Comet 3I/ATLAS Likely Intact — Scientists Reject Claims It Exploded or Is an Alien Probe

Comet 3I/ATLAS likely remains intact; experts urge caution over alien‑probe claims

Comet 3I/ATLAS — an interstellar visitor detected in July — most likely did not explode after reappearing from behind the Sun, according to multiple astronomers who have reviewed recent observations. Headlines and blog posts suggesting the object fragmented or might be an artificial spacecraft have attracted attention, but the majority of the scientific community regards the comet as a natural object showing ordinary cometary activity.

What sparked the controversy

On Nov. 9 amateur astronomers Michael Buechner and Frank Niebling captured images showing bright jets of material streaming from 3I/ATLAS. A Nov. 10 write-up on Futurism cited a blog post by Harvard astrophysicist Avi Loeb, who interpreted those images to estimate a large loss of mass and argued the object’s behaviour was difficult to reconcile with a typical comet.

"If forthcoming observations show an intact nucleus, then non‑natural explanations should be considered," Loeb wrote, using his calculated mass loss to argue the comet would need to break into many pieces if it were purely natural.

Why most astronomers disagree

Researchers who study comets say the observations instead point to normal cometary activity — jets, a coma and increased brightness as ices sublimate near the Sun. Qicheng Zhang, a postdoctoral fellow at Lowell Observatory, told Live Science that the images look like a "fairly ordinary/healthy‑looking comet" and that he sees "no sign at all that the nucleus broke apart."

Penn State astronomer Jason T. Wright has also publicly dissected Loeb's claims, listing several methodological problems and arguing that Loeb misinterpreted orbital measurements and mass‑loss estimates. Wright and others say the claimed anomalies stem from incorrect assumptions rather than clear evidence of artificial origin.

What we know about 3I/ATLAS

• 3I/ATLAS briefly passed behind the Sun and reached perihelion (closest approach to the Sun) on Oct. 29, when increased heating can drive sublimation and bright jets.
• Solar radiation makes jets, coma and tails more conspicuous, so amateur and professional observers can often see dramatic activity without a nucleus fragmenting.
• The object is an interstellar visitor — only the third such comet recorded — and appears to be unusually massive compared with previous interstellar objects. It may also be extremely old, perhaps billions of years.

Visibility and what to expect next

From Earth, 3I/ATLAS is rising higher above the eastern horizon and is observable through modest telescopes (about a 6‑inch aperture) in much of the Northern Hemisphere when skies are clear. The comet will make its closest approach to Earth on Dec. 19, which should produce more observations and better data to clarify its nature.

Until then, astronomers urge caution: extraordinary claims require extraordinary evidence. Current peer commentary favors a natural comet undergoing ordinary mass loss and jet activity rather than an exploded nucleus or engineered probe.

Bottom line

While some high‑profile speculation suggested 3I/ATLAS might have fragmented or be artificial, the prevailing expert view is that it remains a natural and intact comet. Continued observations through December will help settle remaining questions.