Authors' Introduction
- Could extraterrestrial technology be lurking in our backyard – on the Moon, Mars or in the asteroid belt? We think it’s worth a look.
- The idea that a planet like Mars might host cities and technology gained traction in scientific circles when Percival Lowell popularised his theory of ‘canals’ on Mars between 1894 and 1908. He claimed that these were artificial irrigation channels built by Martians to transport water from the poles to equatorial cities. Not all astronomers agreed with Lowell, but the possibility of an inhabited Mars couldn’t be immediately dismissed. The excitement generated by his hypothesis inspired works of science fiction like H G Wells’s War of the Worlds (1898), in which Martian invaders come to colonise Earth and exploit its resources. It also fuelled a growing public belief that we might not be too far from another population of advanced extraterrestrial beings.
- What would it mean to find alien technology close to Earth? The implications would be shocking and transformative. Such a discovery would instantly upend humanity’s sense of itself in the hierarchy of the cosmos, suggesting that we are not alone, but that visitors have, in fact, been here before. The difference between an extraterrestrial civilisation light years away and one that has touched down or hovered so close to home could be the difference between unproven theory and documented reality. In a Universe where distances render most forms of contact nearly impossible, proximity changes everything.
- Lowell’s hypothesis about canals on Mars did not last, of course. By the 1930s, improved instruments revealed that the ‘canals’ were optical illusions. And by the 1960s, scientific evidence had shut the door on the idea of alien civilisations within the solar system. Venus was too hot. Mars was barren. Science fiction turned to the stars – and, with the discovery of exoplanets (Earth-like worlds that could be habitable), so did science.
- Yet we can’t rule out the possibility that aliens have paid a visit, or that alien technology is already here. After all, our own space-exploration activities have included missions on trajectories beyond the boundaries of the solar system. The Voyager 1 and Voyager 2 spacecraft, launched by NASA in 1977, have already exited the solar system, while other spacecraft such as Pioneer 10, Pioneer 11 and New Horizons are all on course to reach interstellar space. Studies are currently underway by the Breakthrough Starshot project to develop a tiny ‘nanocraft’ that would be propelled with a laser toward the nearby Alpha Centauri star system at a fraction of the speed of light. These examples illustrate the possibility that human technology is at least conceptually capable of sending spacecraft to nearby planetary systems. And if this is something within our reach, then isn’t it possible that an extraterrestrial civilisation (if it exists) would also be capable of such a technological feat?
Authors' Conclusion
- The barriers to searching for technosignatures within our solar system are not technological – they’re cultural. While interest in life elsewhere in the Universe has surged, the idea of nearby technosignatures has lagged behind, often dismissed or overshadowed by speculation rooted in science fiction and pseudoscience. This vacuum, filled by fringe narratives, has made scientists wary of engaging with the topic for fear of damaging their reputations. The notion that a local technosignature could pose a security threat adds to the reluctance. Cultural stigma continues to discourage researchers from even low-risk efforts, such as examining existing planetary data for unexplained anomalies. When these pressures ripple through the scientific community, they can create an informal but powerful taboo – one that sidelines legitimate lines of investigation.
- This isn’t how science should work. The search for technosignatures is grounded in a simple truth: technology has emerged at least once – here on Earth. Beyond that, the possibilities are wide open. We shouldn’t limit ourselves to searches of planets light years away when extraterrestrial technology might exist within our own solar system. To explore this seriously, we need to prioritise data collection and accessibility, enabling interdisciplinary teams – engineers, scientists and data analysts – to investigate potential signals, rule out false positives, and establish clear criteria for distinguishing genuine anomalies from noise. Scientists must be willing to take intellectual risks: to mine existing datasets or gather new ones, and to examine places in the solar system that might harbour such evidence. Rigorous enquiry into solar system technosignatures won’t just expand scientific understanding – it will help us prepare. And preparation, after all, is better than ignorance.
Author Narrative
- Ravi Kopparapu is a planetary scientist.
- Jacob Haqq Misra is an astrobiologist at the Blue Marble Space Institute of Science in Seattle. He is the author of Sovereign Mars (2022).
Notes
- This paper is rather a jumble that doesn't keep on topic.
- I suppose it's necessary to demonstrate that alien intelligence is likely before we start looking for it nearby. But that's the story for another paper. No doubt there are several on Aeon. So, most of the paper is irrelevant.
- The Editor has doubtless dug these out and linked them in!
→ Aeon: Video - Voyagers
→ Aeon: Video - 5,000 exoplanets
→ Aeon: Video - Oppy: The life of a rover
→ Aeon: Folger - Our aquatic universe
→ "Skibba (Ramin) - To find aliens, we must think of life as we don’t know it"
→ Aeon: Powell - The search for alien tech
→ "Green (Jaime) - Uncertain contact"
→ Aeon: Video - Brilliant noise
→ Aeon: Video - ʻOumuamua: our first interstellar visitor
→ Aeon: Video - A fictive flight above real Mars
- There are links to non-Aeon papers, but I've not had time to look at them.
- Biosignatures - even if they can correctly be distinguished from abiotic phenomena - are hardly evidence for an advanced civilisation (bacteria will do).
- Technosignatures are more interesting, but - again - nothing to do with visitations.
- As one reviewer remarked - why not mention UFOs?
- The trouble with this (as the authors intimate) is that it's the province of the lunatic fringe. But the authors seem to be suggesting that real scientists ought not to be put off by this. Fair enough - but then why not have a go?
- I suppose the point is to encourage the authors' colleagues (or employers) to take the question of a local search for extraterrestrial contact more seriously. But Aeon readers can't be expected to be excited by this.
- There are a few Aeon Comments, but they aren't very insightful. They are mostly unimpressed. I agree.
- While the research is part-funded by the Templeton Foundation, there's no evident religious bias. I do think - though - that the authors are right that while evidence of remote civilisations would be of conceptual interest and might lead to a revolution in our understanding of our place in the universe, evidence of 'visitation' would lead to geopolitical turmoil and wastage on - likely futile - defence strategies.
- I suppose this relates - vaguely - to my Notes on Narrative identity, Naturalism, Religion and Transhumanism.
Comment:
Text Colour Conventions (see disclaimer)
- Blue: Text by me; © Theo Todman, 2025
- Mauve: Text by correspondent(s) or other author(s); © the author(s)