Comet 3I/ATLAS Flaunts Bright Halo and Tail in New Image Taken by Jupiter-Bound Spacecraft
Although comet 3I/ATLAS has disappeared, it will remain an influential research topic for the foreseeable future. As the interstellar comet passed in front of the Sun and Earth in late 2025, several spacecraft studied its behavior and composition. Since then, a steady stream of data has been coming back to Earth-based scientists trying to interpret the mysterious nature of 3I/ATLAS.
The latest glimpse of 3I/ATLAS has just arrived, revealing the comet’s trajectory just a week after its closest approach to the sun on October 29-30, 2025. An image taken by the European Space Agency’s Jupiter Icy Moons Explorer (Juice) shows the telltale features of 3I/ATLAS, including its tail and gas layer. Similar images, now in the hands of ESA scientists, could soon clarify what differentiates 3I/ATLAS from classic comets.
Learn more: Another ATLAS comet appears fragmented after close encounter with the Sun
A snapshot of Comet 3I/ATLAS
Comet 3I/ATLAS photographed from Juice — a mission en route to explore Jupiter’s icy moons.
(Image credit: ESA/Juice/JANUS/CC BY-SA 3.0 IGO)
Throughout the second half of 2025, comet 3I/ATLAS piqued the curiosity of scientists and the general public. The comet’s journey inspired a whirlwind of studies and theories that sought to answer many questions; everyone wondered where the interstellar visitor came from and desperately wanted to know what it was doing in our solar system.
Scientists were quick to assure that 3I/ATLAS posed no threat to Earth, confirming that it was simply a comet, and nothing more. They monitored the comet’s path until it came closest to Earth on December 19, 2025, about 270 million kilometers (168 million miles) from our planet.
Several spacecraft observed and captured images of 3I/ATLAS as it hurtled through space. The last image of Juice, taken on November 6, 2025, helped ESA scientists understand how the comet was moving relative to the sun.
In the upper left corner of the image, two arrows indicate the direction in which the comet was moving (blue) and the relative direction of the sun (yellow), according to a press release.
Review Juice data
ESA’s Juice spacecraft was launched in April 2023 on a mission to explore Jupiter and its three large oceanic moons (Ganymede, Callisto and Europa). But as luck would have it, the spacecraft also managed to gather key details about 3I/ATLAS.
The November image was taken by JANUS, a multicolor optical camera on Juice. At the time the image was taken, Juice was approximately 66 million kilometers (41 million miles) from 3I/ATLAS.
The image shows 3I/ATLAS enveloped in its coma, a bright cloud of icy gas and dust emitted from the comet’s nucleus. A tail moving away from the comet is also visible.
According to ESA, JANUS has taken more than 120 images from 3I/ATLAS, which are currently being examined by scientists. The images are joined by data collected by Juice with four additional science instruments: MAJIS (Moon and Jupiter Imaging Spectrometer), SWI (Submillimeter Wave Instrument), PEP (Particle Environment Package), and UVS (a UV Imaging Spectrograph).
The unsolved secrets of 3I/ATLAS
The data collected by Juice was recently transmitted back to Earth; the spacecraft had to use a smaller, medium-gain antenna to send it, because its high-gain main antenna already served as a heat shield.
ESA research teams will analyze data and images from Juice to understand 3I/ATLAS and its capabilities. So far, the comet’s behavior appears to be that of a normal comet, according to the ESA.
However, the composition of 3I/ATLAS is another story; scientists had previously discovered that the comet contained an abundance of nickel, but not iron, according to a 2025 preprint report in the Letters from astrophysical journals. Additionally, the ratio of carbon dioxide to water in his coma is exceptionally high, according to a separate pre-printed ratio in the Letters from astrophysical journals. Further studies of these traits could shed light on where and how 3I/ATLAS formed.
More answers will come at the end of March, when all of ESA’s instrument teams meet to review their findings.
Learn more: New images of comet 3I/ATLAS reveal ‘how magical the universe could be’
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