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
Comet 3I/ATLAS is losing water 'like a fire hose' on full blast
Researchers have discovered that interstellar comet 3I/ATLAS has been shedding water, providing insights into the building blocks of life outside of our solar system and the evolution of interstellar comets.
'Closest view' yet of interstellar comet 3I/ATLAS captured by Mars orbiter
The European Space Agency's ExoMars orbiter has captured the closest view yet of the interstellar comet 3I/ATLAS. The images reveal the comet's bright coma but show no signs of a tail.
Interstellar comet 3I/ATLAS may come from the mysterious frontier of the early Milky Way, new study hints
The interstellar comet 3I/ATLAS does not come from our corner of the Milky Way, and may be a time capsule of the early galaxy, new research into its trajectory hints.
Newly discovered comet 'Lemmon' may be visible to the naked eye this month — but it will look more like a lime
Comet Lemmon, discovered earlier this year, will make a close approach to Earth later this month, giving skywatchers the chance to see its surprising lime-green glow.
Skywatching alert! See 2 bright comets on the same night as a meteor shower this October
Comet C/2025 R2 (SWAN) can now be seen with binoculars close to Mars in the western sky after sunset.
Interstellar comet 3I/ATLAS could be turning bright green, surprising new photos reveal
New photos captured during the recent "blood moon" total lunar eclipse show that the interstellar comet 3I/ATLAS may be turning green as it gets closer to the sun.
New photos of comet 3I/ATLAS reveal its tail growing before our eyes
New images reveal interstellar comet 3I/ATLAS beginning to grow a signature tail as it zooms closer to the sun ahead of a close encounter with Earth this fall.
