3I/ATLAS was first spotted on July 01, 2025 by the Asteroid Terrestrial-impact Last Alert System (ATLAS). The third-ever interstellar visitor recorded since 1I/Oumuamua (2017) and 2I/Borisov (2019) has left everyone baffled. The behavior of the comet ever since its discovery has defied the textbook definition of a comet.
Having said that, the burning question is who gets to decide if the object is indeed a comet and not have any extraterrestrial technological origin? The scientific community at large has been very dismissive over the conjecture and wouldn’t even give heed to its possibility. However, not all are bound with the traditional explanation of the world rooted in past studies when we know so terrifyingly little about the cosmos. Professor Avi Loeb, a Harvard astrophysicist who enlisted at least 13 anomalies on 3I/ATLAS has been subject of much ridicule for his hypothesis backed by 11 papers on the interstellar interloper.
In his latest blog, Loeb slams the experts and NASA officials for ignoring the anti-tail properties of 3I/ATLAS that throw the convention out of the window. He remarks
Why are comet experts and NASA officials so reluctant in displaying curiosity about the anti-tail or other anomalies of 3I/ATLAS?
So what exactly is the anti-tail anomaly of 3I/ATLAS? Loeb explains
The orientation of the anti-tail flipped relative to the direction of motion at perihelion and is definitely not a matter of perspective, as is the case for some comets. Micrometer-scale, refractory dust particles would have been swept away from the Sun by the solar radiation and wind. The anti-tail must therefore contain something else.
Loeb gave links to three academic papers he wrote explaining his hypothesis further. In one of the papers, he writes,
I consider an alternative interpretation of the anti-tail, associating it with scattering by a swarm of macroscopic non-volatile objects that are not affected by the solar radiation pressure or the solar wind. This alternative model is motivated by the latest post-perihelion data on 3I/ATLAS
We wrap with Avi Loeb’s opening remark of his latest blog
There is no doubt that we can learn something new from the interstellar object 3I/ATLAS, irrespective of whether it is an icy rock or a spacecraft. The only obstacle to learning is comet experts who display the arrogance of expertise.
See Also: 3I/ATLAS: Japan’s XRISM Probe Captures X-ray Emission From Exocomet Ahead Of Earth Flyby