For decades, science fiction writers have tried their best to prepare us for eventual contact with aliens. Their efforts are dominated by several recurrent tropes.
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 come to save us from ourselves, and there’s the mischievous anal-probers and medical experimenters.
But those examples are highly unlikely to represent first contact, according to new thinking and research.
Not just because they may be totally unrealistic, but because of what might motivate another species to contact us, and how that alters the observational signal they use to announce their presence.
A new research article titled “The Eschatian Hypothesis” by David Kipping will appear in the Monthly Notices of the Royal Astronomical Society. Kipping is well-known in space circles because he’s the director of the Cool Worlds Lab at Columbia University.
He also hosts a popular YouTube channel called Cool Worlds. Cool Worlds focuses on exoplanets on wide orbits, but also touches on technosignatures and extraterrestrial intelligences (ETI).
In the new paper, Kipping explains that the first detection of an astrophysical object is usually not representative of the overall type.
Instead, we first tend to detect things with large observational signatures, due to our detection methods and their biases. The history of astronomy is full of examples.
The history of exoplanet detection illustrates the phenomenon. The very first exoplanets were found in the early 1990s orbiting pulsars.
But now we know that those were not representative. In the NASA Exoplanet Archive of more than 6,000 exoplanets, fewer than 10 were found around pulsars. They were detected because pulsars are like exquisitely-timed cosmic lighthouses, and orbiting exoplanets altered that exquisite timing noticeably. It had nothing to do with how plentiful these types of planets are.
It’s also true of the stars we can see with the naked eye. Depending on circumstances, we can see about 2,500 stars in the night sky. About one-third of them are evolved giant stars. But nowhere near one-third of all stars are evolved giants, it’s just that their observational signal is so strong. Our naked eye detection bias makes them jump out at us, while our nearest neighbour is invisible because it’s a red dwarf, a very plentiful type of star.
Kipping extends this phenomenon to first contact. “If history is any guide, then perhaps the first signatures of extraterrestrial intelligence will too be highly atypical, “loud” examples of their broader class,” he writes. Kipping points to supernovae as an analogy. They’re extraordinarily bright and easily observed because they’re in the process of termination.
“Motivated by this, we propose the Eschatian Hypothesis: that the first confirmed detection of an extraterrestrial technological civilization is most likely to be an atypical example, one that is unusually “loud” (i.e., producing an anomalously strong technosignature), and plausibly in a transitory, unstable, or even terminal phase.”
Eschatian comes from the word eschatology. It’s the part of the world’s religions that is associated with death and judgement, and with the end of humanity.
The loud signals in the Eschatian Hypothesis could be a by-product of a civilization in decline. Some scientists have proposed that human civilization is becoming unstable due to climate change and that the warming climate and its growing carbon content, as well as other chemical pollutants, could be viewed by ETIs as the loud technosignature of a civilization in decline.
Or the signals in the hypothesis could be a purposeful, unmistakable cry for help. In a YouTube video, Kipping wonders if the famous Wow! signal from 1977 could have been the very loud cry for help from a civilization approaching its own eschaton.
The Eschatian Hypothesis has ramifications for how we search for and understand things in the cosmos, especially technosignatures. We are most likely to detect loud signals that are not representative of the ETI population, if there is such a thing.
“In practical terms, the Eschatian Hypothesis suggests that wide-field, high-cadence surveys optimized for generic transients may offer our best chance of detecting such loud, short-lived civilizations,” Kipping writes.
Kipping says that we’re getting to the point where the sky is under continual surveillance in the time domain. Observatories like the Vera Rubin Observatory and the Sloan Digital Sky Survey watch the sky continuously for changes. This is preferable for detecting the atypical signal that will most likely be our first detection of an ETI.
“Rather than targeting narrowly defined technosignatures, Eschatian search strategies would instead prioritize broad, anomalous transients – in flux, spectrum, or apparent motion – whose luminosities and timescales are difficult to reconcile with known astrophysical phenomena,” Kipping writes. “Thus, agnostic anomaly detection efforts would offer a suggested pathway forward,” he concludes.
There are a multitude 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 come to save us, or whacky anal-probers from some dark backwater of the cosmos. Those are fantastical sci-fi ideas that grab our attention with an overwrought sense of drama. (But they’re fun though, aren’t they?)
Instead, it’ll likely be a very loud, very atypical signal from somewhere else in the cosmos.
“The history of astronomical discovery shows that many of the most detectable phenomena, especially detection firsts, are not typical members of their broader class, but rather rare, extreme cases with disproportionately large observational signatures,” Kipping writes.
Wow!
Written by Evan Gough/Universe Today.
