Fast radio bursts are brief, intense flashes of radio waves that have puzzled astronomers since their discovery nearly 20 years ago. Now, researchers using the MeerKAT radio telescope in South Africa have detected one such burst, designated FRB 20240304B, and tracked it back to its source.
The burst showed a high degree of dispersion, meaning its different frequencies arrived at slightly different times due to passing through electrically charged material in space. By measuring this effect, the team estimated the signal had travelled an enormous distance.
When the astronomers attempted to locate the host galaxy using large ground-based telescopes such as the Keck Telescopes, they found nothing visible. The galaxy was simply too faint. They then turned to the James Webb Space Telescope (JWST), whose infrared camera revealed a tiny galaxy very close to the burst's position.
Further analysis of the galaxy's light spectrum confirmed it existed when the universe was only one-fifth of its current age, more than 10 billion years ago. The galaxy is small and rich in young stars, providing clues about the environment that produced the powerful millisecond-long flash.
The research team included scientists from the University of Sydney and made use of the MeerTRAP system, a real-time transient detection system on MeerKAT. The findings add a new data point to the ongoing effort to understand what causes fast radio bursts and how they relate to the evolution of galaxies.