Friday, May 8

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

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

See photos of Meteora, a mountainous site in central Greece, home to 14th-century monasteries perched atop soaring outcroppings.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

In 1915, workers recovered a submarine-like vessel from the Chicago River, prompting fears of German espionage

Waves off the coast of Nazaré, Portugal, can reach over 100 feet and are caused by the area's deep underwater canyon geography

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

Calculate how much of your tax dollars go to each federal program based on your income, filing status, and number of children

Track the location of the Voyager probes, currently between 13 and 15 billion miles away from Earth.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

The first horror movie is believed to be George Méliès' 1986 short 'The Haunted Castle,' which pioneered the use of special effects

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world

Explore the animals that populate the depths of the ocean, from fish and coral in the first few hundred feet, all the way down to the bottom of the Mariana Trench.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

Neutron stars, the remains of some massive stars after they explode in a supernova, are the densest directly observable objects in the universe.

Existentialist writer Jean-Paul Sartre coined the famous phrase 'Hell is—other people' in his play 'No Exit'

The Mona Lisa's celebrity status and repeated restorations have obscured what made the painting so revolutionary for its time

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

Exploring the Larry Bird punch that almost changed March Madness

See the most iconic photos from four decades of LIFE magazine

Roughly 43 million US borrowers owe roughly $1.7T in student debt, the second-largest source of consumer debt behind mortgages.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

View the ten deadliest tornadoes in US history.

Up to a million Girl Scouts sell about 200 million cookie boxes every spring, generating $800 million, largely because refusing a child is frowned upon

Watch contemporary footage covering the US-backed Shah of Iran fleeing the country in the face of the 1979 Iranian Revolution

Watch a 1934 short film starring jazz legend Cab Calloway, a major figure in the Harlem Renaissance's music scene