The Hubble Space Telescope has taken its initial shots of comet 3I/ATLAS, a comet visiting us from beyond our solar system that recently fell apart — but not before it struck a pose for the cameras. It’s only the third such object ever known, after 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019. The subject of numerous scientific tweets and some frantic searches by astronomers anxious to figure out just what it is — and where it came from — before it is gone into the pitch black of deep space forever, 3I/ATLAS was first sighted by the ATLAS survey telescope on July 1, 2025.
Ancient Interstellar Comet 3I/ATLAS Offers Clues to Planetary Systems Beyond Our Own
According to As per Space.com, recent studies indicate that 3I/ATLAS could be some 7 billion years old, well beyond the 4.6 billion years of our solar system. That’s an indication that the comet arose in the more ancient parts of the Milky Way, which would give researchers a rare glimpse of what the early days of other planetary systems were like. Undergraduate researcher Astrafoxen first flagged the Hubble images on Bluesky, noting the comet’s “nice and puffy” coma, despite interference from cosmic rays.
A newly available preprint paper has already revealed that 3I/ATLAS contains abundant water ice and a dust makeup resembling D-type asteroids—organic-rich bodies typically found in the outer solar system. Unlike ultrared trans-Neptunian objects, D-types are believed to have high carbon and silicate content, potentially shedding light on the comet’s deep-space origins and volatile chemistry.
The comet 3I/ATLAS was discovered just as the Vera C. Rubin Observatory was gearing up to carry out its initial observations of the heavens, dovetailing with the LSST’s expected discovery of many more interstellar objects in the coming decade.
Until then, 3I/ATLAS holds the astronomical spotlight. Its brief solar system passage offers a precious opportunity for researchers to analyse the material makeup of alien planetary systems. The Hubble images, now available for download, are expected to aid future papers as scientists continue to unravel the story of this ancient cosmic traveller.