Repeating radio signals from a mysterious source in a dwarf galaxy 3 billion light-years away have been detected by astronomers.
Using the Green Bank Telescope in West Virginia, scientists with the Breakthrough Listen initiative—a massive project dedicated to finding signs of intelligent alien life—recorded 15 repeating fast radio bursts (FRBs) on August 26. The discovery was announced as an Astronomer’s Telegram and will be described in further detail in a forthcoming scientific article, according to a statement from Breakthrough Listen.
FRBs last just a few milliseconds and appear to be coming from deep space. Because FRBs have an extremely short duration, and because scientists usually find them in data only after the event has taken place, pinpointing their origin has not been possible.
Since their discovery over 15 years ago, almost two dozen FRBs have been recorded. Most often, they are one-off events, but in 2016 scientists announced in the journal Nature that they had found a repeating radio signal—FRB 121102. By monitoring and tracking this repeating burst, they were able to trace it back to a dwarf galaxy 3 billion light-years away. Still, the source remained elusive. Nothing that we know of in that region of space could be producing these signals.
Now the Breakthrough Listen team has detected 15 more busts coming from FRB 121102. Vishal Gajjar, a postdoctoral researcher at the University of California, Berkeley, where Breakthrough Listen is based, observed the new bursts during a monitoring effort run. Over five hours of observation, he and his colleagues collected 400 terabytes of data over the 4 to 8 GHz frequency band, or C-band, which is mostly used for satellite communications transmissions.
Analysis of the data revealed…