NASA's Webb telescope traces farthest radio burst found

Fast radio bursts are flashes of radio waves that last a few thousandths of a second, then vanish. They almost never repeat. Radio telescopes in South Africa caught one called FRB 20240304B. Astronomers have now used NASA's James Webb Space Telescope to find exactly which galaxy it came from. The light traveled more than 10 billion years to reach us.

The burst's radio waves passed through gas between galaxies on their way to Earth. Studying that path tells scientists about matter they can't otherwise see. The host galaxy itself was a surprise. It's a small, young galaxy still actively forming stars. Bigger, older galaxies were what some models predicted instead. Fast radio bursts are often linked to magnetars, the dense remains of collapsed stars. But nobody has directly observed one causing a burst.

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Will finding this burst's home galaxy help explain why fast radio bursts happen at all? Most are detected once and never repeat, which makes them nearly impossible to study in real time. Every new one traced to a specific galaxy gives astronomers one more data point. Enough of those points, and the pattern behind these signals might finally come into focus.