The Manhattan Project created secret cities that didn’t appear on maps

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

'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.

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.

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.

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.

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

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

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.

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

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.'

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

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

Here are some tips from Pew Research to help you distinguish between a good poll and an unreliable one.

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

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

Between 2002 and 2012, at least 12 people were killed in the Philippines in incidents related to off-key karaoke singing of Frank Sinatra's 'My Way.'

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.

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

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

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

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.

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

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

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.

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.

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

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

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

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.

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

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

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.

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 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.

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.

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.

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

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