Astronomers have detected rhythmic “heartbeat” pulses from interstellar object 3I/ATLAS as it approaches Earth, with jets of gas and dust erupting every 16.16 hours and causing its brightness to vary by up to 40 percent.
NASA and the European Space Agency classified the object as a lifeless comet, explaining the pulses as a result of surface ice heating and venting as the nucleus spins under the Sun’s warmth.
Harvard astrophysicist Avi Loeb has questioned the explanation, arguing the strong brightness changes are unusual because most visible light comes from the surrounding coma, not the nucleus. He noted several unexplained anomalies but acknowledged the scientific consensus that the object is natural.
NASA said 3I/ATLAS poses no threat and will pass about 170 million miles from Earth on December 19, offering researchers a chance to refine planetary monitoring efforts.