Amazing stuff!
"10.6 billion years ago, long before the Earth and Sun had formed, a faraway galaxy released a fast blast of radio waves. These waves traversed the universe and, in 2024, found their way into the giant radio dishes of South Africa’s MeerKAT radio telescope. Scientists have since confirmed the blast, called a fast radio burst (FRB) catalogued as FRB 20240304B, as the oldest and furthest ever detected.
The origin of FRBs are not known, but scientists think they may come from young magnetars, rare types of dense stellar cores with magnetic fields more than a trillion times that on Earth. To determine the FRB’s galactic host, scientists turned to the James Webb Space Telescope ... They found that the new FRB came from a young, rapidly star-forming galaxy, ripe for magnetars to form. ..."
"... The team discovered that the host galaxy of FRB 20240304B was not typical of other galaxies with FRBs. Most FRB galaxies are massive star-forming galaxies, but the galaxy they found was 1,000 times less massive than they expected. ...
The galaxy existed at the height of “cosmic noon” – a period in the history of the universe when star formation was at its peak. The galaxy’s rate of star formation suggested that the majority of its stars may have formed within just 30 million years.
This has important implications for the origin of fast radio bursts.
One theory suggests that FRBs may originate from the merger of two neutron stars. However, the process of orbiting neutron stars gradually approaching closer and closer until they collide is expected to take billions of years. As a result, FRBs would be expected to be associated with older galaxies containing more evolved stellar populations.
A second theory proposes that an FRB can originate from a single, young, highly magnetic neutron star known as a magnetar through a mechanism like starquakes. In that case, once a massive star explodes as a supernova and leaves behind a magnetar, an FRB might occur relatively quickly with no large time delay. As a result, FRBs would also be expected to be found in younger galaxies like the host of FRB 20240304B. ..."
From the abstract:
"Fast radio bursts (FRBs) are millisecond-duration radio transients from extragalactic sources. Their frequency and polarization properties are affected by plasma and magnetic fields along the line of sight to Earth.
We report radio observations of FRB 20240304B and near-infrared follow-up to identify its host galaxy. The host is a low-mass, clumpy, star-forming galaxy at redshift 2.148 ± 0.0013, corresponding to 3 billion years after the Big Bang. This FRB occurred during the peak of cosmic star formation and probes ionized gas over approximately 80% of cosmic history.
The highly scattered burst emission implies that there is a population of FRBs that are undetected by current surveys."
Webb Measures Distance to Farthest Fast Radio Burst, Suggesting Origin (original news release)
A fast radio burst at redshift 2, three billion years after the Big Bang (no public access)
A fast radio burst from the first 3 billion years of the Universe (preprint, open access)
NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) was able to detect the host galaxy of the fast radio burst called FRB 20240304B, whose location is shown by the white cross. They found it is a small dwarf galaxy actively forming stars.
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