Astronomers have obtained the first detailed spacecraft image of an interstellar comet passing through our solar system. The European Space Agency’s Jupiter Icy Moons Explorer, or JUICE, captured a remarkable view of comet 3I/ATLAS, a rare object that originated beyond our solar system and made its closest approach to the Sun in late 2025.
The image, taken by JUICE’s JANUS optical camera while the spacecraft was about 66 million kilometers away, reveals the comet’s glowing coma and surrounding dust, offering fresh insights into its structure and composition, according to the ESA. It marks the first time an interstellar comet has been photographed in such detail by a deep-space mission.
Unlike typical comets that formed within our solar system, 3I/ATLAS traveled from interstellar space, making it an exceptionally rare scientific opportunity. Its precise origin remains unknown, but objects like this are believed to be fragments ejected from other planetary systems. Studying how such bodies react to the Sun’s radiation and gravitational forces can reveal valuable information about their composition and the environments in which they formed.
Courtesy: ESA
Although JUICE was primarily launched to study Jupiter and its icy moons, the unexpected encounter with 3I/ATLAS provided a bonus scientific target. Five of the spacecraft’s instruments participated in observing the comet over several months. In addition to JANUS imaging, ESA’s MAJIS and UVS instruments are analyzing spectrometric data to determine the chemical makeup of the comet’s gases and dust.
By examining how light is absorbed and emitted by the comet, scientists can identify specific molecules and compounds, some of which may differ from materials commonly found in our solar system. Such findings could help researchers understand how planetary systems form across the galaxy and whether interstellar objects carry clues about the building blocks of planets.
Data analysis is still ongoing. After JUICE moved to the far side of the Sun relative to Earth, communication slowed, requiring smaller antennas and reduced transmission rates. More than 120 images and multiple spectrometric datasets are now being processed, with detailed results expected later this year.
For now, 3I/ATLAS offers a rare window into material forged around another star, briefly visiting our cosmic neighborhood before continuing its journey through the galaxy.