The interstellar object known as 3I/ATLAS has captivated astronomers since its discovery, and recent events suggest it may have undergone a dramatic transformation near the Sun. Harvard astrophysicist Avi Loeb, a prominent figure in the study of interstellar objects, has proposed that 3I/ATLAS could have exploded or fragmented during its perihelion – the closest point to the Sun – leading to spectacular “fireworks” in the form of massive jets and trails. This hypothesis stems from observations showing the object shedding mass at an unprecedented rate, far exceeding typical cometary behavior.
As 3I/ATLAS emerged from behind the Sun after its perihelion in late October 2025, images captured by British astronomers Michael Buechner and Frank Niebling revealed an enormous “anti-tail” extending about 620,000 miles toward the Sun and a “smoking” trail stretching 1,860,000 miles in the opposite direction. Loeb’s calculations indicate that to produce such jets, the object would need to have absorbed solar energy over an area larger than 617 square miles, equivalent to a sphere roughly 14.3 miles in diameter – four times his earlier estimate of at least 3.1 miles across and a mass of 33 billion tons.
The mass loss rate escalated dramatically: from around 330 pounds per second in early August 2025, based on James Webb Space Telescope data, to an astonishing 4.4 million pounds per second near perihelion. This surge, Loeb argues, implies the object may have broken into at least 16 fragments, increasing its surface area and accelerating sublimation of ices like carbon dioxide and water. “Was the dramatic mass loss and brightening of 3I/ATLAS at perihelion evidence that it disintegrated?” Loeb questioned in his blog, suggesting the alternative that it might not be a natural comet at all if it survives intact.
Media outlets have amplified the intrigue surrounding 3I/ATLAS in the days following Loeb’s analysis. Reports indicate the object has been observed without its characteristic comet tail after its solar encounter, reigniting debates about its composition and origin. This tail loss, spotted in recent images, suggests it may not behave like a typical comet, with some scientists noting its size as “very anomalous.”
Further observations reveal signs of “non-gravitational acceleration,” a deviation from expected orbital paths that could indicate outgassing or other forces at play. One analysis points to evidence of “galactic cosmic ray” processing on the object’s surface, which might imply a long journey through interstellar space but raises concerns about its stability and potential hazards. Loeb has even warned that fragments from 3I/ATLAS could pose risks, potentially delivering “unwanted gifts” to Earth, though critics note its trajectory does not directly intersect our orbit.
Loeb, known for bold theories, hasn’t shied away from extraterrestrial possibilities. He notes that the jets could be explained by technological thrusters, which require far less mass loss than natural sublimation – chemical rockets achieve exhaust speeds 10 times higher than cometary outflows. Advanced alien propulsion might reduce fuel needs even further, making 3I/ATLAS a candidate for an artificial probe. Its trajectory, aligned closely with the solar system’s planets and inclined by just 5 degrees to the ecliptic plane, adds to the anomaly.
Astronomers eagerly await clearer views as 3I/ATLAS approaches Earth on December 19, 2025, and Jupiter in March 2026. Whether it emerges as a fragmented cloud or a resilient single body will test Loeb’s hypotheses. NASA has faced criticism for withholding some images, but upcoming data from telescopes like Hubble and Webb could resolve the debate.
As the third confirmed interstellar object after ’Oumuamua and 2I/Borisov, 3I/ATLAS underscores the mysteries of our cosmic neighborhood. If it did explode, the remnants could offer invaluable insights into interstellar materials – or, as Loeb speculates, hints of advanced technology from beyond our solar system.
