The Moon attracts all eyes. While the next missions Artemis prepare its industrialization, some researchers suggest another path to explore in parallel. What if extraterrestrial civilizations had already surveyed our Solar System, without ever coming into direct contact? What if autonomous and intelligent machines, capable of reproducing on their own, had left traces on our satellite? The idea, far from being fanciful, is based on coherent models and a central argument. The Moon could well be the key to a billion-year-old enigma.
When science imagines machines capable of reproducing
In 1966, the posthumous work of John von Neumann laid the foundations for the concept of a universal machine capable of reproducing itself. Since then, this idea has migrated from theoretical spheres to the concrete discussions of scientists engaged in the search for extraterrestrial intelligence. The principle is simple. An advanced civilization could delegate galactic exploration to machines programmed to self-replicate, using the resources they find there to build their replicas and explore even further.
Professor Alex Ellery, director of the Center for Self-Replication Research (CESER) at Carleton University, believes that these probes represent a plausible, logical and efficient strategy for traveling the Milky Way. He says they offer a way to maximize knowledge collection without the biological constraints of space travel. These machines do not need oxygen or food, and can survive accelerations much greater than those supported by a living being.
These probes, by reproducing themselves from the materials available in each system visited, could colonize the entire galaxy in just a few million years. This scenario echoes the Fermi paradox. If such technologies are possible, why haven't we detected anything? Maybe because we're looking in the wrong place. Or in the wrong way.
Self-replicating probes hidden in our Solar System?
Rather than looking for radio signals from distant stars, as the SETI program traditionally does, Ellery suggests looking to our own space environment. It suggests that self-replicating probes may have already reached our Solar System, and that some are still operating there discreetly. The trick would then be to spot the technological signatures they leave in their wake.
According to Universe Today, such a probe would follow a predictable exploration pattern. It would start by identifying metal-rich asteroids, then establish bases in strategic locations, such as the surface of a rocky moon. It would reproduce there, manufacture other specialized devices (scouts, sentinels or builders) and launch the exploration of the target system in an exhaustive manner. Some models even include the possibility of seeding life, through directed panspermia.
At each stage, technosignatures may remain visible. This includes artificial structures or isotopes distributed in unusual ways. We can also detect certain minerals that are impossible to justify solely by geology. You still need to know where to concentrate your efforts. Indeed, the immensity of the Solar System makes any research extremely complex. It therefore seems preferable to start with the areas already explored.
The Moon, a field of inquiry for the next generation
Among all the accessible celestial bodies, the Moon seems the best candidate for harboring traces of such activity. It is geologically stable, relatively close, with no atmosphere or tectonics to erase the evidence. According to Ellery, a self-replicating probe could have set up a manufacturing base there using lunar materials. Magnox-type nuclear reactors, using local resources such as thorium and neodymium, could have operated there and left isotopic signatures still detectable today.
The author even mentions a bold hypothesis. That of an artifact voluntarily left by a probe in exchange for the resources exploited, a “gift” accessible only to a sufficiently advanced civilization. A universal manufacturer, for example, capable of propelling humanity into a new technological era.
If the theory remains speculative, it gains credibility as our presence in space strengthens. Future lunar missions, whether scientific or commercial, could incorporate technosignature detection protocols. The search for extraterrestrial intelligence would no longer be limited to the starry sky, but would be anchored in the gray dust of our closest neighbor. Because before looking for civilizations in the distance, it might be time to examine the stones we tread on.
With an unwavering passion for local news, Christopher leads our editorial team with integrity and dedication. With over 20 years’ experience, he is the backbone of Wouldsayso, ensuring that we stay true to our mission to inform.
