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Comets

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

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

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

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

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

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

A supermoon rises over Washington, D.C., on December 3, 2017.

The Year’s First Bright Supermoon and the Colorful Quadrantid Meteor Shower Coincide This Weekend

The dual celestial events will ring in the new year, although the luminous “wolf” supermoon may hamper skywatchers’ view of the shooting stars

Look up throughout the year to catch a wide array of astronomical sights.

Don’t Miss These Ten Celestial Events in 2026, From Aligned Planets to a Total Solar Eclipse

The upcoming year will offer a blood-red moon, spectacular meteor showers and the first glimpse of the sun’s corona since April 2024

In 2025, researchers watched an interstellar comet, learned about human origins and traced the spread of measles.

The Ten Most Significant Science Stories of 2025, From Medical Breakthroughs to an Interstellar Visitor

All year long, these moments captivated the public, demonstrated dangerous trends, and pushed research and innovation forward

NASA’s Lucy spacecraft, which is investigating a group of asteroids that share Jupiter's orbit around the sun, snapped this image on September 16 as 3I/ATLAS approached Mars. 

Interstellar Comet 3I/ATLAS Is About to Make Its Closest Approach to Earth. Here’s How to View It With Binoculars or a Telescope

On December 19, avid skywatchers can catch a glimpse of the mysterious visitor through powerful binoculars or a telescope when it’s around 170 million miles from our home planet

Elihu Vedder's 19th-century painting "Star of Bethlehem"

The Bible’s Star of Bethlehem May Have Been a Comet, Analysis of Ancient Records Suggests

An odd star brightened for more than 70 days in 5 B.C.E., according to a Chinese text. The object may have been a comet that looked like it rose, then stood still over Bethlehem

The Geminid meteor shower in 2017

The Year’s Best and Brightest Meteor Shower Peaks This Weekend. Here’s How to Watch the Radiant Geminids

A waning crescent moon should make for a fairly dark sky, allowing viewers to see up to 150 shooting stars per hour

This image was captured by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter in October. 

More Than a Dozen NASA Spacecraft Have Glimpsed Interstellar Comet 3I/ATLAS. Now, You Can View New Images That They Captured

The space agency got a close look at the interstellar visitor over the past few months as it zipped by Mars and the sun

The 1999 Leonid meteors as seen from the Leonid Multi-Instrument Aircraft Campaign

Dark Moon, Shooting Stars: How to Catch the Stunning Leonid Meteor Shower This Weekend

A waning crescent moon will offer stargazers an optimal viewing experience this year, with 10 to 15 meteors visible each hour from Sunday into Monday

The European Space Agency’s ExoMars Trace Gas Orbiter captured images of 3I/ATLAS on October 3.

A Rare Interstellar Comet Just Flew by Mars—Here Are the Photos Captured by an Orbiting Spacecraft

The images offer the closest view yet of comet 3I/ATLAS, famous for being only the third known interstellar object to pass through our solar system

Comet C/2025 A6 (Lemmon) moves closer to the sun, as captured on October 2.

Here’s How to See Two Comets and a Meteor Shower Light Up the Sky This Month

Skywatchers are anticipating prime viewing conditions for an annual showing of shooting stars and two comet flybys

The Hubble Space Telescope captured this image of 3I/ATLAS with its Wide Field Camera 3.

Telescopes Reveal Surprising Chemistry of a Rare Interstellar Object Passing Through Our Solar System

Called 3I/ATLAS, the object is only the third of its kind known to astronomers, and it’s likely been heading our way for billions of years, carrying pristine material from another star system

This year, a nearly full moon will make observing the Perseids harder. Here, a meteor is seen on August 3, 2025, in Spruce Knob, West Virginia.

The Popular Perseid Meteor Shower Will Peak This Week—Here’s How to Watch, Despite a Bright Moon

A waning gibbous moon will impact viewing the shooting stars, but the famous meteor shower is still worth observing

The Hubble Space Telescope captured this image of comet 3I/ATLAS on July 21. 

See the Sharpest Image Yet of an Interstellar Comet Passing Through the Solar System

Data from the Hubble Space Telescope unveils new information about this mysterious visitor

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