The origin of a fast radio burst from space has been narrowed down by astronomers with ‘an amazing range of scales involved’.
Researches from Massachusetts Institute of Technology have published a new study which reveals the source of a specific radio burst that has been detected from a galaxy roughly 200 million light-years away.
Fast radio bursts
Fast radio bursts (FRBs) were first discovered by scientists in 2007, Science Alert reports.
The bursts of radio emission lasting just milliseconds are extremely powerful and only burst once – which has made them difficult to study.
However, in 2022, a team of astronomers honed in on a radio burst named FRB 20221022A, which was detected from a galaxy roughly 200 million light-years away – with the signal lasting about two milliseconds.
And scientists have since been able to pinpoint the source of the radio waves, a new study published in Nature – titled Magnetospheric origin of a fast radio burst constrained using scintillation – weighing up two options in particular.
The radio burst’s origin
The team studied something called scintillation in a bid to trace FRB 20221022A back to its source.
Scintillation – also known as twinkling – is the ‘generic term for rapid variations in apparent position, brightness, or color of a distant luminous object viewed through the atmosphere’, NASA’s Thesaurus explains, and the study found the changes in the FRB’s brightness means the radio burst occurred close to its source.
Another study – titled A pulsar-like polarization angle swing from a nearby fast radio burst – analyzed the shape of the radio waves and found it showed ‘a notable approximately 130° PA rotation over its about 2.5 ms burst duration, resembling the characteristic S-shaped evolution seen in many pulsars and some radio magnetars’, which supported the theory that the radio wave is from a place with a strong magnetic field and somewhere which is rotating too.
In the new study, the team also confirmed some of the scintillation was being caused by gas within the FRB’s host galaxy and they were subsequently able to figure out an area small as 10,000 kilometers wide where the burst originated from.
Given the pattern’s echoes with previous observations of highly magnetized, rotating neutron stars, scientists ultimately concluded FRB 20221022A had likely exploded from close to a rotating neutron star, bursting within its magnetosphere.
What it means
Massachusetts Institute of Technology (MIT) physicist Kiyoshi Masui said: “Zooming in to a 10,000-kilometer region, from a distance of 200 million light years, is like being able to measure the width of a DNA helix, which is about two nanometers wide, on the surface of the moon.
“There’s an amazing range of scales involved.”
While noting atoms ‘can’t exist’ around ‘highly magnetic neutron stars, also known as magnetars’ given they’d ‘just get torn apart by the magnetic fields,’ Masui explains the ‘exciting thing here is’ the study found ‘that the energy stored in those magnetic fields, close to the source, is twisting and reconfiguring such that it can be released as radio waves that we can see halfway across the Universe’.
