On October 29, the unique interstellar object 3I/ATLAS, discovered just four months ago, approached the Sun. Not only scientists, but also ordinary people are closely monitoring what is happening to him. At the instigation of Harvard astrophysicist Avi Loeb, 3I/ATLAS has long been dubbed an alien spacecraft by the press. Loeb suspects that the object is of artificial origin and may be preparing for brake operations and the launch of a reconnaissance probe.

Astrophysicist Avi Loeb believes the 3I/ATLAS object is preparing for a gravitational run before approaching Earth

Discovered on July 1 by NASA's telescope network, 3I/ATLAS entered the solar system several months ago and reached its closest point to the Sun on October 29. Most experts consider it an interstellar comet, however, according to Avi Loeb, it cannot be ruled out that it is of artificial origin.

Loeb was previously chairman of the astronomy department at Harvard University. He currently directs the Galileo Project and serves as director of the Black Hole Initiative at Harvard University and the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics.

Although his reputation in the scientific community was somewhat tarnished by his fondness for sensational speeches in the press, he continued to actively publish and was much more restrained in his scientific articles than in his comments in the Daily Mail.

Loeb believes that 3I/ATLAS has many unusual features that set it apart from other comets. And now the time has come to be able to confirm or refute this. The subject is in the ideal zone so that braking or other actions can reveal its true nature.

According to Loeb, if his suspicions are correct and 3I/ATLAS is indeed an alien ship, it could use the sun's gravity to slow down before approaching Earth. In addition, the astrophysicist believes that, hidden behind the Sun, 3I/ATLAS could launch miniature reconnaissance probes.

The latest observations, according to Loeb, indicate that 3I/ATLAS started the engine to brake

3I/ATLAS has not been visible from Earth for several days, but the solar observing spacecraft continues to monitor its activities. American astronomers Qichen Zhang and Carl Bettams, who analyzed the latest data on the object, noticed a rapid increase in 3I/ATLAS's brightness.

In addition to the changed brightness, another unusual phenomenon was observed: the light emitted from it changed from the red to the blue part of the spectrum. Avi Loeb believes that in the natural course of events, such coloration would not be possible. The authors of the work themselves admit that they cannot explain what is happening.

In an article on Medium, Loeb analysis observations by astronomers. He noted that 3I/ATLAS is glowing much faster than the Oort cloud comet approaching the Sun, and that the color change detected by the sensors could indicate that the object's temperature has exceeded that of the Sun.

If we consider 3I/ATLAS as an artificial device, the sharp increase in brightness and temperature increase is easy to explain. The astronomers' instruments simply noticed its engines were on.

Avi Loeb stated that the probability of such an object existing is one in ten million million.

According to Loeb, chances are there's nothing to worry about and the object is actually a comet. On a hypothetical scale where zero is a natural object and 10 is definitely a man-made device, Loeb would give 3I/ATLAS a four. For a simple comet, he said, this object has too many strange features. At the same time, there is no reliable evidence of its artificial origin.

The astrophysicist counted nine anomalous properties of the object. First, its orbit is aligned within 5 degrees of the ecliptic plane of the planets around the Sun. Second, in July and August 2025, 3I/ATLAS developed an antitail—a beam of particles pointed toward the Sun. This is not unusual for comets and is often explained by an optical illusion that occurs due to a change in their position relative to Earth. However, Loeb believes that in the case of 3I/ATLAS, the flow of matter has actually changed direction.

The counter-tail fits perfectly with his spacecraft hypothesis: a beam of particles pointed toward the Sun could be the braking thrust of an alien vehicle's engine.

The third anomalous feature of 3I/ATLAS, according to Loeb, is that, despite its enormous size, the object is moving significantly faster than expected. Additionally, its orbit passes at a short distance from the three planets of the solar system. Furthermore, at perihelion, the object cannot be observed from Earth. Such coincidences happen very rarely.

Some oddities are related to the chemical composition of 3I/ATLAS. As it turns out, its air stream contains significantly more nickel than iron and very little water – just 4%. In regular comets, water is the main component.

Ultimately, Loeb felt suspicious that 3I/ATLAS came from the same direction that was said to be the source of the “Wow!” famous. radio signal. In 1977, it was recorded by a radio telescope listening to the sky as part of the SETI project to search for extraterrestrial civilizations. The transmission has properties that suggest its artificial and supernatural origin (however, this cannot be proven).

According to Loeb's calculations, the chance of all these anomalies appearing at the same time is one in ten million million. In other words, this simply does not happen.

A few years ago, Papua New Guinea authorities accused Avi Loeb of stealing a crashed alien plane.

Most experts do not share Loeb's enthusiasm. He himself occasionally urged against jumping to conclusions and emphasized that a natural origin for 3I/ATLAS is still more likely than an artificial one. However, in his opinion, caution is necessary.

The search for theoretical features that could distinguish objects of man-made origin had been part of Loeb's scientific interests from the beginning. In 2012, he proposed searching for traces of alien megacities on exoplanets, and in 2017 he published a paper in which it was suggested that mysterious fast radio bursts could be the result of the activity of extraterrestrial civilizations.

In 2018, Loeb, then head of the Department of Astronomy at Harvard University, turned his attention to Oumuamua, the first interstellar object discovered by humans. Oumuamua is a cigar-shaped asteroid: 400 meters long and just 30 meters in diameter. At that time, Loeb also tended to believe that we were facing an alien machine. Because this object soon left the solar system, this cannot be proven or disproved.

Perhaps the most ridiculous story of Loeb's career involves his interest in the IM1 meteorite that fell to Earth in 2014. Loeb was intrigued by IM1's unusually high speed. He suggested that such an object could appear outside the solar system. This leads to the inevitable conclusion: IM1 also has an artificial origin.

Astrophysicists analyzed seismic records and concluded that IM1 exploded in the Papua New Guinea region. Strange spheres containing iron, magnesium and titanium have actually been found on the ocean floor at the site where the debris is believed to have fallen.

An unusual side effect of Loeb's research was a conflict with the island's authorities, who accused him of stealing fragments of an alien ship.

When experts got down to business, the theory of IM1's alien origin immediately collapsed. Seismologist Benjamin Fernando reanalyzed the seismic activity data that underpinned Loeb's conclusions and discovered that what he found was in no way a trace of a meteorite explosion. In fact, seismometers recorded vibrations caused by trucks passing by the lab.