FRB 20240304B Crushes Cosmic Records Across 10 Billion Years
Astronomers have detected the most distant fast radio burst ever recorded. Designated FRB 20240304B, the millisecond-long signal traveled across approximately 80% of cosmic history before reaching Earth.
It originated from a young, metal-poor galaxy when the universe was only about 3 billion years old. That milestone more than doubles the previous distance record for such emissions.
Tracking the Millisecond Flash with MeerKAT and NASA’s James Webb Space Telescope
The discovery began when researchers utilizing the MeerKAT radio telescope in South Africa and the MeerTRAP project captured the flash. Because fast radio bursts are invisible to the human eye and occur at radio wavelengths, pinpointing their exact origin requires high-resolution follow-up observations.
Astronomers subsequently turned to NASA’s James Webb Space Telescope, employing its Near-Infrared Camera to identify the host galaxy. Data gathered by the telescope revealed that the host galaxy existed during the peak of cosmic star formation, a period often referred to as cosmic noon.
The signal registered a dispersion measure of approximately 2,400 units. This indicated that the radio waves traversed a vast expanse of space.
A Compact Galaxy Defies Leading Merger Theories
Most previously cataloged fast radio bursts have been found in massive star-forming galaxies. However, the host galaxy of FRB 20240304B defied these expectations.
It was 1,000 times less massive than anticipated, classifying it as a small galaxy undergoing rapid star formation with very low metal content.
According to findings, this distinct environment provides crucial clues about the progenitors of these energetic events. The characteristics of the host galaxy suggest that the burst was likely produced by a young magnetar—a type of neutron star possessing an exceptionally powerful magnetic field born from a supernova—rather than through the merger of older neutron stars.
Mapping Invisible Matter Across Intervening Cosmic Structures
Beyond identifying the source of the blast, researchers are utilizing the signal to measure the distribution of matter across the universe. Because fast radio bursts interact with the particles they encounter along their trajectory, they act as a natural line-of-sight counter for atoms that cannot be detected by standard optical telescopes.
Analysis of the signal’s path revealed the imprints of multiple intervening cosmic structures. These included a previously unknown galaxy cluster located at a redshift of 0.3, roughly 3.5 billion light-years from Earth, as well as the nearby Virgo Cluster, which is located about 54 million light-years from Earth.
Astronomers intend to leverage these distant pulses to map invisible matter and trace how galaxies and their stellar populations evolved throughout cosmic history.
