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Astronomy

Illustration of a time sequence as the celestial body moves in front of a distant star

This Tiny Celestial Body Past Pluto Shouldn’t Have an Atmosphere—but Astronomers Say They May Have Detected One

Worlds this small and distant are thought to be too cold and have too little surface gravity to hold onto gases. But the findings suggest that icy, rocky objects in the solar system’s outer reaches are more dynamic than we thought

Pluto was considered the solar system's ninth planet for more than 70 years.

Could Pluto Once Again Be Considered a Planet? New Remarks From NASA’s Administrator Highlight an Enduring Debate Among Scientists

Two decades ago, the International Astronomical Union—which defines and names celestial bodies—redefined the criteria for being a planet, putting Pluto into the new category of dwarf planet

The Eta Aquarids as seen from Sri Lanka in 2024

The Eta Aquarid Meteor Shower Peaks This Week, but a Bright Moon Might Spoil the Show

This annual event, which peaks on the night of May 5 into the next morning, comes from the trail of debris left by Halley’s comet. It’s best viewed from the Southern Hemisphere, but skywatchers in the north can catch a glimpse

Tatooine is a fictional desert planet with two suns. No such planet had been found when this scene in Star Wars: Episode IV–A New Hope ​​​​​​was created.

Astronomers Discover 27 Potential Planets Each Orbiting Two Stars, Just Like the Fictional Tatooine in ‘Star Wars’

The findings could more than double our current database of worlds that loop around binary star systems. But researchers need to analyze more data before they can officially celebrate a new trove of far, far away exoplanets

The astrolabe weighs more than 18 pounds.

This Giant 400-Year-Old Astrolabe—Made by Mughal Master Craftsmen and Owned by Royalty—Fetched Millions at Auction

Ancient Greek astronomers and early Islamic scientists used astrolabes as mechanical computers to calculate time, determine height and navigate by the stars

Comet 3I/ATLAS has much more "heavy" water than comets that formed in the solar system, according to a new study.

Interstellar Comet 3I/ATLAS Came From an Extremely Cold, Lonely Region of the Milky Way Galaxy, New Research Suggests

Astronomers analyzed the vapors coming off the comet when it neared the sun and found it had a lot of “heavy” water. That hints it grew up in a frigid planetary system, possibly before its home star formed

A Lyrid meteor photographed in Yunnan Province, China, on April 24, 2022

Look Up This Week to See the Peak of the Lyrid Meteor Shower. Humans Have Documented This Dazzling Annual Display for 2,700 Years

During the wee hours of April 22, moonset times will give stargazers in much of the United States a solid stretch of dark sky before sunrise

Researchers found this hand ax, which appears to have been shaped around a geological feature imprint.

Cool Finds

These Big-Brained Ancestors May Have Loved Crystals Just as Much as Modern Humans Do, According to New Research

Archaeologists in Israel unearthed prehistoric hand axes that Homo erectus crafted from stones including fossils and crystals, perhaps a sign that they wanted to connect with the cosmos

A red aurora over Engaru, Hokkaido, Japan, similar to those documented throughout history, which helped the researchers reconstruct past solar activity

Medieval Writings and Tree Rings Helped Researchers Track a Solar Storm From 800 Years Ago and Reconstruct Past Solar Cycles

Diary entries by the Japanese poet Fujiwara no Teika, along with other historical sources from across Asia and Europe, played pivotal roles in a new study

An artist's concept of comet 41P as it approached the sun, turning some of its ice into gaseous jets

In a First, an Astronomer May Have Witnessed a Comet Stop Its Spin—Then Reverse Its Rotation

Archival images snapped by the Hubble Space Telescope revealed the unusual event

Stars in the ancient dwarf galaxy Pictor II

Astronomers Discover a Rare Primitive Star That Provides a Chemical Snapshot of the Early Universe

PicII-503 is likely a second-generation star, born from the remnants of the very first stars, according to a new study

A green fireball meteor flew above central California on the night of March 22.

Two Green ‘Fireballs’ Streaked Across the West Coast Sky, Some of the Latest in a String of Dazzling Meteors Above the U.S.

Some of the space rocks exploded, causing loud booms, and a piece of one may have crashed into a house

Illustration of L98-59d (lower left) orbiting its host star, a red dwarf

Scientists May Have Discovered a New Type of Planet Beyond the Solar System. The Catch? It Smells Like Rotten Eggs

L98-59d seems to be a molten planet with an atmosphere full of hydrogen sulfide

An artist’s illustration of the exoplanet HD 219134 b, a rocky world about 21 light-years from Earth. This scorching planet, which orbits extremely close to its host star, might have a partially molten surface and volcanoes.

Alien Life Could Look Nothing Like What We Expect. Here’s How Microbes Beyond Earth Might Live Without Liquid Water

Like the lead character of “Project Hail Mary,” some scientists are proposing ways that life might exist beyond a star’s “habitable zone,” often considered the gold standard of potential livability

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A Meteor Streaked Across the Morning Sky as a Dazzling ‘Fireball’ Before Exploding With a Thunderous Boom Above Ohio

A six-foot-wide, seven-ton asteroid caused the rare celestial spectacle

An artist's conception of a magnetar surrounded by a wobbly accretion disk

Astronomers Witnessed the Birth of a Magnetar for the First Time. It Explains the Mysterious Flickering of an Ultrabright Supernova

New research suggests that the highly magnetized remnants of stars are responsible for powering some of the universe’s most brilliant supernova explosions

The Van Allen Probes spent seven years studying two donut-shaped rings of radiation around the Earth.

A 1,300-Pound Spacecraft Might Be Plummeting Through Our Atmosphere Right Now

The debris poses minimal risk of harming anyone

Dimorphos, on the lower right, surrounded by debris moments after DART's collision in September 2022. The asteroid's larger companion, Didymos, is on the left. 

NASA’s Asteroid-Smashing DART Mission Changed a Space Rock’s Orbit Around the Sun, Marking a First for Humanity

Studying the 2022 collision’s effects can help scientists protect the Earth from celestial objects that might head toward us

New data suggest that the asteroid will pass the moon at a distance of 13,200 miles.

Asteroid 2024 YR4 Won’t Slam Into the Moon, According to NASA

Both Earth and the moon will be dodging the infamous space rock in 2032

New images of Uranus show the planet in blue, the upper atmosphere in red, auroras in lighter red spots and rings in white.

Take a Look at Uranus’ Weird, Lopsided Upper Atmosphere Bespeckled with Auroras

A new 3D map of gas surrounding the planet will help researchers better understand the strange world

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