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

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.

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

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.

As part of the up to 15 pounds of seafood they consume daily, sea otters eat urchins that feed on kelp forests—sources of shelter and food to over 800 species—thereby making the marine mammal a keystone species.

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

Cats have a mutation that prevents them from tasting sweetness, and goldfish rank among the world's supertasters.

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

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

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

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.

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

See a 3D reconstruction of Tenochtitlan, the Aztec capital

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

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

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

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

On planets in systems with two stars, such as the fictional Tatooine from 'Star Wars,' observers would see overlapping rainbows and double rainbows.

Watch an animated visualization of how the Large Hadron Collider works, including how particles are accelerated through a series of machines and how collision data is collected and distributed worldwide.

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.

If a source of music traveled past someone at twice the speed of sound, assuming sufficiently sensitive hearing and powerful equipment, they would hear the music backward.

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

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

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.

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

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.

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

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.

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.'

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.

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

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.

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

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

See a breakdown of how some of the most common food items are traded across the globe, including the key trade relationships for each item.

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

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

Explore (and debunk) the world's most contagious misconceptions—from the 5-second rule to sugar rushes—on this interactive site. Click on each misconception for further evidence.

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.