Comets are "snowballs" of ice and dust that formed during the birth of our solar system and have orbited the sun since. Live Science brings you the latest comet news, features and articles as astronomers track these extraordinary objects. From the city-sized comet that grew "horns" to the mega comet that may be the largest seen in recorded history, our expert writers and editors will tell you everything you need to know about them, and how to observe them when they're visible from Earth.
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Latest about Comets
New image of 'other comet ATLAS' reveals it's breaking apart ahead of close approach to Earth
New images show that comet C/2025 K1 (ATLAS) has fragmented after passing its closest point to the sun, ahead of its close approach to Earth later this month. This is not the interstellar comet 3I/ATLAS.
Astronomers detect first 'radio signal' from interstellar comet 3I/ATLAS — but it wasn't aliens
Astronomers at South Africa's MeerKAT radio telescope have detected the first radio waves coming from the interstellar comet 3I/ATLAS. But while this sounds suspiciously like alien activity, it is actually further proof of its completely natural origins.
No, comet 3I/ATLAS hasn't exploded — and no, that doesn't mean it's an alien spaceship
Comet 3I/ATLAS appears to be normal and intact, despite some reports that the interstellar visitor exploded after its brush with the sun.
New 'nearly interstellar' comet — wrongly linked to 3I/ATLAS — will reach its closest point to Earth on Tuesday (Nov. 11)
Newly discovered comet C/2025 V1 (Borisov), which has some minor similarities to 3I/ATLAS, will make its closest approach to Earth on Tuesday (Nov. 11). However, despite recent rumors, the two objects are not related to one another.
Irradiated Comet 3I/ATLAS glows green and hides its tail in new image
A researcher has captured comet 3I/ATLAS glowing green and hiding its tail in a new image from the Lowell Observatory's powerful Discovery Telescope as we enter a critical observation phase for the interstellar visitor.
There's another comet ATLAS in our solar system — and it just turned gold after a perilous dance with the sun
New photos show that the recently discovered comet C/2025 K1 (ATLAS) developed a surprising golden glow after reaching its closest point to the sun. Until now, the comet has gone under the radar, largely thanks to the more famous interstellar comet 3I/ATLAS.
'Interstellar visitor' 3I/ATLAS may have just changed color — for the third time
Recent observations of the interstellar object 3I/ATLAS show that it has developed a faint blueish hue, hinting at a potential color change. This is the third time experts have seen the comet's coloring shift since it was discovered.
Astronomer reveals first look at Comet 3I/ATLAS as it reappears from behind the sun
An astronomer has snapped comet 3I/ATLAS using the Lowell Observatory's powerful Discovery Telescope, as well as his own small telescope. The new photos are believed to be the first optical observations of the interstellar visitor since it disappeared behind the sun.
Comet 3I/ATLAS has been transformed by billions of years of space radiation, James Webb Space Telescope observations reveal
The interstellar comet 3I/ATLAS has a thick irradiated crust that no longer resembles its home star system, simulations and James Webb Space Telescope observations have found.
NASA spacecraft reveal interstellar comet 3I/ATLAS brightened rapidly as it swooped behind the sun
Interstellar comet 3I/ATLAS is briefly out of view as it travels around the sun this week, but researchers and amateur astronomers used spacecraft data to track its progress right up until perihelion.
