The Aztec Empire ruled over 80,000 square miles of central Mexico for nearly a century—until a small band of Spanish conquistadors brought it down in 1521.

Researchers generally group gut bacteria into six different categories, with varying amounts of these microbes residing in different parts of the digestive tract.

Peek into the love lives of thousands of strangers whom Stanford University researchers have been tracking since 2017 on this interactive page.

Play the role of a student as you try to navigate college and remain debt-free.

Lake Sørvágsvatn sits about 32 meters (105 feet) above sea level, but the taller surrounding cliffs create an optical illusion that makes it appear to float much higher above the ocean.

Fecal transplants can help treat infections by transplanting healthy gut bacteria from a donor into a patient's gastrointestinal tract using samples of human waste, which are turned into a liquid mixture and often delivered via a colonoscopy procedure.

Located on Ross Island in Antarctica, Mount Erebus is the southernmost active volcano on Earth and features a lava lake—one of eight known worldwide as of 2026—that erupts regularly.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks.

Although the moon passes between the sun and Earth each month, its orbit is tilted by five degrees, preventing Earth from experiencing a solar eclipse each month.

Use this tool to calculate the dollar value of your parental mental load, from meal planning to coordinating after-school care, then see resources that help generate solutions.

One of the most famous portraits ever taken is 'Afghan Girl' (1984) by Steve McCurry, yet the subject Sharbat Gula went much of her life without being identified or benefitting from the image's success.

One of the most famous portraits ever taken is "Afghan Girl" by Steve McCurry. Sharbat Gula, the subject of the photo, was not credited until 2002 for her role in the famous National Geographic cover, and continued to live in poverty after the photo was taken.

Watch a breakdown of the canine family tree that explains how foxes and wolves are related to our beloved household pets, like poodles and dachshunds.

Miracle berries make things that normally taste acidic or sour, such as lemons, taste sweet, like sugar-coated candy, by binding a special protein called miraculin to taste buds.

'Golden blood' is the rarest blood type in the world—fewer than 50 people are known to have it.

The US has discontinued a variety of different currency denominations over the years—including a $100K bill.

The average banana produces one positron—the antimatter counterpart to an electron—every 75 minutes as its trace amounts of radioactive potassium decay.

Watch Dr. Laurence Peter explain his 'Peter Principle,' which states that people are promoted to their level of incompetence and explains why bosses aren't always good at their jobs.

Rapid intensification is the increase in a hurricane's sustained wind speed by at least 35 miles per hour within 24 hours, which can strengthen it by up to two categories.

'Tulip mania,' the 1630s Dutch craze where rare bulbs were briefly traded like luxury assets, may have been the first financial bubble—and it still shapes markets today.

Find out how important you are to AI tools when they generate text responses with this tool, which estimates the weights of people's names.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

Give your memories a place to live and explore the personal stories left by strangers, tied to specific locations, in this interactive map of the world.

Emanuel Leutze's painting 'Washington Crossing the Delaware' is one of the defining images of the Revolutionary War.

There are up to 100 trillion microbes in the gut, and maintaining the relative balance in this ecosystem is important for our health.

Explore the 2025 Uber Lost & Found Index to find out the weirdest items that passengers left behind in Ubers last year, from ten live lobsters to a mannequin head with human hair.

Male pattern baldness accounts for more than 95% of hair loss in men and is characterized by thinning hair, hair loss, and a receding hairline.

'Bibliotherapy' is of increasing interest as a way to improve mental health and help navigate complex life situations—with people immersing themselves in the experiences of fictional characters or nonfiction and self-help books to find relief and gain personal insights.

Humans tend to imagine aliens as humanlike, but that's probably unlikely. Three different hypothetical planets show how aliens' bodies could take many forms.

Relax to a livestream of brown bears chilling in Katmai National Park in Alaska.

Examine this captivating animation 'building' a human—illustrating the roughly 40 weeks of fetal development.

Stonehenge was built using giant wooden rollers and precisely carved tongue-and-groove joints to lock the stones in place.

This short animation shows how human beings managed to lug 30-ton stones over miles of prehistoric English countryside and stand them up The Stone Age engineering involved using giant wooden rollers and carving precisely interlocking tongue-and-groove joints to hold the heavy stones in place.

You may be better at spotting a lie when listening to a speaker's voice inflections rather than watching for facial and body cues.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Experience a century of America's healthcare advances with this medical visualization, tracing a sampling of healthcare innovations from head to toe.

Experience 14 billion years of important moments in world history with this scrollable interactive timeline.

Explore how temperatures compare to historical averages in cities worldwide with this interactive global monitor.

Watch a visualization of what it would look like to move along Earth's surface as fast as the International Space Station, or about 23 times the speed of sound.

The animatronic shark from 'Jaws' was a complex machine called 'Bruce.'

Watch what would happen if you literally had all the money in the world.