Oumuamua appeared in 2017, without exhibiting the normal characteristics of a comet. It lacked a coma, dust or tail, looking like a giant cigar-shaped piece of rock floating in space. Borisov came into the scene two years later with all the features of a conventional comet. On 1st, July 2025, the interstellar trinity was completed when 3I/ATLAS tore into our solar system at a speed of 209,000 kilometers, making it the fastest of the trio. However, recent discoveries have led space experts to speculate wildly on the origins of the comet, with news of alien involvement afoot.

ATLAS (Asteroid Terrestrial-impact Last Alert System), a NASA-funded survey telescope in Rio Hurtado, Chile, was the first to report their observations of comet 3I/ATLAS on July 1, 2025. These observations were also corroborated by three other ATLAS telescopes on the planets. The comet was named after the ATLAS survey team, with the “I” standing for “interstellar”, and the “3” in its name saying the it is the third known interstellar object.

After the initial discovery of the comet, gears began to turn as space research companies began to wildly collect data. Unlike comets bound to the sun’s gravity, 3I/ATLAS is traveling on a hyperbolic orbit that will see it leave the solar system and travel again into interstellar space. This means there will be no return trip for the comet. Hence, the reason astronomers are scrambling to collect all the data they can get before the this comet formed by the components of another star system gets to the exit door of this solar system.

NASA’s Hubble Space Telescope previously got a look at the comet in July, collecting data that allowed astronomers to peg the size of the comet’s solid, icy nucleus between 1,000 feet and 3.5 miles wide. The James Webb Space Telescope then observed the interstellar object on August 6 in near-infrared light, followed by the newer SPHEREx telescope from Aug. 7-Aug. 15, to get a better idea of its physical properties and chemical makeup.

3I/ATLAS is expected to pass through the planet Mars on Friday, 3rd October, 2025. Researchers have anticipated this trajectory and have made ample preparations to collect data as the comet comes within 18,600 miles of Mars. Two Mars orbiters, Mars Express and ExoMars Trace Gas Orbiter, will be able to observe 3I/ATLAS until 7th of October. Then between 2nd and 25th of November, ESA’s Jupiter Icy Moons Explorer (Juice) will observe the comet with its instruments when the object is expected to be in a “very active state” following its closest approach to the sun.

Wild Theories?

Due to its peculiarities, 3I/ATLAS has been at the center of several wild theories, with alien involvement being the core of such discussions. Avi Loeb, professor of science at Harvard, has been the loudest proponent of the alien story.

In an interview with Newsmax’s “Wake Up America”, he posted that there were some anomalies about the comet, suggesting that there was a chance it could be alien technology. One of such anomalies Loeb pointed out was the size of the comet, which according to him was “at least five kilometers in diameter, but it could be up to a factor of 10 bigger than that. And the puzzle here is that it’s at least a thousand times more massive than the previous object, Borisov, which was a comet.”

“But then you ask yourself: How come the previous object was roughly a couple of times the size of a football field, and this one is of … Manhattan Island? There is also not enough rocky material in interstellar space to accommodate the delivery of a size roughly the size of a Manhattan Island once per decade. Now, in addition to that, its trajectory is aligned with the planet’s to within five degrees, and the chance of that happening at random is 1 in 500. So here is another anomaly. In addition, there was scattered light in front of the object 10 times longer than it is wide in the Hubble Space Telescope image. Usually, we see scattered light behind the object away from the sun, because dust particles are pushed away by radiation pressure from the sun.” Loeb added.

He believes these factors are reason enough for the world to keep its eyes on the object and study it while it is within range.

This will not be the first time Loeb has pinned the “alien technology” tag on extraterrestrial objects. In 2018, Loeb co-authored a study in The Astrophysical Journal Letters, investigating the potential origins of the Oumuamua in which the possibility that it is “of an artificial origin” was seriously considered.

Trajectory of the interstellar comet in the solar system. It will be visible on Earth on December 19. It has recently been reported that it survived a recent solar storm.

Loeb and his colleague wrote that ‘Oumuamua could possibly be something called a lightsail, the technology that uses light from the sun or other stars to push it through space.