We have been seriously researching extraterrestrials for 60 years now. This research is rapidly expansion. And it forces scientists to define, much more clearly, what evidence for an extraterrestrial civilization might even look like.
The definition has just become much broader, thanks to a study published on May 31 that lists a bunch of new “technosignatures” – things in space that could signify the existence of extraterrestrial technology and therefore an entire civilization, alive or extinct.
Pollution from alien farms and factories. Giant habitable structures containing whole stars. Explosive bursts of radiation from the engines of high-tech spacecraft belonging to other sentient species. These are just some of the signatures in the new list, compiled by a team led by Jacob Haqq-Misra, an astrobiologist at the Blue Marble Space Institute of Science in Seattle.
The new study, which has been peer-reviewed and accepted for publication in the scientific journal Acta Astronauticsreads like a sketch of the first act of a sci-fi movie, where daring explorers glimpse fleeting evidence that humanity is not alone in the cosmos.
But the study is not fiction. Synthesizing contributions from dozens of researchers from all disciplines, it’s serious science — and it could help guide multibillion-dollar telescope surveys and space probe missions for decades to come.
Outside experts praised the study. “There are no gaping holes in this list of technosignature research strategies,” Douglas Vakoch, who heads the research organization METI International in San Francisco, told The Daily Beast. “We have a sufficiently complete list for us to start observing.”
The are holes, although they may be small. Scientists who weren’t part of the Haqq-Misra study are eager to add to the list of technosignatures, all to give us the best chance of recognizing aliens if and when we finally encounter them.
Still, even a somewhat incomplete count of new technosignatures is a big improvement. As a scientific discipline, the search for extraterrestrial intelligence – SETI – began in the 1960s, when early scientists began listening to random noise in the galaxy, hoping to hear a repeating patterned signal that could only come from intelligent beings. .
“There are no gaping holes in this list of technosignature search strategies. We have a sufficiently complete list for us to launch into observation.”
— Douglas Vakoch, METI International
In the past two years alone, we’ve expanded SETI to include deliberate scanning for telltale flashes of man-made lasers, the kind aliens might use to communicate between planets or even power certain types of spacecraft.
New telescopes, probes, instruments and search algorithms – some ready to deploy, others still in development – give us reason to add a whole bunch of additional SETI signatures to radio signals and laser flashes. Think of the accepted list of these signatures as a kind of unofficial recognition guide for extraterrestrials, like a cosmic version of the guides people carry when they go birdwatching.
New technosignatures approved by Haqq-Misra and his co-authors include: signs of industrial pollution in the atmosphere of a distant planet; the dense night lights of sprawling alien cities; and the distinctive reflections of huge solar panels that could power these cities.
Then there are the possible structures in space: extraterrestrial space stations or, more grandiosely, gigantic space colonies or energy generators partially or completely enclosing a distant star. We should also look for radiation pulses from extraterrestrial spacecraft engines traveling to or from an extraterrestrial homeworld or its off-world bases.
Each of the study’s 11 authors — who run the scientific gamut from academic astronomers to NASA advisers and private sector researchers — has their own favorite technosignature. The thing they think we should look for the most.
Haqq-Misra told The Daily Beast he was most excited about the pollution. Using new instruments, including NASA’s $10 billion James Webb Space Telescope and the Large Exoplanet Interferometer, a probe under development in Europe, it is possible to study the atmospheres of distant exoplanets far beyond our own solar system.
Certain light patterns could suggest the presence of pollutants like nitrogen dioxide, a possible sign of agriculture, industry, and transportation technologies. “I’m excited about atmospheric technosignatures because they’re completely unexplored, and we can point to examples on Earth today of how technology has changed. our atmosphere,” Haqq-Misra said.
Ryan Felton, an astrobiologist at the Catholic University of America in Washington, D.C. and co-author of the technosignature study, told The Daily Beast that he was very excited to spot a Dyson sphere or a Dyson swarm. (Felton works with NASA but stressed that he does not speak for the space agency.)
A Dyson sphere, named after the late physicist Freeman Dyson, is a theoretical structure enveloping a star entirely, like a vast eggshell. A very advanced civilization could build something like this in order to create an unimaginable living space with essentially unlimited power. A Dyson swarm is basically fragments of a Dyson Sphere – separate habitable platforms revolving around a star.
Finding proof of such advanced technology, perhaps using a telescope like the JWST, would be like looking at our own possible technological future, Felton said. “How would this exhibition influence our own technological paths in the future? Seeing our response to these scenarios would be fascinating.
There are technosignatures that might be just as useful as those cited by Haqq-Misra and his co-authors, but are not in the new study. Wade Roush, popular science speaker and non-fiction book author aliens, mentioned a big omission. “It struck me that the list did not include interstellar objects passing through our solar system,” he told The Daily Beast.
In other words, alien probes looking for we. Or abandoned probes that has tried was looking for us potentially thousands or millions of years ago and ran out of power before drifting endlessly across the galaxy. ET’s space trash can.
Some scientists, including Harvard physicist Avi Loeb, have sparked controversy in recent years by claiming that ‘Oumuamua – a strange, possibly 300ft object that streaked through the solar system after arriving from interstellar space in 2017 – is a sign that intelligent extraterrestrials might exist. While most astronomers assume that ‘Oumuamua is a rock with a strange trajectory, Loeb insisted that we should study it as a possible spacecraft.
Ravi Kopparapu, a planetary scientist at NASA’s Goddard Space Flight Center in Maryland who is another Haqq-Misra co-author, told The Daily Beast that we should expect the unexpected no matter what. is on the accepted list of signatures.
We could add a bunch of technosignatures to our galactic search model and still stumble upon something that feels as proof of an extraterrestrial civilization, but does not correspond to any of our preconceived ideas. “I suspect that the first detection could come from an unexpected source, an anomaly that doesn’t match the data,” Kopparapu said.
For this reason, it’s really important for SETI scientists to keep an open mind. “The biggest challenge we face in finding extraterrestrial technosignatures is imagining extraterrestrial civilizations radically different from our own civilization,” Vakoch said.
Haqq-Misra conceded that we can’t even begin to guess if, and how, we might finally detect aliens, even after all these decades of searching. “I can’t say anything about the likelihood of finding particular technosignatures, because we just have no idea how common life and technology is in our galaxy,” he said.
The only way to guarantee we never find AND is not to seek, of course. “That’s the reason we have to search!” said Haqq-Misra. While we’re searching, it’s handy to have an alien reconnaissance guide on hand. And even more practical to keep this guide as up to date as possible.