Before You Call It an Alien Spaceship
Richard Jonathan O. Taduran, Ph.D. | 25 September 2025
On the first day of July 2025, a small telescope in Chile caught a faint streak of light hurtling in from the direction of Sagittarius. The object’s path was strange: its orbit was hyperbolic, meaning it was not bound to the Sun. Within hours, astronomers realized we were looking at the third confirmed visitor from another star system — a comet now catalogued as 3I/ATLAS (C/2025 N1).
Within days, social media had already crowned it an alien spaceship.
This is where the forensic scientist in me takes a deep breath. A comet discovery is not a crime scene, but the process of investigating one looks remarkably similar. Both require careful observation, disciplined reasoning, and a refusal to jump straight from “this is unusual” to “this must be extraordinary.” The frenzy over 3I/ATLAS is a reminder that a scientific mindset — evidence first, speculation later — is not just for laboratories. It belongs in our everyday lives.
The Rush to Aliens
3I/ATLAS is only the third interstellar object ever found, following ‘Oumuamua in 2017 and comet 2I/Borisov in 2019. Like those two, its orbit is clearly unbound, proving it came from outside the solar system. Astronomers expect it to reach perihelion — its closest point to the Sun — around the end of October 2025, and at no point will it come anywhere near Earth’s orbit.
Images from Gemini Observatory and the Hubble Space Telescope show a faint but definite coma, the fuzzy halo that forms when ices sublimate into gas. Spectra confirm ordinary cometary chemistry. Even its greenish hue is no mystery: it comes from diatomic carbon and cyanogen fluorescing in sunlight, a feature seen in many comets as they warm up.
Everything about 3I/ATLAS so far is perfectly consistent with a natural interstellar comet. Extraordinary, yes — but not extraterrestrial technology.
That hasn’t stopped some from suggesting otherwise. An arXiv essay by Harvard astrophysicist Avi Loeb and colleagues floated the possibility that 3I/ATLAS could be a probe, perhaps even a hostile one, and proposed a set of observational tests. The paper was not peer-reviewed, but it went viral. Headlines blared about “possible alien spacecraft,” memes circulated, and public imagination raced far ahead of the data.
I get the excitement. The idea that something built by another civilization might drift through our cosmic neighborhood is irresistible. But from a scientific and forensic standpoint, this is like declaring a cause of death before the autopsy is complete. It is the very thing we warn our students against: letting the hypothesis run ahead of the evidence.
Evolution and Evidence
As a biological anthropologist, I am keenly aware of how hard-won intelligence really is. On Earth, it took nearly four billion years of accidents, extinctions, and evolutionary bottlenecks before a primate capable of science, storytelling, and internet memes appeared. Intelligence is not inevitable — it is a rare, fragile outcome of countless evolutionary dice rolls.
That should remind us that the appearance of a technological artifact in our cosmic backyard is not the default expectation. It is a low-probability event that demands very high-quality evidence before we take it seriously.
The same disciplined reasoning applies in forensic science. We start with classification: is a stain human or animal blood? Are the marks shoeprints or tire tracks? Only once we know the class do we attempt individualization — whose shoe, whose blood. Astronomers are doing the same with 3I/ATLAS: first confirming if it behaves like a comet, which the evidence strongly supports, before considering other explanations.
Crucially, we build and test hypotheses systematically. Each observation — a brightness change, a trajectory shift, a new emission line — must be explained by the simplest natural mechanism that fits. Outgassing, dust fragmentation, and solar radiation pressure are tested first. “Alien propulsion” comes last, and only if every natural explanation fails.
This is not a failure of imagination — it is the discipline that makes science trustworthy. It keeps us from mistaking noise for signal and coincidence for intention.
The Scientific Discipline
Premature conclusions are not harmless. In criminal justice, they can lead to wrongful convictions. In science, they can erode public trust and turn every anomaly into a conspiracy theory. The temptation to go for the dramatic answer — to turn a comet into a craft — is strong, but the scientific mindset teaches us to slow down, shrink our error bars, and let evidence accumulate before we speak with confidence.
This discipline is more than an academic virtue — it is a civic one. The same cognitive shortcuts that make us see spaceships where there are none also fuel rumor-driven politics, moral panics, and mob justice. A society that forgets how to pause, investigate, and weigh evidence becomes dangerously easy to manipulate.
Perhaps what this interstellar visitor brings is not mystery, but a chance to practice thinking clearly under the night sky.