An international team of astronomers, utilizing the MeerKAT radio telescope in South Africa and the James Webb Space Telescope (JWST), has successfully detected and localized FRB 20240304B, the most distant Fast Radio Burst (FRB) ever recorded. The discovery, made on March 4, 2024, pushes the frontiers of our understanding of the early universe, pinpointing the FRB's origin to a galaxy with a redshift of 2.148.
This significant redshift places the FRB's source approximately 3 billion years after the Big Bang, a period known as "cosmic noon," which occurred roughly 10 to 11 billion years ago. Cosmic noon was characterized by intense star formation across the universe. By effectively doubling the redshift reach for localized FRBs, this finding provides an unprecedented opportunity to study galaxies during this crucial formative epoch.
The JWST's advanced capabilities were instrumental in identifying the host galaxy of FRB 20240304B. Observations revealed it to be a low-mass, actively star-forming galaxy with an estimated stellar mass of 10 million solar masses and a star formation rate of 0.2 solar masses per year. The analysis of the FRB's dispersion measure, a key indicator of how much the radio signal was stretched and delayed by intervening plasma, further confirmed its extreme distance. The dispersion measure reached approximately 2,330 parsecs per cubic centimeter, serving as a unique marker of the signal's extensive journey through the cosmos.
This discovery is particularly important as it allows scientists to probe the distribution of ionized matter across a substantial portion of the universe's history, estimated at around 80%. Previously, localized FRBs had only offered insights into about half of cosmic time. The ability to study FRBs from such an early epoch provides invaluable data for understanding galaxy formation processes and the distribution of matter in the nascent universe.
The MeerKAT telescope, a precursor to the Square Kilometre Array (SKA), is a powerful instrument comprising 64 dishes. Its capabilities, combined with the sensitivity of the JWST, were crucial for this groundbreaking detection. The MeerKAT+ expansion project is expected to further enhance these observational capacities. This finding underscores the potential of FRBs as cosmic messengers, promising to unlock deeper secrets about the universe's evolution.