Alien hunters in most extensive search of stars turn up nothing

The close encounter will have to wait. Astronomers have come up empty-handed after scanning the heavens for signs of intelligent life in the most extensive search ever performed.

Researchers used ground-based telescopes to eavesdrop on 1,327 stars within 160 light years of Earth. During three years of observations they found no evidence of signals that could plausibly come from an alien civilisation.

The only signals picked up by the Green Bank telescope in West Virginia and the Parkes telescope in Australia had more Earthly origins, the scientists found, with mobile phones and other terrestrial technology providing plenty of noise, and more transient signals coming from overflying satellites.

“It’s quiet out there,” said Danny Price, an astronomer at the University of California, Berkeley, and a member of the Breakthrough Listen project, which aims to scan a million nearby stars, the entire plane of the Milky Way, and 100 neighbouring galaxies for radio and optical signals.

“We haven’t found anything in the data, but I’m certainly not giving up hope. There are still so many more stars to look at and more search approaches to consider.”

The scientists hope to spot “technosignatures”, which could reveal the presence an alien civilisation. These powerful electromagnetic signals are distinct from the various bursts of natural radiation that pour constantly through the galaxy.