Why Captain America sparked outrage in 1940

The collapse of gas bubbles in the joint synovial fluid causes 'cracking' knuckles.

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.

If the moon were less than one-twelfth its current distance from Earth, the planet's tidal forces would overcome the moon's internal gravity, tearing it apart and forming a ring of debris.

George Lucas used Joseph Campbell's 'hero's journey,' a narrative structure that encompasses the common characteristics of multiple cultures' mythologies, to revise 'Star Wars.'

Robert Smalls escaped slavery by piloting a stolen Confederate ship to freedom, then became an influential Black political leader during Reconstruction.

Explore a detailed map of Odysseus' fictional journey from 'The Odyssey.'

Author David Foster Wallace's 'This Is Water' speech provides guidance for adulthood.

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

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

The US jobs projected to shrink the fastest over the next decade include typists and word processors.

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.

Listen to audio clips from Hoover, a harbor seal named after its insatiable appetite, who learned to say English phrases such as 'hello there' and 'come over here.'

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.

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

A dog's nose can be up to 100,000 times more sensitive than a human's, and each possesses a secondary organ for smelling, which helps learn about other dogs when they sniff each other's butts.

Explore an interactive timeline of Earth's 4.5-billion-year history to visualize shifting landmasses and oceans, view the locations of significant asteroid impacts, and learn about major geological and biological events.

Explore 3D models of some of the most dangerous viruses, allowing us to understand these and other pathogens in new ways.

Lesser-known phobias include turophobia, or the fear of cheese, and nomophobia, the fear of being without your cell phone.

Streaming service Netflix's sound logo 'Tudum' was designed as a key sonic differentiator.

Watch President John F. Kennedy's speech on going to the moon

Simulations suggest that a paper airplane launched from the International Space Station would maintain its orientation and gradually descend for 3.5 days before chaotically tumbling down and burning up.

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

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

The tallest tsunami in recorded history was 524 meters (1,720 feet) high—taller than the Empire State Building—and occurred in Lituya Bay, Alaska, in 1958 after an earthquake dislodged a rockface into the water.

The Berlin Wall physically separated East and West Berlin for nearly three decades, preventing East Germans from fleeing to the West and earning the nickname 'the Iron Curtain.'

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.

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

Watch a two-year time-lapse of a pinecone seed transforming into a pine tree.

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

Explore an interactive forecast of the future of the universe, from the return of Halley's Comet to the last light in the cosmos.

In 1962, the US detonated a nuclear weapon in space, which produced an electromagnetic pulse that disabled three low Earth orbit satellites and damaged electrical equipment in Hawaii.

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

Explore the history, structure, and species of Australia's Great Barrier Reef with this interactive journey narrated by Sir David Attenborough.

Plato's famous allegory of the cave is a metaphor exploring the value of truth over ignorance.

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

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.

Explore the wineries of Napa Valley with an interactive map of its hundreds of wineries, vineyards, and tasting rooms.

Explore the history of American restaurants through an archive of menus dating back to the early 1800s.

Joan Didion interviewed The Grateful Dead in 1967, before they became music icons.

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.