A mysterious signal that was emanating from space was traced to its origins after nearly a yearlong hunt by scientists.
The signal was coming from a telephone or even a computer located somewhere in Australia, according to two studies published in the journal Nature Astronomy.
“It is human-made radio interference from some technology, probably on the surface of the Earth,” Sofia Sheikh, an astronomer at the University of California, Berkeley said.
The signal was first detected by a 210-foot radio telescope at the Parkes Observatory in New South Wales, Australia. The dish, like many Australians call it was the subject of a 2000 film of the same name, starring Sam Neill.
The radio telescope is part of Breakthrough Listen, the largest-ever scientific research program to listen for extraterrestrial “technosignatures.”
The signal, which lasted about five hours at 982 megahertz, was at a frequency normally reserved for aircraft communications. But the researchers eliminated that possibility since there were no aircraft in the area.
“This signal mimicked exactly what it is they were trying to find. And it’s really rare. I mean, it’s the first time in years that they’ve seen something like this,” Jason Wright, a professor of astronomy and astrophysics who is director of the Penn State Extraterrestrial Intelligence Center said.
It had clear signs of being produced by technology, he says. It was at one specific frequency, whereas natural signals always show up over a range of frequencies. That alone is not surprising, he says, because there are lots of easily identifiable human-made signals that need to be sifted out all the time.
However, the signal didn’t stay at the same frequency. “That’s something that you expect from things that are actually in space,” he says, because the Earth’s spin causes a Doppler shift in the frequency.
“Based on how the frequency is drifting it suggests it’s probably some cheap piece of electronics using a quartz oscillator,” Wright added.
It’s not the first false alarm for scientists who search for extraterrestrial intelligence.
In 2015, Russian astronomers using a radio telescope in Zelenchukskaya, at the foot of the Caucasus Mountains north of Georgia, discovered an interesting beam-shaped signal. That turned out to be from a Russian military satellite.