Fast Radio Burst FRB 20220610A, the most powerful radio burst ever observed was detected on 10 June 2022. It had originated from a source that existed 8.5 billion years ago when the universe was just 5 billion years old which makes the source farthest known for an FRB. The source was thought to be either a single, irregular galaxy or a group of three distant galaxies. However, study of images captured by Hubble telescope on follow-up after its discovery reveals seven sources, one of which was identified as the host galaxy. The host galaxy was also determined to be a star-forming galaxy. The study identified the system as a compact galaxy group whose members showed signs of interaction among themselves. Galaxies in compact groups are uncommon, hence the finding of FRB 20220610A originating in such an environment presents a novel origin of FRBs.
Fast radio bursts (FRBs), also called Lorimer Bursts are extremely energetic flash of radio waves. They are very brief lasting for few milliseconds. Since its first discovery in 2007 by Duncan Lorimer, about 1000 FRBs have been detected.
The fast radio burst FRB 20220610A was detected on 10 June 2022. Four times more energetic than closer FRBs, it was the most powerful fast radio burst (FRB) ever observed. It had originated from its source that existed 8.5 billion years ago when the universe was only 5 billion years old. The FRB had travelled for 8.5 billion years to reach Hubble. The source was the farthest known so far for any FRB and thought to be either a single, irregular galaxy or a group of three distant galaxies.
However, sharp images captured by the Hubble telescope on follow-up after its discovery has revealed that the source of FRB 20220610A was not ‘one monolithic galaxy’. Usually, FRBs originate from isolated galaxies. Instead, this fast radio burst had originated from an interacting system of at least seven galaxies in proximity on the path of merging. This development broadens the list of possible sources of FRBs.
The origin and mechanism of formation FBR is not clearly understood. Nevertheless, it is agreed that highly compact bodies like neutron star or black hole are involved in generation of powerful radio blasts. Extreme physics phenomena such as collision of black hole or neutron star, starquakes when the crust of a neutron star undergoes sudden adjustments, sudden snaping of tangled magnetic fields of most intensely magnetic type of neutron stars (a process akin to formation of solar flares but at much higher scale), periodic interaction of magnetospheres of a pair of orbiting neutron stars are some of possible mechanisms of formation of Fast radio bursts (FRBs).
The science of origin and mechanism of formation of fast radio bursts (FRBs) is largely incomplete however the latest study fills some knowledge gap.
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References:
- NASA Hubble Mission Team. News – Hubble Finds Weird Home of Farthest Fast Radio Burst. Posted on 09 January 2024. Available at https://science.nasa.gov/missions/hubble/hubble-finds-weird-home-of-farthest-fast-radio-burst/
- Gordon A.C., et al 2023. A Fast Radio Burst in a Compact Galaxy Group at z~1. Preprint arXiv:2311.10815v1. Submitted on 17 Nov 2023. DOI: https://doi.org/10.48550/arXiv.2311.10815
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