Initial analysis suggested the nucleus was approximately 13.7 kilometers wide (roughly city-sized); however, researchers believe this may have been an overestimate. It is likely a long-period comet ...

First its rotation slowed between March and May 2017, taking 46 hours to complete a spin where it had once taken only 20 hours. This occurred as the comet neared its closest point to the sun, roughly ...

The Gemini North telescope snapped a spectacular view of Comet C/2025 K1 (ATLAS) breaking apart as it emerged from the other side of the sun in October.

An instrument aboard NASA’s Europa Clipper spacecraft captured rare ultraviolet observations of an interstellar comet while Earth-based telescopes were blinded by the Sun. The spacecraft’s unique ...

STUNNED astronomers have spotted a new comet out in space – and it this could be a pretty special one. There’s a chance it’ll ...

The comet 3I/ATLAS arrived in the solar system with a reputation for being unruly, but its latest trick has stunned even seasoned researchers. Instead of behaving like a dusty snowball, this ...

Comets are famous for making brief, dramatic appearances in our skies, but one icy wanderer just received an unprecedented level of attention from one of NASA's newest spacecraft. For nearly 40 days, ...

Interstellar comet 3I/ATLAS made its closest approach to Earth on Friday, Dec. 19. The comet will remain about 170 million miles from our planet and poses no danger. While not visible to the naked eye ...