"Breakthrough Listen": Giant Leap for SETI

A $100 million donation will radically speed up the search for artificial signals from the nearest million stars — and from trillions of much farther stars in the 100 nearest galaxies.

Fascination with SETI — the search for extraterrestrial intelligence — waxes and wanes in cycles. Are other technologically able creatures broadcasting their existence to the stars? It's the most important question we know about our role in the cosmos and humanity's long-term future. Are we merely like ants, hopelessly outclassed by vastly older, superior species among the stars? If so, will they help us, harm us, or ignore us? Or are we alone, holding in our own hands the future of conscious life itself?

On July 20th, in an announcement at the Royal Society in London, a tech billionaire and a group of eminent scientists announced a great leap forward in the search to find out. Russian investor Yuri Milner announced that he is committing $100 million to the Breakthough Prize Foundation to carry out radically ambitious SETI projects for the next 10 years, under the name Breakthrough Listen.

"It's just a miracle," SETI pioneer Frank Drake told the New York Times. Said Dan Werthimer, longtime SETI researcher at UC Berkeley and originator of the SETI@home project, "This is beyond my wildest dreams."

The team that Breakthrough Listen has assembled, drawing on UC Berkeley's Search for Extraterrestrial Intelligence Research Center, plans to use about a third of the money to buy some 20 percent of the time on the 100-meter Green Bank radio telescope in West Virginia, as well as substantial time on the 64-meter Parkes radio dish in Australia, for 10 years. These purchases will help ensure a future for both financially imperiled telescopes. Other radio telescopes may be added.

Another third of the funds will go toward developing powerful, sensitive, new receivers and processors to examine billions of narrow frequency channels from 1 to 10 gigahertz. This range spans most of the best radio frequencies: those that get through Earth's atmosphere and are not swamped by cosmic background noise. No protracted search has ever successfully covered such a wide band.

The radio project will use two opposite search strategies. The first is a "targeted search." We now know that most stars have planets. The telescopes will examine the nearest 1 million stars in case radio-emitting civilizations are relatively common — meaning they currently inhabit more than one in a million solar systems — but in case none broadcasts its existence to the cosmos at terribly high power. Looking even closer, the Breakthrough Listen team claims that the project would be able to hear an ordinary air-traffic control radar continuously aimed our way from the nearest thousand stars.

On the other hand, many who have studied SETI search strategy conclude that the most prominent alien signals in our sky are likely to be from extremely powerful transmitters extremely far away. So a "wide sky" sweep is more likely to succeed than a targeted search of individual stars nearby. The logic behind this conclusion seems impeccable even if we know nothing about alien civilizations or their technologies.

To cover this possibility, Breakthrough Listen will also sweep the plane of the Milky Way and the galactic center to encompass more than 100 billion stars in shallower listens. And it will take protracted stares at 100 of the nearest galaxies to cover tens of trillions of stars much farther still. Just one very old supercivilization among all these stars, choosing to display its existence to the cosmos with sufficiently extreme power, would answer the question of whether we're alone right away. Failure to find one would be real evidence that supercivilizations of this kind don't exist.

Breakthrough Listen also plans to carry out an optical SETI search. This project will enhance the sifting of spectroscopic data from Lick Observatory's 2.4-meter Automated Planet Finder telescope (at left) to carry out the deepest search yet for continuous laser signals that might be aimed at our solar system from specific stars under study.

All these projects will gather vast amounts of raw data. Some of its analysis will probably be farmed out to volunteers donating their computers' spare time by way of an app such as SETI@home, which began analyzing data from the Arecibo radio telescope in 1999 and continues going strong today.

Also announced on Monday was Breakthrough Message, a $1 million open competition for ideas about what, if anything, Earth should transmit if Breakthrough Listen finds another civilization. Breakthrough Initiatives says it will not transmit any message until after a global debate on whether calling extra attention to ourselves this way is a good idea.

SETI's Long Perspective

But don't get your hopes up too soon. The Breakthrough Listen planners claim that they'll speed up the search for intelligent life by 100 times over current and recent searches. That's a big improvement, but settling the question of whether we're alone is likely to take generations. The "search space" to be sifted is enormous: many billions of radio, infrared and optical frequencies at each one of many billions of locations on the sky. And then there are such complications as intermittency, frequency drifts, and other factors. In 2004, Guillermo Lemarchand (University of Buenos Aires) calculated that all the SETI searches up to then had scanned only one hundred-trillionth (10^–14) of the cosmic haystack that's waiting to be searched for the needle of an artificial signal.

Scientists with careers to build, and funding agencies with donors to satisfy, prefer to see a return on investment in years or decades, not centuries. So enthusiasm for SETI waxes and wanes, with each new wave of fascination being followed by disillusionment with the boredom of seeing no results. Humanity isn't yet good at projects with very long time horizons.

But for SETI, Breakthrough Listen will help pave the way to getting there.

Video highlights of the press conference (7:15).

New York Times article.

UC Berkeley News article, listing some of the personnel.

A Breakthrough Initiatives backgrounder about SETI and our place in the universe, drawing from the Cosmos TV series (1 hour 30 minutes):