The first results from one of the most extensive searches for intelligent life have been released. And, while we didn't find any aliens, the data paves the way for more observations in the near future.
Called Breakthrough Listen, a project that's part of the bold Breakthrough Initiatives programme founded by Russian billionaire Yuri Milner, it's looking for signals being emitted from planets around stars that would be a clear sign of intelligence, similar to the emissions that come from our planet from our artificial technology.
The results were announced at an event called Breakthrough Discuss at Stanford University in California this week, where scientists from various fields are meeting to discuss the chances of finding life (we'll have an overview on the event in the next few days). The research has been submitted in a paper to the Astrophysical Journal.
In the past, the search for extraterrestrial intelligence (SETI) has struggled for funding. Breakthrough Listen represents a whole new chapter though, with observing time being bought on three telescopes. These are the Green Bank Radio Telescope (GBT) in West Virginia, Lick Observatory's Automated Planet Finder on Mt. Hamilton in California, and the Parkes Radio Telescope in Australia.
“Historically in searches for extraterrestrial intelligence, we concentrated on environments that were as likely as possible to be like our own,” Andrew Siemion, director of the Berkeley SETI Research Center, said at Breakthrough Discuss. “In the Breakthrough Listen programme we want to look at as many different types of stars as possible, to leave ourselves open for any possibility that life might emerge on one of these stars.”
These initial results come from the GBT, which spent 400 hours observing 692 stars. The telescope was looking for emissions from the stars in the 1.1 to 1.9 Ghz bandwith. In total, there were 4,768 individual observations, of which 11 were deemed “significant events”. Upon closer inspection, however, these were deemed to have been caused by terrestrial interference, possibly our own satellites in orbit around Earth.
But while the search essentially came up with nothing, it does further refine the search for intelligent life. For example, it shows that of these stars, all within 160 light-years, none were emitting narrow band radio signals between 1 to 2 Ghz – which things like GPS satellites and phones emit.
Breakthrough Listen is a 10-year project to look for intelligent life, so this is only the beginning. It was first announced in July 2015, with the first observations beginning in 2016. Now, it will continue to make its way through a long list of stars it's planning to observe.