Leprosy symptoms may appear 20 years after infection, so contact tracing isn't possible.

Explore Lewis and Clark's 8,000-mile journey in Google Earth.

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

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.'

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

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

Check out some of the best books that can be read in a single day, with titles from Han Kang, Denis Johnson, Muriel Spark, and more.

This interactive website features nearly 40,000 photos from Wikipedia for you to create visual mosaics with.

Computer scientists first started trying to optimize dating using computers in the 1950s.

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.

Washing dishware before putting it in a dishwasher may reduce the appliance's effectiveness because it dynamically adjusts wash time and temperature based on a sensor that detects dirtiness.

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

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.

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.

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

Apeirophobia is the fear of everlasting life and may stem from the human brain's inability to conceptualize the concept of anything happening beyond what it can project out, such as the concept of an infinite life.

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

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.

There are 'YouTube camps' that teach children how to create content for the video platform.

Watch the many different civilizations around the Mediterranean shift power from the year 2500 BCE to 0 BCE in this animated map.

Light takes approximately eight minutes to travel from the sun's surface to Earth, but it takes thousands of years to reach the star's surface from its core—a distance more than 200 times shorter.

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

Explore a collection of famous literary maps, including original images from 'Treasure Island,' 'The Swiss Family Robinson, ' and 'Walden.'

'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.

Humans may have as many as 100,000 to 150,000 individual hairs on our scalps, growing at a rate of roughly 1 centimeter per month.

The world's largest waterfall is in the ocean and is more than three times the height of Angel Falls, the largest waterfall on land.

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

Watch Bruce Springsteen's 1985 performance of Woody Guthrie's 'This Land Is Your Land,' which he calls 'the greatest song ever written about America.'

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

See a 3D reconstruction of Tenochtitlan, the Aztec capital

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

On a cruise ship, the average person uses about 50 gallons of water a day, which is treated by bacteria and onboard filtration systems, then stored until the ship can legally discharge the wastewater.

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

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

Watch footage from the moments the Titanic wreck was discovered by a joint US-French research team in 1985.

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

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

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

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.

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

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.