NASA Issues Final Verdict on 3I/ATLAS Comet Following Alien Spaceship Theories — What Is The Truth?

For those peering nervously at the night sky, fearing that our newest celestial visitor might be the vanguard of an extraterrestrial fleet, the scientific community has a message: you can officially breathe a sigh of relief. The mysterious object that has dominated headlines and stoked the fires of internet conspiracy theories for months is, as experts have long suspected, a traveller of the natural variety. Confirmed to have been discovered on July 1, 2025 by the ATLAS survey telescope in Chile, the object was designated 3I/ATLAS as it represents the third-ever interstellar visitor found in our solar system.

Even though the idea of an interstellar 'scout' ship is exciting for movies, a group of dedicated astronomers has just found the strongest proof yet that 3I/ATLAS is a comet and not a ship. The interstellar visitor, which first crossed our cosmic borders in July 2025, has been closely watched, but new research has effectively put another nail in the coffin of the 'alien technology' story.

The James Webb Space Telescope (JWST) recently did some chemical tests and found that the ratio of carbon dioxide to water ice is higher than normal for local comets. It also found gas that is unusually rich in nickel, which suggests that it formed in a planetary system that is much older than ours.

Silence From the Stars

The latest breakthrough comes from a team associated with Breakthrough Listen, an international group tasked with the unenviable job of hunting for intelligent life across the vastness of space. As 3I/ATLAS made its closest approach to Earth on Dec. 19, 2025, the team trained the massive Green Bank Telescope in West Virginia directly at the object.

They weren't looking for ice or dust; they were listening for the tell-tale hum of machinery. The search covered frequencies between 1 and 12 GHz, boasting enough sensitivity to detect a transmitter with the power of a standard mobile phone at that staggering distance.

In the world of SETI (Search for Extraterrestrial Intelligence), these are known as technosignatures — radio frequencies or signals that could only originate from an artificial source. The results were telling: there was nothing. No pings, no transmissions, and no sign of a propulsion system.

The silence from the comet was absolute, suggesting it is exactly what it appears to be — a relic of a distant star system. Conversely, the MeerKAT telescope did detect signatures of hydroxyl, a natural chemical byproduct created as sunlight breaks down the comet's water ice.

Despite the lack of radio chatter, some remain unconvinced. Harvard astrophysicist Avi Loeb, known for his provocative theories regarding the interstellar object 'Oumuamua, has maintained a healthy level of scepticism. While Loeb conceded on Medium that the object is 'most likely a comet of natural origin,' he has criticised the brevity of recent observations.

Loeb argued in January that a truly 'proper observing program' would require monitoring the object from multiple directions over a much longer period before ruling out artificiality entirely. Loeb has even suggested that the nucleus could be as large as 15 kilometres in diameter based on early 'plateau' brightening data, a figure far exceeding NASA's more conservative estimates.

Tracking the Interstellar Journey of 3I/ATLAS Through Our System

3I/ATLAS is an amazing find, even without the alien interest. It is the third object ever confirmed to have come from outside of our solar system. NASA first noticed the visitor going at an incredible 137,000 mph.

This amazing speed, along with its path, proved that it was born in a star system far away and then violently thrown into the empty space between stars. Its path is a hyperbolic trajectory, which means that the sun's gravity doesn't hold it down, and it will eventually leave our system and drift forever between stars.

The numbers show that this icy traveler may have been wandering through the dark for billions of years, starting its journey from the general direction of the constellation Sagittarius. It came within 170 million miles of Earth, which is about twice the distance from Earth to the sun, and this was a rare chance to study it.

Using data from the Hubble Space Telescope, astronomers have estimated the size of its solid, icy nucleus to be anywhere from 1,400 feet to 3.5 miles in diameter. The comet made its closest approach to the sun (perihelion) on Oct. 29, 2025 at a distance of about 1.36 AU, just outside the orbit of Mars.

NASA authorities have been working overtime to keep the public's imagination from running wild. Even reality TV icon Kim Kardashian weighed in on the mystery in October 2025, prompting a direct response from then-Acting Administrator Sean Duffy, who assured her: 'No aliens. No threat to life here on Earth'. Nicola Fox of NASA's Science Mission Directorate echoed this sentiment, stating firmly that no evidence exists to suggest the object is anything other than a fascinating, albeit natural, comet.

3I/ATLAS is already on its way back into the interstellar depths as it follows its hyperbolic orbit. It is currently heading away from us, but it is expected to be visible through telescopes until the spring of 2026, when it will pass the orbit of Jupiter.

For now, we have a lot of pictures that NASA released in November and the knowledge that the universe still has a lot of secrets to tell us, even if we are alone in this one. NASA's Eyes on the Solar System interactive simulation lets space fans keep track of its last exit.