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
Interstellar comet 3I/ATLAS makes closest pass of Earth. Where's it heading next?
Everyone's favorite interstellar comet, 3I/ATLAS, flew past Earth overnight, coming within about 168 million miles (270 million kilometers) of our planet.
Comet 3I/ATLAS reaches its closest point to Earth tonight: How to see it
Comet 3I/ATLAS, the third interstellar object ever detected, reached its closest point to Earth overnight from Thursday to Friday (Dec. 18 to 19), and it remains in a good viewing position tonight. Here's how to see it.
NASA eyes 3I/ATLAS with alien-hunting Clipper spacecraft in new image
NASA's alien-hunting Europa Clipper spacecraft took seven hours of ultraviolet observations of interstellar comet 3I/ATLAS while both objects zoom toward Jupiter.
The UN's International Asteroid Warning Network is closely watching comet 3I/ATLAS. Here's why.
Tracking comets accurately is hard. A new effort with the U.N. and NASA aims to better chart these visitors using 3I/ATLAS.
Comet 3I/ATLAS is getting greener and brighter as it approaches Earth
New images taken with the Gemini North telescope in Hawaii confirm that the interstellar comet 3I/ATLAS has gotten brighter and greener since its close flyby of the sun in October.
New 3I/ATLAS images show the comet getting active ahead of close encounter with Earth
NASA and ESA both shared new images of the interstellar comet 3I/ATLAS this week, as the agencies gear up for the mysterious object's closest approach to Earth on Dec. 19.
RIP 'other ATLAS': Watch the doomed comet explode into pieces in incredible new images
Stunning new photos show the pieces of the "other ATLAS," C/2025 K1, breaking apart in space after the golden comet suddenly exploded earlier this month.
Comet 3I/ATLAS gallery: See NASA's long-awaited images of interstellar visitor
NASA's treasure trove of new comet 3I/ATLAS images provides hotly anticipated views of the interstellar visitor, including from Mars and the sun.
