In 2007, astrophysicists at West Virginia University stumbled upon something strange as they reviewed archival data at the Parkes radio telescope in Australia. They found the telescope had detected a powerful flash of radio waves that lasted less than five milliseconds. The signal appeared smeared across a range of frequencies, a sign that the burst had traveled a huge distance—about 3 billion light-years—to Earth. It must have originated from outside the Milky Way, in a distant corner of the universe.
“We’re confused and excited, but it could open up a whole new research field,” Duncan Lorimer, the astrophysicist who co-discovered the signal, said back then. The signal was dubbed a fast radio burst, or FRB.
Lorimer’s prediction was correct. Since that first discovery, scientists have detected about 30 FRBs, coming from all kinds of directions, mined from old data and observed in real time. A decade of careful research has proven these mysterious, high-energy pulses to be real astrophysical phenomena from beyond the galaxy, and not just instrument noise from telescopes, as many first thought. Scientists estimate the bursts occur about 10,000 times a day across the entire sky.
All known FRBs are tantalizing targets, but there’s one in particular astrophysicists love to study: FRB 121102, first detected in 2012. After that, FRB 121102 flashed again—and then again and again and again, eventually racking up more than 150 detected bursts. Before its detection, FRBs were assumed to be one-time events, the products of cataclysmic eruptions or collisions that destroyed their progenitors. The repeating nature of FRB 121102 changed all that. Scientists went after it with hours of observations. Last January, they pinpointed its location to a small galaxy about 2.5 billion light-years from Earth.