Are aliens with a quirk of The sunthe force of gravity to transmit information over an interstellar communications network? For the first time, astronomers have explored this intriguing possibility, looking for signals from hidden non-human probes orbiting the sun.
So far, the method hasn’t revealed any signs of extraterrestrial extraterrestrials, but it represents a promising new way of hunting extraterrestrials as part of the Search for Extraterrestrial Intelligence (SETI).
The new search strategy is based on the findings of Albert Einstein, who showed in 1915 that gravity distorts the fabric of spacetime. This means that massive objects like stars and galaxies bend light around them. Known as gravitational lensing, this effect allows scientists to see extremely distant objects whose light has been distorted by giant foreground galaxies and galaxy clusters.
“It’s like a magnifying glass” Nicholas Tusaya graduate student at Penn State, opposite Live Science.
With both gravitational lenses and a magnifying glass, magnification works best when a person or detector is positioned at a specific location known as the focal point, he said.
The Sun’s gravitational center starts at about 550 astronomical units (AU), or 550 times the distance between Earth and the Sun, Tusay said. A telescope placed there would have mind-blowing capabilities — it could resolve continents and mountains on a planet orbiting another star, he added.
“Light goes both ways,” Tusay said. “If you can magnify light coming to you, you can magnify light going out.”
This means that gravitational lensing can also be used to efficiently send signals across interstellar distances Scientists have speculated about tech-savvy aliens placing probes at the hotspots of stars, effectively turning them into a gigantic point-to-point communications network.
To test this idea, Tusay and his colleagues used the Green Bank Telescope in West Virginia to conduct six five-minute scans for radio signals emanating from the Sun’s gravitational focus. And what did you find?
“Nothing,” he said. “To be precise: In the frequencies we observed, we did not find any compelling signals that were of extraterrestrial origin during the observation period.”
The results were published in last summer The Astronomical Journal and were presented by Tusay at the 241st meeting of the American Astronomical Society in Seattle last week.
While the results aren’t yet proof of ET, Tusay said it’s possible that extraterrestrial probes placed at the Sun’s gravitational focus just turn on intermittently. And other stars have properties that make them better nodes in a gigantic space internet, so these could be additional search targets, he added. He sees the method more as a proof-of-concept that, if run longer and with more resources, could yield something interesting.
“We keep talking about new ways of searching in the SETI area,” Julia DeMarines, an astrobiologist at the University of California, Berkeley who was not involved in the work, told Live Science. “This is the first time I’ve seen a specific search for this specific possibility of message interception.”
If nothing comes up on a SETI search, it could mean several things, she added, including that nobody is out there communicating, or simply that nobody is communicating that way. Any new search method is always welcome, DeMarines said. “If you don’t look,” she added, “you’ll never know.”