The Astronomical Congress designated 88 groups of stars as official constellations

What the stars once meant to ordinary people

The stars were a crucial aid for ordinary human beings in premodern societies, acting as regular timekeeping phenomena and celestial navigators. Today, light pollution and modern technology have rendered the stars a mere aesthetic delight for most of us, but their significance in history remains. Watch this brief video to learn how premodern humans used the stars for navigation, mathematics, and more.

Meet Hipparchus, the Greek astronomer who created the world's first star map

Astronomer Hipparchus created accurate maps of the night sky way ahead of his time, with coordinates sometimes within a single degree of modern values. Hipparchus founded a new theory of star motion, modeling the sky as a celestial sphere with coordinates similar to latitude and longitude—concepts only recently created in Hipparchus' time.

Asteroids were discovered by 18th-century planet hunters

While looking for a planet between Mars and Jupiter to coincide with an apparent mathematical pattern in the distances of known planets from the sun, a group calling themselves the "Celestial Police" discovered multiple objects that fell into a new classification.

The names of comets can change based on subsequent observations

The International Astronomical Union's coded naming system uses the first letter to indicate a comet's category, which can change over time. "D" represents comets that have been lost or broken up, while "A" applies to former comets that are now asteroids or dwarf planets.

The scientific name for northern lights came from two Greco-Roman gods

Although cave paintings may have depicted them millennia earlier, one of the oldest known references to auroras is a Babylonian cuneiform tablet from about 600 BCE. In 1619, Galileo Galilei named the phenomenon in the northern hemisphere "aurora borealis" after the Roman goddess of dawn—Aurora—and the Greek god of the north wind—Boreas.

A map of the Milky Way

Curious about the layout of the cosmos? This resource presents a detailed map of our galaxy, the Milky Way. Learn the basic structure and identify prominent global clusters, nebulae, main arms, spurs, and constellations. With numerous different maps and mediums, get oriented with the universe’s configuration and where exactly we fit into it.

Astronomers use a set of scaffolding methods to measure distances across the universe

Different methods are used depending on how far away an object is—from radar for nearby planets, to parallax for stars, to redshift and supernovae for distant galaxies. These tools allow scientists to chart the universe across unimaginable scales using astronomical units (AU), light-years, and parsecs.

The Hubble Space Telescope is named after astronomer Edwin Powell Hubble

Using the Hooker Telescope at the Mount Wilson Observatory in California in the 1920s, Hubble identified Cepheid variable stars in what was believed to be the Andromeda nebula. These stars can be used to determine distance in space, allowing Hubble to realize that Andromeda was a galaxy of its own.

A data visualization exploring six decades of spacewalks

Astronauts' initial small step for mankind may standout, but how many steps have we taken so far? Space and moonwalks further our understanding of spaceflight, celestial bodies, and space itself. Created to resemble a constellation map, this chart...

A 1919 eclipse validated general relativity and made Albert Einstein a celebrity

According to the theory, starlight should deflect around massive objects due to the warping of spacetime light travels through on its way to Earth. Comparing the locations of stars behind the Sun during the eclipse with their positions at night showed deflections that popularized Einstein's model.

The most mysterious (known) star in the universe

Something massive, with roughly 1,000 times the area of Earth, is blocking the light coming from a distant star known as KIC 8462852. One of astronomers' more intriguing theories: Alien technology. Discovered via NASA's Kepler space telescope and a...

UK's Royal Astronomers join the hunt for Ramadan's crescent moon

In Britain, Muslim communities and professional astronomers now collaborate to officially spot the moon that begins Ramadan, blending ancient practice with modern science. The partnership culminates in a live, unscripted annual broadcast even.

Stellar photos from around the world of the 2020 Perseids

The annual Perseids meteor shower occurs in the Northern Hemisphere's summer, peaking usually around mid-August. The phenomenon is caused by the Earth's passing through a comet's debris trail of ice and dust, providing a weekslong spectacle for...

The winter solstice has been celebrated globally for millennia

From gatherings at Stonehenge in the UK to celebrations of the triumph of Mithra in Iran, cultures around the world have marked the shortest day of the year in a variety of ways for a very long time. Here are eight known to us today that endure.

The Star-Spangled Banner was the name of a massive flag at Fort McHenry

Designed and fabricated by flagmaker Mary Pickersgill, the flag has 15 stars and 15 stripes and was 30 feet by 42 feet, a size big enough to be seen by Francis Scott Key, who was eight miles away from Fort McHenry when he began composing his poem.

Where did the term ‘astronaut’ come from?

Astronaut essentially translates to space sailor, though these sailors may be referred to differently depending on their home country. For example, Russian star sailors are called cosmonauts. Though why American, European, Canadian, and Japanese...

