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 object 3I/ATLAS is about to get very active — Space photo of the week
The interstellar comet 3I/ATLAS is barreling toward its closest point to the sun as perihelion looms on Oct. 29. How different will it look when it reappears on the other side?
New images of interstellar object 3I/ATLAS show giant 'jet' shooting toward the sun
New telescope images show that the interstellar comet 3I/ATLAS is shooting a giant jet of gas and dust toward the sun. This is normal behavior for comets, an expert told Live Science.
Superbright 'Comet Lemmon' gets its tail temporarily torn to pieces by solar wind
An astrophotographer snapped a stunning shot of Comet Lemmon's flowing tail getting shredded by a strong gust of solar wind, just three days before it reaches its closest point to Earth.
Superbright 'Comet Lemmon' flies through auroras over Scotland during surprise solar storm
A photographer snapped a striking shot of Comet Lemmon streaking over Scotland as the night sky unexpectedly filled up with a technicolor mix of vibrant auroras.
Comets Lemmon and SWAN reach their brightest this week
Comet Lemmon (C/2025 A6) makes its closest approach to Earth on Oct. 21, about 24 hours after the fainter Comet SWAN (C/2025 R2) does the same. Here's how, where and when to see them both.
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.
