A Repeated Fast Radio Burst is Coming from Within Our Galaxy, Here's Why
File image of Milky way.
Space research mostly involves long intervals of nothing as space-events can be unique and once-in-a-while. However, an object that was caught emitting fast radio bursts in the Milky Way Galaxy is now repeating.
SGR 1935+2154 was first discovered in 2007 when its radio signals confused researchers. These were very powerful bursts of radio-frequency energy. They aren’t long-lasting and dissipate after a few milliseconds. Now, two more powerful radio signals have been observed, similar to those from extragalactic sources.
These bursts are not all at the same strength, suggesting there’s probably more than one process inside the magnetars which can produce these bursts. Previously, fast radio bursts (FRBs) have been detected only from outside the Milky Way. They are also likely to flare only once and without warning, making them difficult to trace. Then, on April 28 thus year, a dead but highly magnetised star in our galaxy was emitting powerful radio waves for a millisecond. Now, it has finally been named as FRB 200428 and confirmed as an official FRB.
Later, on May 24, Westerbork Synthesis Radio Telescope in the Netherlands recorded not one but two radio bursts from the magnetar with high intensity. A telescope in China caught a much fainter burst. It is unclear why the bursts have ranged so much in their intensities.
“Assuming that a single emission mechanism is responsible for all reported radio bursts from SGR 1935+2154, it has to be of such a type that the burst rate is close to independent of the amount of energy emitted across more than seven orders of magnitude,” the researchers in the study said. The study has been published in Nature Astronomy.
Coming back to the magnetars, they are kind of a dead neutron star. They can add to the intense magnetic field of a normal neutron star. Though not much is known about their origins. However, it is known there are periods of disruption and activity in their existence. Their gravity pulls the star inward while the magnetic field pulls outward, thus distorting the shape of the star. Through these forces, instabilities are produced like quakes and flares, observable in high-energy X-rays and gamma radiation.
One of the FRBs from the SGR 1935+2154 was accompanied by an X-ray flare. The other two weren’t. This concludes the two don’t depend on each other and can happen independently. In any case, there isn’t enough data to say for sure why these FRBs are repeating.
Lastly, on October 8, another three radio bursts emerged from it. Researchers hope for more and hope to conclude a pattern or a system out of these FRBs.