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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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.
'3I/ATLAS is a comet': NASA finally releases new 3I/ATLAS images and addresses alien rumors
NASA's highly anticipated comet 3I/ATLAS images have been released, with a space agency official shooting down alien rumors and stressing that the interstellar visitor is a comet.
Watch live: New images of comet 3I/ATLAS revealed by NASA today (Nov. 19)
NASA will finally share long-awaited images of interstellar object 3I/ATLAS taken during the comet's close flyby of Mars. A live stream has been set for today (Nov. 19).
'From another world': 3I/ATLAS photobombs a galaxy and shows off its multiple tails in stunning new image
An incredible new image shows the multi-tailed alien comet 3I/ATLAS shooting past a distant galaxy in the night sky. The stunning scene is a reminder of the object's perfectly natural interstellar origins, photographer Satoru Murata claims.
Mars orbiter narrows down exact path of interstellar comet 3I/ATLAS
Scientists from the European Space Agency have significantly narrowed down the trajectory of the interstellar visitor 3I/ATLAS thanks to data from the alien comet's recent flyby of Mars, allowing for more accurate future observations.
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.
