Interstellar comet 3I/ATLAS is aid in the highlight after a series of most modern observations triggered recent scientific excitement and renewed controversy. In recent days, NASA’s Hubble Dwelling Telescope released a sharper put up-perihelion image, ESA’s JUICE spacecraft returned an unexpected navigation-camera peep exhibiting a pair of tails, and a European compare crew suggested that the comet might possibly well well also be erupting in cryovolcanoes—“ice volcanoes”—on its surface.
In the intervening time, Harvard astrophysicist Avi Loeb revealed original analyses of the most up-to-date Hubble knowledge and shared what he believes the image initiatives.
Hubble’s original image of Interstellar comet 3I/ATLAS
Hubble noticed 3I/ATLAS on 30 November 2025, shooting a teardrop-shaped interior coma extending sunward, an queer “anti-tail.” The glow spans roughly 40,000 km, with a sunward extension of about 60,000 km.
Avi Loeb’s interpretation of Hubble’s original image of Interstellar comet 3I/ATLAS
In his original essay, “A Novel Hubble Dwelling Telescope Image of 3I/ATLAS,” Loeb argues that the November 30 image shows an “anti-tail” stretching some 60,000 km sunward. He hyperlinks this to predictions from his recent paper suggesting that “a excellent-looking out assortment of macroscopic, non-unstable objects” might possibly well occupy separated from the comet on account of non-gravitational acceleration. Per Loeb, this swarm ought to restful appear “roughly 60,000 km nearer to the Sun than the nucleus,” matching the noticed extension.
3I/ATLAS’s ‘ice volcanoes’?
A preprint by Josep M. Trigo-Rodríguez and colleagues argues that 3I/ATLAS might possibly well well exhibit cryovolcanism, constant with spiral-admire jets considered in high-resolution pictures as the comet approached perihelion. The crew proposes that heating of CO₂ ice might possibly well well trigger chemical reactions releasing gas and energy, producing eruptions resembling “ice volcanoes.”
The work remains unreviewed, and astronomers emphasize that upcoming Hubble, JWST and JUICE spectroscopy will likely be well-known for attempting out whether or not these jets require cryovolcanoes—or is also defined by frequent cometary project.
Where is 3I/ATLAS now?
As of December 5, 3I/ATLAS is ready 286 million km from Earth, at magnitude ~12, and transferring from Virgo against Leo. Skilled observers with 12-mosey telescopes might possibly well well judge it intention Regulus in mid-December. This might increasingly stay a faint telescopic goal before fading aid into deep residence.
What’s 3I/ATLAS?
Chanced on in July this year by the ATLAS watch telescope in Chile, 3I/ATLAS (C/2025 N1) is simplest the third confirmed interstellar object ever noticed, after ʻOumuamua and Borisov. It follows a strongly hyperbolic orbit and can leave the Photo voltaic System forever.
Scientists now agree on a lot of basics:
- It has an interstellar origin, with an incoming tempo of ~58 km/s.
- Hubble suggests a nucleus below 1 km, though the coma obscures its appropriate size.
- JWST and floor-based mostly mostly telescopes detect CO₂, water ice, CO, carbonyl sulfide, cyanide and nickel vapour.
- It passed perihelion in unhurried October at ~1.36 AU and poses no possibility to Earth.
- As of early December, it’s about magnitude 12 in Virgo.
