Webb Pins Down FRB Host at Redshift 2.148, Backing Magnetar Origin
Updated
Updated · Science@NASA · Oct 8
Webb Pins Down FRB Host at Redshift 2.148, Backing Magnetar Origin
3 articles · Updated · Science@NASA · Oct 8
Summary
Webb confirmed FRB 20240304B came from the most distant fast radio burst host yet measured, fixing the galaxy at redshift 2.148—when the universe was about 3 billion years old.
NIRCam found the faint host after ground telescopes saw nothing at the burst position, and NIRSpec measured its distance precisely enough to verify the record.
The host turned out to be a dwarf galaxy about 1,000 times less massive than expected but still actively forming stars, with much of its stellar population possibly built within 30 million years.
That young, star-forming environment makes a neutron-star merger an unlikely source for this burst and instead strengthens the case for a magnetar formed soon after a supernova.
The burst also traced matter between its source and Earth, revealing signatures from a previously unknown galaxy cluster at redshift 0.3 and the nearby Virgo Cluster.
Could a mysterious radio flash from 10.6 billion years ago finally reveal the universe's hidden matter and unknown galaxy clusters?
What secrets do highly magnetized dead stars hold about the rapid birth of tiny dwarf galaxies near the dawn of time?
If traditional telescopes were completely blind to this ancient cosmic flashlight, what other invisible phenomena are currently passing right through Earth?
FRB 20240304B: Record-Breaking Fast Radio Burst Reveals Secrets of the Universe’s First 3 Billion Years
Overview
On March 4, 2024, South Africa's MeerKAT radio telescope detected FRB 20240304B, a fast radio burst whose highly dispersed signal revealed it had traveled an immense distance through cosmic plasma. Ground-based telescopes failed to spot its faint host galaxy, prompting astronomers to use NASA’s James Webb Space Telescope, which successfully identified the galaxy and measured a record-breaking redshift of 2.148. This doubled the previous distance record for localized FRBs, allowing scientists to probe most of the universe’s history. The discovery also showed that such bursts can originate from small, rapidly star-forming galaxies during the universe’s peak star-formation era.