Astronomers searching for the origins of a mysterious blast of radio waves have solved the puzzle: a tiny galaxy billions of light years from Earth, Space reports. So-called FRBs (fast radio bursts) twinkle in the sky for only a millisecond, yet they radiate more energy than the sun ever could in 10,000 years. Although scientists have pinpointed only 18 of the bursts, they believe they flicker somewhere every 10 seconds or so. Since FRBs were first discovered in 2007, astronomers have been hunting their source. They found some answers thanks to an FRB that repeats—the only known one to do that, reports the Verge. Using 27 radio telescopes in New Mexico arrayed in a Y shape, scientists captured high-resolution images of the bursts. Writing in the journal Nature, researchers say they tracked a glimmer of light to a distant dwarf galaxy, a mass of stars smaller than our own Milky Way.
By measuring the galaxy's movement through its light, they were able to determine its distance from Earth—3 billion light years. The finding left the telescope set a bit, er, underwhelmed. "We were not sure what to expect, but I think the whole team was surprised to see that our exotic source is hosted by a very puny and faint galaxy," researcher Cees Bassa says, per Space. Still unsolved: What's causing the waves. One theory is that a black hole belching light-speed jets of particles and "blobs of plasma" may sometimes create a bright flash, per the Verge. Another idea is that those plasma blobs are magnifying pulses from a "magnetar, " a star with a strong magnetic field, allowing us to see the light bursts on Earth. (Another sort of wave —this one massive—recently made headlines.)