Humans have long wondered if they are alone in the universe, or if there is intelligent life somewhere out there trying to make contact.
Now that scientists have developed instruments capable of picking up and homing in on signals they don't quite yet understand, humanity might be inching closer to answering those questions.
The possibility that someone out there is trying to communicate with us has led to various efforts to analyze sounds produced by our universe. Of these sounds, fast radio bursts (FRBs) are one of the most intriguing types. Discovered only rather recently, FRBs, or “cosmic whistles,” are flashes of energy — radio chirps — that exist for just a few milliseconds at a time but can generate as much energy as 500 million suns.
Though no FRBs have been detected emanating from our own galaxy, researchers have picked up a signal from a galaxy that is three billion light year away:
The enigmatic radio signal in question is called FRB 121102, and it was discovered two years ago by Shami Chatterjee of Cornell University’s Department of Astronomy and his colleagues. This particular FRB was interesting because the signals broadcasted seemed to be repeated, which narrowed down the possible sources of FRBs.
The team was able to locate the source of FRB 121102 using very powerful satellites. First, they dedicated all 27 of the 82-foot-wide satellite dishes at New Mexico’s Very Large Array radio observatory to the task. After a period of six months that included 83 hours-worth of observations, the team managed to capture nine images of FRB 121102. Next, they used the powerful Gemini optical telescope to narrow the source of FRB 121102 to a dwarf galaxy about three billion light-years away from Earth.
At that point in their research, Chatterjee says the signal went into "hyperdrive", with signals coming every hour, and they were able to determine the sound's origin to be the center of the dwarf galaxy, which was home to a supermassive black hole.
This means that the fast radio bursts could be caused by the black hole itself, or they could be the result of something else near it, like the gaseous remnants of a supernova in the black hole or a neutron star orbiting it.
Having identified the signal and where it originates, Chatterjee and other scientists are left to wonder what it means.
“One possibility is that it has something to do with the evolution of the universe,” he said. “It’s something that happened three billion years in the past, when the universe was slightly different than it is today. That’s weird. It was going on three billion years ago, but not three million years ago?”