Disneyland's drinkers once had their own unofficial mascot

Disney has countless subcultures and unofficial fan clubs, including D3, also known as the Disney Day Drinkers. Founded in 2021, the club began informally meeting near a trashcan, nicknamed Binny, in Disney World’s Epcot park … until it mysteriously disappeared in 2023.

See the 25 of the best photos of auroras from around the world.

Meteorological v. astronomical seasons, explained

Meteorologists and climatologists define seasons differently from “regular” or astronomical spring, summer, fall, and winter. Traditional seasons reflect the movement of celestial objects, known as the astronomical seasons; meteorologists mark seasonal change based on temperature averages.

See a list of six famous people with animals named in their honor

The bird Polioptila attenboroughi, the spider Spintharus barackobamai, and the water beetle Grouvellinus leonardodicaprioi are just a few of the creatures named after celebrities.

The Milky Way only has a 50-50 chance of merging with the Andromeda galaxy

Previously considered a near certainty, research data from Hubble and GAIA have reduced the likelihood of a collision and merger between the two galaxies. Instead, the data suggests the Milky Way will absorb the Large Magellanic Cloud, a dwarf galaxy, in the next two billion years.

The legend of the Chinese zodiac involves a race between animals

The legend of the Chinese zodiac says that to help people keep time, the emperor of the gods established a 12-year cycle, with each year symbolized by a different animal. To choose the animals, he held a cross-river race. Each of the winning animals used their unique skills to get across the river: The snake is sneaky, the rabbit is nimble, and the rat is cunning. These characteristics are believed to be mirrored by those born under the animals’ zodiac signs.

James Webb telescope shows new views of Uranus

Following in the footsteps of the Neptune image released in 2022, NASA’s James Webb Space Telescope has taken a stunning image of the solar system’s other ice giant, the planet Uranus. The new image features dramatic rings as well as bright features in the planet’s atmosphere.

The Big Ten is the oldest Division I collegiate athletic conference in the US

Established in 1896 with seven members, the Big Ten has expanded far beyond its Midwestern roots. As of 2024, it includes 18 schools—stretching coast to coast from Rutgers in New Jersey to UCLA in California.

Stars appear to twinkle because turbulence in the motion of molecules in Earth's atmosphere causes light to bend and wiggle rapidly on its way to the surface—a phenomenon called scintillation.

August A. Busch, Sr. was gifted a six-horse Clydesdale hitch to celebrate Prohibition’s end

This helped reveal the marketing power of a horse-drawn beer wagon, so it invested in a second six-horse Clydesdale hitch. The Clydesdales soon went to New York, where they drew a crowd of thousands en route to the Empire State Building. Anheuser-Busch even gifted a case of Budweiser to New York Governor Alfred E. Smith in thanks for his help in the fight against Prohibition.

A New York fireworks ban necessitated a new way to ring in the New Year

In 1906, the city banned fireworks displays, forcing the Times Square celebration to find a new centerpiece. The Times commissioned Jacob Starr, a Ukrainian immigrant who worked for Strauss Signs, to develop an ornament. He returned with the now-iconic New Year’s ball.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

The first image of a black hole was captured by creating an Earth-sized virtual observatory from a network of eight radio telescopes.

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

One disco producer saw 'Star Wars' four times on its opening weekend and was so inspired that he recorded the album 'Star Wars and Other Intergalactic Funk,' which produced a chart-topping single.

Dozens of S&P 500 stocks, including Coca-Cola and Walmart—known as the dividend aristocrats—have increased dividends every year for 25 years

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

Meet the 56 signers of the Declaration of Independence—most of whom didn't put pen to paper until August 2, 1776—and see their original signatures.

See 33 images that became central to huge scandals, including a young Charles and Camilla, Michael Jackson's baby on a hotel balcony, and Hugh Grant's mugshot.

See how Budweiser's famous Clydesdales spend their days at Warm Springs Ranch, where roughly 70 to 80 of the beer brand's giant horses can be found at any given time.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

Jimmy Carter signed a 1978 bill that legalized home brewing, a move credited with kick-starting the craft beer industry.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

The Brothers Grimm were lawyers before they were storytellers, and became interested in fairy tales as they began investigating how rules and customs had been passed down through cultures.

Browse a detailed visual analysis of over 200,000 similes—comparisons that often use 'like' or 'as'—from popular fiction to see how frequently writers the same idiomatic expressions.

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.

Famed poet TS Eliot rejected the manuscript for George Orwell's political fable 'Animal Farm,' writing that its criticism of authoritarianism was not 'the right point of view.'

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by over 1.5 million Muslims.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

Ebola species have historically been named after where they were discovered, stigmatizing residents who live there, including Bundibugyo, in Uganda.