Interstellar comet 3I/ATLAS continues to baffle scientists with its strange acceleration. Credit: Wikipedia – International Gemini Observatory
The interstellar comet 3I/ATLAS has already been covered here. euro weekly newsis making headlines again, but this time it’s even stranger.
The new and unexpected change in its orbit has scientists scratching their heads, reigniting debate over whether what we’re witnessing is a completely natural cosmic event or something more mysterious.
A space wanderer who behaves strangely
New observations from the ALMA telescope array in Chile reveal that 3I/ATLAS is not exactly where physics says it is. In other words, it doesn’t follow the neat, predictable curve you’d expect from gravity alone.
Instead, it appears to be experiencing what experts call “non-gravitational acceleration.” This is a small but measurable force that throws it off its expected path, and is especially noticeable at its closest approach to the Sun.
Now, before you imagine the engines of an alien spaceship starting up, the simplest explanation is still a natural one. When a comet approaches the Sun, it releases gas and dust, creating a small thrust similar to a space jet.
But there’s a catch. If that’s what’s happening here, scientists should see a huge cloud of steam and debris around it. So far, nothing like that has appeared.
In the coming months, from November 2025 to January 2026, it will be closely monitored by telescopes including Hubble, James Webb, and the International Asteroid Warning Network. If this predicted cloud does not appear, things could get very interesting.
Mysterious echoes of the past: Remember ‘Oumuamua?
This is not the first time something like this has happened.
Back in 2017, the world’s first interstellar visitor, 1I/’ ‘Oumuamua, baffled scientists in exactly the same way. It also appeared to accelerate slightly with no visible signs of gas or dust. It’s the kind of behavior that has completely baffled experts.
Unlike normal comets, ‘Oumuamua had no visible tail or dust trail, and there was nothing to explain why it picked up speed. Some people jokingly call it a “dark comet,” but the idea of a comet without a tail is like a campfire without smoke.
Now, 3I/ATLAS appears to be following in its footsteps.
Its acceleration is estimated to be about 0.02 thousandths of a meter per second, suggesting that it somehow lost a huge amount of mass, perhaps about 5.5 billion tons of material, in a very short period of time.
But strangely, even the powerful James Webb telescope detected no such activity before October of this year, despite tracking a steady mass loss of about 150 kilograms per second.
Science is dichotomous: natural phenomenon or something else?
Not everyone agrees on what’s going on.
For some astronomers, 3I/ATLAS’ strange behavior is just one example of comet behavior that is still not fully understood. But others, including Harvard University astrophysicist Avi Loeb, think it may be time to at least consider other possibilities.
Loeb, who sparked controversy years ago by suggesting ‘Oumuamua may be of technological origin, says this new object deserves similar scrutiny.
“If we don’t see the predicted gas cloud by December, we need to consider the possibility of an artificial source of propulsion,” Loeb said.
The remark reignited a familiar debate, especially after British physicist Brian Cox flatly rejected the idea and argued that the behavior of objects is purely natural.
Loeb countered by pointing out that Cox had not published any scientific research on the object, although Cox himself had written more than a dozen peer-reviewed papers about its anomaly.
“For me, science is not defined by applause or TV charisma,” he says. “That’s determined by rigorous analysis of the data. And in this case, the data just doesn’t match our usual explanations.”
According to Loeb, the facts are simple but surprising. 3I/ATLAS is unusually bright, bluer than the Sun, and appears to have motion that cannot be explained by gravity alone.
Questions beyond science
So what exactly is driving 3I/ATLAS?
Are the ice and gas just reacting to sunlight in a way that we haven’t fully modeled? Or is it something strange, perhaps man-made in nature?
As of now, there are no answers yet. But one thing is for sure: this mysterious visitor from outside our solar system is forcing us to look at the universe with fresh eyes.
As Loeb said, the question is not whether 3I/ATLAS is a spacecraft. The real question is why is it moving as if it’s being pushed by something?
Perhaps the explanation will be completely mundane. But if we don’t, we may be witnessing something truly special: a quiet, almost imperceptible moment in history when we realize we may not be as alone as we think.
A small change in the arc of just a few seconds may one day change the way we view our place in the universe.
