The Most Distant Fast Radio Burst Yet Traveled 10 Billion Years

Astronomers have detected a fast radio burst that traveled for more than 10 billion years to reach Earth, believed to be the most distant such burst on record. The Guardian

The event is called FRB 20240304B. It was first picked up on March 4, 2024. Its light-travel time is more than twice the previous distance record.

That means the burst left when the universe was about 3 billion years old. It crossed roughly 80% of cosmic history before detection.

The detection was made with the MeerKAT radio telescope in South Africa. The study was published in Science. Researchers then used NASA's James Webb Space Telescope to identify the host galaxy.

Webb data show the source galaxy is young, very small and actively forming stars, with low metal content. In astronomy, metals means elements heavier than hydrogen and helium. The result ties a very early burst to a dwarf-like galaxy environment.

Fast radio bursts are brief, millisecond-long pulses of radio energy from outside our galaxy. More than 10,000 have been detected since their discovery in 2007.

The previous record holder was FRB 20220610A. Its light traveled eight billion years to reach Earth. It was found on June 10, 2022 by the ASKAP radio telescope in Australia. UC Santa Cruz

That burst was reported as four times more energetic than closer fast radio bursts. Its 8-billion-year-old signal was later linked to merging galaxies.

The broader context here is the size of the step forward. Doubling the distance extends the line of sight through more intervening ionized plasma and large-scale structure. For researchers who use dispersion, scattering and Faraday effects to probe distant space, how radio waves are delayed, blurred and twisted, one signal from this far back carries real weight.

Looking at what this means for host-galaxy work, the Webb result is as important as the radio detection. A small, star-forming, low-metal host in the early universe narrows the possible environments that can produce these bursts, without settling what causes them. The combination is likely to become the standard approach: wide-field radio telescopes to find them, infrared space telescopes to pin down where they came from.