Is there life out in space? NASA/Robert Markowitz | Courtesy

When junior Shane Smith started looking for a summer research internship last year, he never expected to work on a project ana­lyzing radio signals that could provide proof of extrater­res­trial life. 

 “I didn’t really know that there was actually a sci­en­tific com­munity that was looking for aliens,” Smith, a physics major, said. “Usually when you think of that, you think of fringe sci­en­tific things where, ‘Oh a UFO was spotted,’ and stuff like that. It’s not like that at all.”

Smith was a research intern for the Break­through project at Berkeley Search for Extrater­res­trial Intel­li­gence Research Center based at the Uni­versity of Cal­i­fornia-Berkeley. The program, which seeks to dis­cover evi­dence of extrater­res­trial life, was founded in 2015 by Dr. Stephen Hawking and Yuri Milner, an internet investor. 

As an intern, Smith par­tic­i­pated in Break­through Listen, a project that studies tech­nosig­na­tures, which are signs of past or present tech­nology. He studied a radio signal coming from the direction of Proxima Cen­tauri, a red-dwarf star in the Alpha Cen­tauri system. At 4.24 light-years away, it is the closest known star to the sun but faint or invisible to the naked eye. 

“The project that I was working on was looking for the radio spectrum for these types of signals that might show a sign of some sort of intel­ligent civ­i­lization pretty far away or even close to our own solar system,” Smith said.

The project gar­nered national attention. Last month, the New York Times ran a story on the mys­te­rious radio signals and men­tioned Smith by name. According to the Times, the signal Smith was working on was recorded by the Parkes radio tele­scope in New South Wales, Aus­tralia on April 29, 2019. The data was orig­i­nally recorded to monitor Proxima Cen­tauri for violent solar flares.

The signal, coming in at 982.002 MHz, is the first serious can­didate Break­through Listen has had, according to the Times. 

This radio tele­scope covers a large range of fre­quencies and is highly sen­sitive. Because the tele­scope picks up enormous amounts of data, Break­through Listen uses two filters to isolate unique signals.

The first filter ana­lyzes if the signal is drifting in fre­quency, which weeds out signals coming from Earth. The second filter ensures that the signal is coming from a spe­cific part of the sky.

“We look at the source for a certain amount of time and then off the source for a little bit,” Smith said. “And if it’s there when you’re looking toward the source but not when you’re looking away, it sug­gests that it’s coming from that localized point in the sky.”

Even if a spe­cific signal makes it through these filters, it doesn’t guar­antee it’s a sign of extrater­res­trial intel­li­gence. The project then ana­lyzes the signal further to ensure it’s not coming from a satellite.

“Basi­cally, the buzz around the Proxima Cen­tauri obser­va­tions is that we haven’t really been able to con­clu­sively say that it is human-gen­erated inter­ference,” Smith said. “There’s just more analysis that needs to be done on it.”

While this radio signal is most likely human inter­ference, there is still a pos­si­bility that life exists outside our planet. 

“There are likely bil­lions of Earth-like planets in our Milky Way galaxy alone. What are the chances that they’re all empty?” Timothy Dolch, asso­ciate pro­fessor of physics, said. “It’s hard to assign a number to the prob­a­bility, but whatever that number is, it’s not zero.” 

Smith credits his work on radio astronomy research with Dolch for sparking his interest in the subject. Smith has worked with the physics department on several projects, including ana­lyzing data for the North American Nanohertz Obser­vatory for Grav­i­ta­tional Waves. His expe­rience in radio astronomy proved useful during his internship. 

“His expe­rience with pro­gramming, data analysis, and radio tele­scope hardware all came together and made him shine,” Dolch said. 

While the radio signal may simply prove to be human inter­ference, Smith said he is excited to have been able to par­tic­ipate in the field, and he con­tinues to work part-time with Break­through Listen on further analysis. 

“I just think it’s really cool to be involved in this research. Not many people really know about it or that it’s like a respected science.” Smith said.