Sea stars are invertebrates—they lack a backbone—and while most exhibit pentametric radial symmetry due to having five arms radiating from a central disk, some can possess more than 40.

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.

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

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

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

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.

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.

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.

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.

Metamorphosis evolved over millions of years as species that hatched as smaller versions of adults started exhibiting genetic mutations that differentiated juvenile and adult bodies.

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

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

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

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

Explore how the most commonly used words in the English language have changed from the 1950s to 2023.

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

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

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.

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.

'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.

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

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

Semaglutides, which belong to a class of drugs called GLP-1s, are prescribed for weight loss in combination with diet and exercise because they trigger the release of the appetite-suppressing hormone incretin.

'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.

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.

Abraham Lincoln had to sneak into Washington, DC, in disguise for his 1861 inauguration after a detective uncovered a plot to assassinate him in Baltimore.

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.'

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.

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

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

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

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.

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

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.

Watch 4-plus decades of Pixar's opening logos.

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.

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.

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

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.