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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3I/ATLAS is 7 miles wide — the largest interstellar object ever seen — new photos from Vera C. Rubin Observatory reveal
Detailed photos from the newly operational Vera C. Rubin Observatory have revealed that the recently discovered interstellar object 3I/ATLAS is roughly 7 miles wide, making it the largest of its kind ever seen.
Interstellar comet 3I/ATLAS transforms into a giant 'cosmic rainbow' in trippy new telescope image
New photos, including a striking technicolor timelapse, show off the newly discovered interstellar object 3I/ATLAS as it shoots toward us through the solar system.
'Interstellar visitor' 3I/ATLAS could be the oldest comet ever seen — and could grow a spectacular tail later this year
New simulations have narrowed down where the newly discovered interstellar comet 3I/ATLAS likely came from, revealing it could be more than 3 billion years older than the solar system.
Astronomers are racing to study our solar system's newest 'interstellar visitor.' Here's why.
Astronomers have been given the rare opportunity to study an extrasolar object after the recent discovery of the interstellar comet 3I/ATLAS. Experts tell Live Science how they are planning to observe the cosmic visitor.
3I/ATLAS: Everything you need to know about the new 'interstellar visitor' shooting through the solar system
Astronomers have spotted a new interstellar object — the third of its kind ever seen — shooting towards us through the solar system. Here's everything you need to know about 3I/ATLAS.
Watch newly discovered 'interstellar visitor' 3I/ATLAS shoot toward us in first livestream
You can see the recently identified "interstellar object" 3I/ATLAS shooting towards us through the solar system in a livestream from the Virtual Telescope Project.
NASA confirms that mysterious object shooting through the solar system is an 'interstellar visitor' — and it has a new name
Experts have confirmed that the mysterious object hurtling towards us, previously dubbed A11pl3Z, is an "interstellar object." The cosmic interloper, officially named 3I/ATLAS, is only the third of its kind ever seen — and will shoot past Earth later this year.
Newly discovered comet SWAN just 'erupted' with a bright, icy burst. Is it a cold volcano?
Photos show that comet C/2025 F2 (SWAN) experienced a "major eruption," causing it to become temporarily brighter. However, it's still unclear whether the icy object is a true "cryovolcano."
Amateur astronomer discovers bright green comet SWAN25F — and you can see it too
Comet SWAN25F was discovered using photos from the European Space Agency's SOHO spacecraft and can currently be spied using backyard equipment — but it could also become visible to the naked eye in the next few weeks.
Space photo of the week: The last view of the 'Great Comet of 2025' for half a million years
Beautifully captured against a starry sky, Comet C/2024 G3 (ATLAS) — dubbed by some as the "Great Comet of 2025" — shines brightly after its last approach to the sun for hundreds of thousands of years.
