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A stunning new image of interstellar comet 31/ATLAS has revealed that its once-vanished ion tail has dramatically reappeared — and is now longer, brighter, and more structured than ever before. 

The new observation, captured by the Virtual Telescope Project, adds a surprising twist to the unfolding story of this rare interstellar traveler.

A Rare Glimpse of an Interstellar Visitor

The image, taken at 11:31 p.m. EDT on Nov. 10 (0431 GMT on Nov. 11), consists of 18 long-exposure frames captured by robotic telescopes in Manciano, Italy.

Despite the comet’s low position — only 14 degrees above the horizon — and interference from a 61% illuminated Moon, the resulting photo shows a sharply defined and luminous ion tail stretching across the sky.

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• New interstellar object 3I/ATLAS — Everything we know about the rare cosmic visitor | Space
• Interstellar comet 3I/ATLAS's tail is still growing, new image shows
• 3I/ATLAS: Interstellar Comet Speeds Up, Turns Blue, Loses Tail, Leaves Experts Stumped

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Initially: 3I/ATLAS Loses Its Tail

Earlier in the comet’s journey, astronomers were baffled when 3I/ATLAS appeared to lose its tail entirely after passing near the Sun.
Harvard astrophysicist Avi Loeb noted that about 13% of the comet’s mass “should appear as a tail, but no such tail is visible.”

The disappearance of a tail — a typically predictable feature of comets heated by solar radiation — stunned researchers. But now, only weeks later, the comet’s activity has surged.

31/ATLAS Grows a New Tail

“Exploiting the unusual good weather of this season, we imaged the interstellar comet again, recording a much more developed ion tail,” said Gianluca Masi, founder of the Virtual Telescope Project.

 “Looking at the picture, we see how the ion tail of 3I/ATLAS is clearly showing better and better.”

An ion tail forms when the Sun’s ultraviolet radiation strips electrons from gases emitted by the comet. These charged particles are swept directly away from the Sun by the solar wind, creating a long, straight, bluish tail distinct from a dust tail.

The new image shows:

• A bright core and compact coma
• A sharply defined ion tail stretching roughly 0.7 degrees
• A faint anti-tail extending in the opposite direction
  

This renewed activity suggests increased sublimation of carbon dioxide and dust, hinting at the comet’s unique composition.

Why 31/ATLAS Matters

3I/ATLAS is only the third confirmed interstellar object, following 1I/‘Oumuamua (2017) and 2I/Borisov (2019).

“If confirmed, it will be the third known interstellar object… providing more evidence that such interstellar wanderers are relatively common in our galaxy,” said Mark Norris, Senior Lecturer in Astronomy at the University of Central Lancashire.

NASA and ESA will continue tracking 3I/ATLAS as it heads toward Jupiter in March 2026, offering astronomers an unprecedented opportunity to study how interstellar comets behave near the Sun.