How would you feel if, after many decades of searching, we found signs of extraterrestrial intelligence?
Would you be consumed by wonder & excitement or does the thought of making contact with an unknown life force somewhere out in the universe fill you with fear & trepidation?
And what impact would this discovery have on us collectively, would it unite us or divide us here on Earth?
“Maybe the search for extraterrestrials actually tells us more about ourselves than anything,” says world’s renowned astronomer & deputy executive of the International Centre for astronomy Research, Professor Steven Tingay, who is pondering these and other weighty existential questions in the course of his research.
Tingay & his CSIRO colleague Dr. Chenoa Tremblay are involved in the deepest & broadest search yet for signs of alien life, because of the capabilities offered by the Murchison Widefield Array (MWA), the highly sensitive, low frequency radio reflector with a fantastically wide field of view that’s supporting a trove of latest scientific endeavors from its whisper quiet location in inland Western Australia.
So far, no signals are detected to suggest we aren’t alone. But with the MWA now allowing much expanded searches to be conducted alongside other astrophysical investigations, search for extraterrestrial intelligence commonly mentioned as SETI, is certainly ramping-up.
For example, it’ll little increase fresh questions on our cosmic exclusivity generated by NASA’s latest mission to Mars, where Perseverance rover is collecting rock & soil samples which will be probed for signs of ancient microbial life.
In 2018, MWA was used to scan part of Vela constellation, which is known to cover at least 10 million-star systems.
Within this field are 6 known exoplanets: planets that orbit around other stars, just like the Earth orbits around the Sun, that could potentially offer the perfect conditions for hosting life.
Through this & 2 previous surveys, Tingay & Tremblay examined 75 known exoplanets, searching for narrow-band signals consistent to radio transmissions from intelligent civilizations, with an extra 144 exoplanets examined in research to be published soon.
Fortuitously, MWA allows the search for extraterrestrial intelligence to piggy-back onto science that’s already happening, offering, as Tingay describes it, “two bits of science for one.”
As a part of her PhD research, Chenoa used radio reflector to observe molecular signatures from stars, gas & dust in our galaxy in the hopes of detecting the complex molecules that are the precursor to life.
The pair realized that these data might be simultaneously used for the look for radio signals from advanced civilizations.
Credit: Goldsmith/MWA Collaboration/Curtin University
“It’s a really high-return, low-effort route at this stage, which suggests that if you strike it lucky it hasn’t really cost you all that much along the way,” Tingay explained. “So that’s almost a perfect scenario for science.”
So, what exactly are they trying to find in their MWA surveys?
“We’re not 100 percent sure,” Tremblay admitted.
“It’s like asking a toddler to go and find an object in the house and they very excitedly go and run and look under the couch then come back with big eyes and go, ‘What does it look like?’
In general, we’re looking for intense signals that show-up in very narrow wavelength ranges and it might be anywhere in the electromagnetic spectrum. We use models from our understanding of the cosmos and what the signals have looked-like so far to narrow down the search.
“The benefit of looking at lower radio frequencies or very long wavelengths is that they pass through the Earth’s atmosphere so we will build ground-based telescopes. They're travelling through dust & gas which may be within the galaxy. So that means we will probe much further across larger distances than if we’re looking at much higher energies or smaller wavelengths.”
While 2018 survey was much more comprehensive than ever before, Tingay is keen to point-out that it had been still just a drop by the ocean.
“Our galaxy contains billions and billions of stars, so 10 million out of multiple billions is a very small fraction,” he explained.
“If that entire search space was represented by the Earth’s oceans, we’re talking about searching about a swimming pool worth of water out of the ocean. Having said that, what we did was hundred times better than anyone had done previously and the previous best was also us!
“So, what we’re doing is proving up techniques which will allow us to go further & deeper as we develop more powerful telescopes. And the next step in that progression is the Square Kilometer Array.”
The MWA is effectively the warm up act for the Square Kilometre Array, which started its construction phase in Western Australia & South Africa, following more than a decade of design & engineering work by many experts from more than a dozen countries.
This global mega science project will deliver two largest & most complex networks of radio telescopes ever built, designed to unlock a number of the foremost fascinating secrets of our Universe and it no doubt has SETI enthusiasts very, very excited.
Asked to sum-up his own reaction should this new frontier of astronomy confirm signs of extraterrestrial intelligence sometime soon, Tingay is quick to respond: “I’ll rush to the telescope to get more data!”
Researcher profiles
John Curtin Distinguished Professor Steven Tingay is Deputy Executive of International Centre for Astronomy Research (ICRAR) and leads its Curtin University node. He’s also the director of Murchison Widefield Array.
Professor Tingay is an internationally renowned expert in astronomy & astrophysics and his research encompasses building and using radio telescopes also as astrophysical interpretation.
He has been at the forefront of a number of the elemental advancements made possible by MWA, including the search for the first stars 13 billion years ago also the look for extraterrestrial life. Professor Tingay was named the joint winner of the Scientist of the Year award at the 2020 Western Australian Premier’s Science Awards.
Dr. Chenoa Tremblay completed her PhD in Physics at Curtin University in 2018. She is now a Postdoctoral Researcher with CSIRO (Australia’s National Science Agency) studying the magnetic fields & chemistry of stars & star-forming regions. For her thesis, she used the Murchison Widefield Array to-look for molecules with low-energy transmissions in inter, which also helped set the bounds on the 1st low-frequency look for extraterrestrial signals towards known exoplanets. Previously, Dr Tremblay was a special projects manager with Australian-based mineral analysis company MinAnalytical where she developed new technologies & software for laboratories supporting the mining industry.
Article originally published on Sci Tech Daily.
