miles away, guided by engineers who’ve turned down promotions to stay with the mission. The team continues to support the probes as they move 37,000 mph through space.

Compare various El Niño-Southern Oscillations using maps of atmospheric and ocean variables

Because the intensity of the phases in the cycle is sensitive to small variations in atmospheric and ocean conditions and depends on complex interactions between these two systems, no two El Niño or La Niña events are identical. This contributes to the variability in the length of each phase, which is why an ENSO can last as little as two years or as long as seven.

Estimates say 2.5 billion total T. rexes lived on Earth

Roughly 68 million years ago, the Tyrannosaurus rex was king of the North American ecosystem. Researchers used the dinosaur's size, metabolic rate, age of sexual maturity, and other factors to determine 20,000 individuals likely were alive at any given time, more than 120,000 20-year generations. This piece breaks down how they arrived at those numbers.

Over a lifetime, the average American's nuclear power usage creates a hockey puck of nuclear waste

Spent nuclear fuel remains hot and highly radioactive for long periods, requiring submersion in cooling pools before being stored in dry casks and deep underground repositories. The potential recycling of nuclear waste is impeded by security concerns and dangerous reprocessing methods, particularly when obtaining fresh uranium is often easier.

Flood recurrence intervals are based on independent probabilities

The term "100-year flood" does not mean the event will only occur once every 100 years, but it has a 1% chance of occurring in any given year. Soil saturation, watershed size, and urban development can impact flood severity.

Niagara Falls is slowly eroding backward toward Lake Erie

At its current erosion rate of roughly one foot per year, Niagara Falls is expected to retreat all the way to Lake Erie in about 50,000 years.

Unique species evolved independently on each Galápagos island

The islands formed over millions of years because of a hot spot in the Nazca Plate, where magma breaks through and forms volcanoes. As these islands drifted, plants and animals became secluded, making each island its own an isolated experiment that would influence Charles Darwin's theory of evolution.

Track the location of the Voyager probes, currently between 13 and 15 billion miles away from Earth.

Explore the archaeological treasures of Pompeii, the city buried under volcanic ash when Mount Vesuvius erupted in 79 CE.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

Fireworks-related ER visits are on the rise—in 2024, they increased by 52% as compared to the prior year.

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.

Three Ebola species are responsible for most large outbreaks of the disease, yet the only approved Ebola vaccine is known to work against just one of them.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

Neutron stars, the remains of some massive stars after they explode in a supernova, are the densest directly observable objects in the universe.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Urushiol, the oily toxin in poison ivy, can remain allergenic on clothing for years.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Coral polyps reproduce via broadcast spawning, where entire reefs simultaneously release reproductive cells for about one hour, once a year.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

A century of Billboard issues documenting the evolution of popular music.

44% of Americans say they pray at least once a day—discover how your state's religiosity stacks up against the rest of the country.

The Russia-Ukraine conflict is the largest ground war in Europe since World War II in casualties, forces mobilized, and displacement of civilians.

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

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.

Domino's Pizza's 30-minute delivery guarantee was responsible for the chain's 1980s surge, but it was discontinued after the company was found liable for delivery driver accidents.