Scientists think it is unlikely that our first contact with extraterrestrials will be like the movies. It will probably be the detection of a strong and atypical signal.
For decades, science fiction writers have strived to prepare us for possible contact with extraterrestrials. Their efforts are dominated by several recurring themes. There’s the invasion by a warlike species, there’s the highly evolved species trying to communicate with our primitive species, there’s the benevolent aliens coming to save us from ourselves, and there’s the mischievous anal explorers and medical experimenters.
But these examples are highly unlikely to represent first contact, according to new ideas and research. Not only because they might be completely unrealistic, but also because of what could motivate another species to contact us and how that would alter the observational signal it uses to announce its presence.
A new piece of research titled “The Eschatian Hypothesis” by David Kipping will be published in the Monthly Notices of the Royal Astronomical Society. Kipping is well known in space circles as the director of Columbia University’s Cool Worlds Laboratory. He also has a popular YouTube channel called Cool Worlds. Cool Worlds magazine focuses on exoplanets in wide orbitsbut also addresses technosignatures and extraterrestrial intelligences (ETI).
In the new paper, Kipping explains that the first detection of an astrophysical object is generally not representative of its entire type. Instead, we tend to first detect objects with large observational signaturesdue to our detection methods and their biases. The history of astronomy is full of examples.
The history of exoplanet detection illustrates this phenomenon. The first exoplanets were discovered in the early 1990s, orbiting pulsars. But we now know that these cases were not representative. In the NASA Exoplanet Archive, with more than 6000 exoplanets, were found less than 10 orbiting pulsars. They were detected because pulsars are like cosmic lighthouses with exceptional temporal precision, and exoplanets in orbit have noticeably altered that precision. This had nothing to do with the abundance of these types of planets.
This also applies to stars that we can see with the naked eye. Depending on the circumstances, we may observe around 2500 stars in the night sky. Approximately a third of them are evolved giants. But not nearly a third of all stars are evolved giants; their observation signal is simply too strong. Our naked-eye detection bias makes them stand out, while our closest neighbor is invisible because it is a red dwarf, a very abundant type of star.
Kipping extends this phenomenon to first contact. “If history is any guide, perhaps the first signs of extraterrestrial intelligence are also examples highly atypical and ‘shrill’ of their wider class“, he writes. Kipping cites supernovae as an analogy. They are extraordinarily bright and easily observed because they are in the process of ending.
“Motivated by this, we propose the Eschatian Hypothesis: that the first confirmed detection of an extraterrestrial technological civilization will likely be an atypical example, exceptionally ‘strong’ (i.e. producing an abnormally strong technosignature) and possibly in a transient, unstable or even terminal phase.”
Escatiano comes from the word eschatology. It is part of the world’s religions associated with death and judgmentand the end of humanity.
The strong signals in the Eschatian Hypothesis may be a byproduct of a declining civilization. Some scientists have proposed that human civilization is become unstable due to climate change and that global warming and its increasing carbon content, as well as other chemical pollutants, could be seen by the ETI as the strong technosignature of a civilization in decline.
Or the signs in the hypothesis could be a purposeful and unmistakable cry for help. In a YouTube video, Kipping questions whether the famous “Wow!” sign 1977 could have been a deafening cry for help from a civilization approaching its own end.
The Eschatian Hypothesis has implications for how we search for and understand phenomena in the cosmos, especially technosignatures. It is very likely that we will detect intense signals that are not representative of the population of extraterrestrial intelligences (ETIs), if such a thing exists.
“In practical terms, the Escatian Hypothesis suggests that high-cadence, wide-field surveys, optimized for generic transients, can offer our best chance of detecting civilizations so intense and ephemeral”, writes Kipping.
Kipping asserts that we are reaching the point where the sky is under continuous surveillance in the time domain. Observatories like the Vera Rubin Observatory and the Sloan Digital Sky Survey continually monitor the sky for changes. This is preferable for detect the atypical signal which will probably be our first detection of an ETI.
Rather than targeting narrowly defined technosignatures, eschatological search strategies would prioritize broad, anomalous transients—in flow, spectrum, or apparent motion—whose luminosities and timescales are difficult to reconcile with known astrophysical phenomena,” writes Kipping. “Thus, agnostic anomaly detection efforts would offer a suggested path forward,” he concludes.
There are a myriad of reasons why humanity’s first encounter with another civilization won’t be in the form of gigantic invasion ships hovering over our cities, benevolent, evolved beings coming to save us, or kinky anal probes from some obscure corner of the cosmos. They are fantastic science fiction ideas that capture our attention with an exaggerated sense of drama. (But they’re fun, aren’t they?)
Instead, it will probably be a very strong and very atypical signal coming from somewhere else in the cosmos.
“The history of astronomical discoveries shows that many of the most detectable phenomena, especially the first detections, are not typical members of their broader class, but rather rare and extreme cases with disproportionately large observational signatures,” Kipping writes.
