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Astrophysics

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

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

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

A violent, swirling storm on Jupiter captured by NASA's Juno spacecraft

Lightning Strikes on Jupiter Are 100 Times as Powerful as Those on Earth, a New Study Suggests

Scientists finally have a clearer picture of the gas giant’s intense storms

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

The antimatter went on a roughly 30-minute road trip.

In a First, the World’s Most Expensive and Volatile Substance—Antimatter—Traveled by Truck

The work paves the way for longer-distance transport of the rare material so scientists can study it at other facilities

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

The researchers used sound waves to levitate tiny glass spheres as part of their study. 

Scientists Make a Major Breakthrough in Solving a Hair-Raising Mystery About Static Electricity

The findings can help explain the physics behind phenomena like volcanic lightning

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

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

Some scientists suspect that microorganisms can hop between planets by jumping aboard debris kicked up by asteroid strikes.

Could Life on Earth Have Descended From Microbes That Traveled From Mars Long Ago?

Scientists demonstrated that an Earthly extremophile might withstand being ejected from the Red Planet on debris spewed into space due to an asteroid strike

An artistic rendering of the 'inside out' solar system

Astronomers Discover an Exoplanet in the Wrong Place, Hinting at a Planetary System That Was Born ‘Inside Out’

A rocky planet was found orbiting its host star in an unusual location

An artist's rendition of an imploding star, surrounded by expelled gas and dust shown in red

A Star Suddenly Brightened, Then Faded Into Darkness. Astronomers Say It May Have Turned Into a Black Hole

If confirmed, this disappearing act might provide the closest and best observational evidence for the birth of a black hole

The particle collider smashes together atomic nuclei—comprised of particles called protons and neutrons—to break them into their smaller components.

The U.S.’s Only Particle Collider Recreated Moments From the Early Universe. Now, It Has Closed—to Make Way for a New Instrument

The end of the facility’s 25-year run is “bittersweet”

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