An interstellar object known as Comet 3I/ATLAS is currently undergoing a critical examination as it nears its closest point to the sun on October 29. This event, referred to as perihelion, is being closely monitored by prominent astronomer Avi Loeb from Harvard University, who describes it as an “acid test” that could reveal whether the object is a natural comet or a potential spacecraft of extraterrestrial origin.
First detected in July, Comet 3I/ATLAS is at a pivotal moment in its orbit. According to Loeb, if this object is indeed a spacecraft, it may take the opportunity during perihelion to alter its velocity. “The perihelion time for 3I/ATLAS was today at 11:47 UT (7:47 Eastern Time) according to the JPL Horizons fit to its trajectory. The uncertainty is only a few minutes,” he noted.
The upcoming perihelion presents a critical test under the sun”s intense heat and gravitational pull. Loeb explained, “If it is a natural comet glued together by weak forces, its heating by 770 watts per square meter may break it up into fragments, which would evaporate more rapidly due to their large surface area per unit mass.” He added that such an event could result in a significantly brighter cometary plume of gas and dust. Conversely, if 3I/ATLAS is technologically engineered, it could maneuver or release mini-probes, potentially displaying other technological signatures like artificial lights or excess heat from an engine.
Loeb”s hypothesis is supported by a unique assessment he developed, termed the “Loeb Scale,” which gauges the likelihood of an object”s artificial origin. He has assigned Comet 3I/ATLAS a score of 4 out of 10, suggesting that while it is most likely a natural comet, several anomalies elevate its status. “3I/ATLAS is most likely a comet of natural origin, but there are 8 anomalies that give it a rank of 4,” he stated.
Loeb has pointed out that the object is now moving away from the inner solar system towards Jupiter without any observable maneuvers towards Earth, which he finds intriguing. He remarked, “Based on its unlikely spacetime trajectory, 3I is a probe, in my opinion, but merely that.” He has expressed fascination with the unusual compositional data of the comet, noting that the gas plume is predominantly composed of carbon dioxide, carbon monoxide, and water, diverging from the typical water-ice-dominated makeup found in solar system comets. This distinctive composition raises speculation about its possible artificial origins, as it may indicate a byproduct from a propulsion system or industrial processes.
Loeb emphasized the importance of gathering data to better understand the nature of Comet 3I/ATLAS. “We have to collect as much data as possible to figure out its nature. The implication of alien technology would be huge and therefore we must take it seriously,” he asserted. He further compared the scale of the object to NASA“s largest rocket, stating, “Our biggest rocket, Starship, is a hundred times smaller than 3I/ATLAS, so in case it is technological—its sender possesses technological capabilities that are well beyond those that we possess.”
As the scientific community awaits further data from the flyby, it remains to be seen whether Comet 3I/ATLAS will reveal its true nature. Loeb concluded with a reminder of the limits of imagination in scientific discovery, stating, “Nature is more imaginative than the best script writers for science fiction movies in Hollywood. Rather than imagine who might be our dating partner, we better observe it.”
In the meantime, NASA has confirmed that Comet 3I/ATLAS poses no threat to Earth and will maintain a safe distance, noting that it is the third known object from beyond our solar system to pass through our celestial neighborhood. As it undergoes this critical “acid test,” the findings could reshape our understanding of the universe and the potential for advanced technological life beyond Earth.
