Why Harvard astronomer Avi Loeb thinks 3I/ATLAS is defying comet physics

A caller acceptable of deep-space images has reignited 1 of the strangest technological arguments of 2025. The photos amusement sideways jet-like lines shooting retired from the interstellar entity 3I/ATLAS.

Their geometry is truthful antithetic that Harvard astrophysicist Avi Loeb says they whitethorn not beryllium earthy astatine all.Some astronomers importune the entity is simply a weird comet. Others judge Loeb is erstwhile again over-interpreting anomalies. But Loeb says the caller information cannot beryllium ignored: the lines look similar the paths of smaller ejected objects travelling alongside 3I/ATLAS.

Here’s what the statement is truly about.

What precisely has been discovered?A caller stacked representation taken connected 20 November shows 2 thin, ruler-straight lines extending astir 1 cardinal kilometres connected either broadside of 3I/ATLAS.

Unlike a mean comet tail, these lines tally perpendicular to the Sun–object axis, forming an X with the accustomed process and anti-tail.The problem: comets bash not usually nutrient specified sideways features. Their jets thin to constituent distant from the Sun due to the fact that star radiation pushes particulate and state successful predictable directions.

Loeb’s statement is simple:

If these lines are existent and not outer streaks, they look similar the trails of smaller objects that peeled distant from 3I/ATLAS adjacent perihelion.

Why the lines don’t behave similar earthy jets

Loeb highlights 2 anomalies:

1. Perfect straightness

3I/ATLAS rotates astir each 16 hours. Any earthy pitchy should person produced disposable wiggles oregon breached patterns from that rotation. Instead, the lines are perfectly constrictive and consecutive implicit hundreds of thousands of kilometres.

2. Wrong orientation

Jets caused by sunlight and particulate unit look on the Sun-facing side. These lines beryllium astatine close angles to that axis, which is highly hard to explicate with modular comet physics.To lucifer the observed distance, the smaller objects would request speeds of astir 500 metres per second, which Loeb notes is compatible with tiny fragments separating — whether people oregon artificially.So… could this beryllium alien technology?

Loeb does not assertion the features are artificial. He offers a fork:

This isn’t the archetypal clip Loeb has taken specified a stance. His enactment connected ‘Oumuamua and the Galileo Project has made him the astir salient fig successful the “open-minded but data-driven” camp.

At Harvard helium remains a divisive but influential dependable pushing astronomy to dainty anomalies seriously.

Why this matters

3I/ATLAS is lone the 3rd confirmed interstellar entity ever observed. Every information constituent offers uncommon penetration into materials, structures and behaviours shaped extracurricular the Solar System.The caller features besides onshore successful the mediate of a polarised technological environment. Loeb’s critics accidental helium raises alien-technology hypotheses excessively freely.

His supporters reason that organization astronomy is excessively speedy to disregard the unexplained.But the images are public, the measurements are clear, and the sideways lines are not casual to hand-wave away. Whether earthy fragments oregon technological artefacts, the improvement demands explanation.And if the features crook retired to beryllium outer streaks, arsenic immoderate sceptics hope, the treatment volition inactive person revealed however subject reacts to anomalies successful existent clip — with caution, disagreement and curiosity rubbing uncomfortably against 1 another.What happens next?Astronomers volition proceed tracking some the main entity and the faint lines to spot if the suspected mini-objects:

If the lines stay unchangeable and the objects persist, Loeb’s lawsuit becomes stronger. If not, the comet proposal wins.Either way, this is shaping up to beryllium 1 of the defining astronomical debates of the year.