Mysterious Comet 3I/ATLAS Stuns Scientists After Losing Its Tail, What’s Really Going On?

The mysterious interstellar object 3I/ATLAS has once again surprised astronomers after recent images revealed that it appeared without a tail, something highly unusual for a comet-like body passing close to the Sun.

Normally, when comets approach the Sun, solar radiation and solar wind cause gas and dust to stream away, forming a bright, visible tail. However, new photos taken by the R Naves Observatory in Spain on November 5 showed that 3I/ATLAS had no such feature.

Despite expectations of intense outgassing, scientists observed that the object became five times brighter after its closest approach to the Sun (perihelion) and turned green, possibly due to diatomic carbon emissions. Interestingly, the object also displayed erratic movement, which could mean it is shedding material, yet still, no tail can be seen.

Some researchers believe that 3I/ATLAS might have a hardened or irradiated crust, which could alter how gases escape from its surface. Others, however, think something far more extraordinary could be happening.

Harvard astrophysicist Avi Loeb suggested that 3I/ATLAS might even be an alien spacecraft, citing its “unusual” motion and lack of a visible tail. Writing on Medium, Loeb explained that a normal comet should have shown a massive coma, a surrounding cloud of dust and gas, that would have been pushed away from the Sun to form a typical cometary tail. “No such tail is visible in the new images from November 5, 2025,” he wrote.

Earlier in July and August, 3I/ATLAS had displayed a rare sunward jet, known as an “anti-tail,” which was confirmed not to be an optical illusion.

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