3I/ATLAS Just Did Something Impossible Near Mars

 

A One-of-a-Kind Guest

Occasionally, the solar system hosts a cosmic visitor—an interstellar object that just happens to be flying by from outside our Sun's home turf. The most recent guest, 3I/ATLAS, recently amazed astronomers by doing something no one believed was possible: a dramatic flyby close to Mars that defied expectations about what interstellar bodies should do.

This is just the third interstellar object ever discovered, following the legendary 'Oumuamua in 2017 and comet Borisov in 2019. Unlike typical comets and asteroids, these objects are not gravitationally tied to the Sun—these are tourists from other star systems, zooming by at breakneck velocities.

What Happened Near Mars

As 3I/ATLAS plunged into the inner solar system, astronomers followed it with great interest. Everybody predicted an uneventful passage: a faint trail in the sky, which would grow dimmer and move on. But as it neared Mars, something quite remarkable occurred.

Rather than passing by, 3I/ATLAS unexpectedly glowed much brighter and emitted a bizarre outburst of material, much stronger than predicted for a small, icy visitor. More inexplicably, it seemed to change its course ever so slightly for a brief time, as though an intangible force pulled on it.

Why It's "Impossible"

Interstellar objects generally travel so quickly and follow such exact hyperbolic trajectories that the gravity of planets has nearly no detectable influence on them. But with 3I/ATLAS, scientists observed what appeared to be a faint gravitational boost—or maybe an outgassing effect—close to Mars that affected its motion in a manner that existing models did not predict.

Adding to the intrigue, the makeup of material released by 3I/ATLAS isn't what astronomers typically observe from comets within our solar system. Some believe it may have exotic ices or products that are created under extraterrestrial stellar conditions, while others are hoping it may be an indicator of how planets are formed in other systems.

Why This Matters

3I/ATLAS provides scientists with an invaluable opportunity to investigate raw material from another star system—a chemistry and physics time capsule from regions we are not yet capable of accessing. If its bizarre activity close to Mars is true, it will potentially compel scientists to revise their understanding of interstellar objects' behaviors in the solar system bodies, and even perhaps the behavior of gravity and outgassing at extreme environments.

Looking Ahead

Astronomers across the globe are competing to collect data before 3I/ATLAS vanishes into the unknown once and for all. Already, Earth-bound telescopes and orbiting observatories are monitoring its dwindling tail and enigmatic chemical signals.

Whether the Mars anomaly was an accident, an unusual chemical reaction, or even something entirely more bizarre, one fact is certain: 3I/ATLAS has just re-written the rulebook on interstellar visitors.