Mysterious fast radio bursts help astronomers pinpoint cosmic ‘missing’ matter

Astronomers have used fast radio bursts (FRBs)—brief, powerful flashes of radio waves—to detect previously unseen ordinary matter in the universe, helping solve the long‑standing "missing baryon problem." While dark matter and dark energy dominate the cosmos, only about 10% of ordinary matter had been directly observed. The rest, believed to be spread across the intergalactic medium, was too diffuse to detect—until now. By measuring how FRBs slow as they pass through this "cosmic fog," researchers were able to map and weigh the elusive matter, offering new insights into the universe’s hidden structure.