Comet 3I/ATLAS blasts a jet towards the sun in new telescope image

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Space
Comet 3I/ATLAS blasts a jet towards the sun in new telescope image
Elizabeth Howell
Fri, October 24, 2025 at 2:30 PM EDT
3 min read



A recent image of Comet 3I/ATLAS taken by the Gemini North telescope in Hawaii (background), alongside a new Two-meter Twin Telescope image of a jet erupting from the comet in the direction of the sun (inset). | Credit: International Gemini Observatory/NOIRLab/NSF/AURA/K. Meech (IfA/U. Hawaii) / Image Processing: Jen Miller & Mahdi Zamani (NSF NOIRLab) Inset: Teide Observatory, M. Serra-Ricart, Light Bridges


An interstellar comet is dramatically jetting off ice and dust into space, a new image shows.

The comet, called 3I/ATLAS, is sending out a jet of material towards the sun as our nearest star warms up some of its surface. The composite image shows the nucleus or icy, rocky central core of 3I/ATLAS as a large and black dot, along with a white glow — the comet's coma, or atmosphere. The jet is marked in purple and is blasting off towards the direction of the sun, which is typical behavior of comets in the solar system as well.

3I/ATLAS is only the third known interstellar object that has come through our solar system, and is rapidly hurtling towards the sun for its closest approach on Oct. 30. The comet will come within 1.8 astronomical units (sun-Earth distances) of our planet, making it visible in small telescopes before disappearing again into the dark.

Astronomers received notice of the jet Oct. 15 in the Astronomer's Telegram, an announcement service for the astronomy community with editor-in-chief Robert Rutledge, an associate professor at Montreal's McGill University.

Footage of the jet was captured on Aug. 2, and combines 159 exposures of 50 seconds each. It was taken with the Two-meter Twin Telescope at Teide Observatory in Tenerife, which is in the Canary Islands.

"This is the usual," Miquel Serra-Ricart, astrophysicist and chief science officer at the Light Bridges private research institution, which co-manages Teide, told our sister site LiveScience in an email. Serra-Ricart was the individual who posted the new images, which are not yet peer-reviewed; he pointed out that the comet’s tail is also pointing away from the sun, which is typical of these icy objects.

While comets do warm up when they get close to the sun, they don't warm up in all spots in the same fashion. The areas facing the sun heat up fastest, and if there is a weaker area on the surface of the comet, sublimated gases under the surface can burst through — causing these sun-facing jets.



A view of comet 3I/ATLAS taken by the Gemini South Telescope. | Credit: International Gemini Observatory/NOIRLab/NSF/AURA/Shadow the Scientist. Image Processing: J. Miller & M. Rodriguez (International Gemini Observatory/NSF NOIRLab)/T.A. Rector (University of Alaska Anchorage/NSF NOIRLab)/M. Zamani (NSF NOIRLab).


Serra-Ricart estimated the jet could be as far as 6,200 miles (10,000 km) from 3I/ATLAS' surface, which is more than twice the equivalent distance across the largest part of the United States. The jet is likely made up of carbon dioxide and dust particles—just like what was spotted by NASA's James Webb Space Telescope back in August.

These jets can begin to fan out as the nucleus of the comet rotates. Some of the material will stay in the coma, while the rest will fall into the comet's tail after pressure from the sun — known as the solar wind — forces it there. Solar system comet C/2020 F3 NEOWISE, which was visible to the naked eye, showed just that kind of behavior back in 2020 in Hubble Space Telescope images.

https://www.yahoo.com/news/articles/comet-3i-atlas-blasts-jet-183000094.html