The cosmic body is distinctive when compared with other discoveries of radio bursts in recent years, according to new research.
Fast radio bursts, or FRBs, are millisecond-long bursts of radio waves in space. Single radio bursts are emitted once and are not repeated. But it is known that repeating fast radio bursts send out short, energetic radio waves many times.
Astronomers have been able to trace some of the radio bursts back to their home galaxies, but they haven’t yet determined the true cause of these bursts. Learning more about the origin of these bright and intense radio emissions can help scientists understand their causes.
Astronomers discovered the object, named FRB 190520, when it released a burst of radio waves on May 20, 2019. The researchers used the Five Hundred-Meter Aperture Spherical Radio Telescope, or FAST, in China, and detected the explosion in the telescope in November 2019. When they made follow-up observations, Astronomers noticed something unusual – the object was emitting repeated bursts of radio waves.
In 2020, the team used the National Science Foundation’s Karl G. Jansky Very Large Array Telescope, or VLA, to determine the origin of the explosion before focusing on it using the Subaru Telescope in Hawaii. Subaru’s observations in visible light showed that the explosion came from the fringes of a distant dwarf galaxy.
Two of the same type
VLA observations also revealed that celestial bodies The body continuously released weaker radio waves between repeated bursts. This is very similar to the well-known repeating fast radio burst: FRB 121102, discovered in 2016.
“We now actually need to explain this double puzzle and why FRBs and persistent radio sources are sometimes found together,” said study co-author Casey Law, a radio astronomer at Caltech. “Is it common when FRBs are small? Or perhaps the object making the bursts is a supermassive black hole chaotically devouring a neighboring star? Theorists have so much detail to work with now, and the scope for interpretation is shrinking.”
Currently, less than 5% of the hundreds of identified FRBs are known to be repeated and only a few of them are regularly active.
Only FRB 190520 is continuously active, meaning it has not been “turned off” since its discovery, said study author Di Li, chief scientist with the Radio Department of China’s National Astronomical Observatories and the Rapid Operations Center. Meanwhile, Lee said that FRB 121102, “the first known major repeater, could be out of business for several months.”
The latest discoveries raise more questions because astronomers are now wondering if there are two types of fast radio bursts.
“Are those that repeat different from those that don’t? And what about continuous radio broadcasts – is this common?” Study co-author Kshitij Aggarwal, who participated in the study as a doctoral student at West Virginia University, said in a statement.
It is possible that there are different mechanisms that cause the radio impulses, or that everything that results in them behaves differently during different stages of development.
Previously, scientists assumed that fast radio bursts result from the dense remnants left by a supernova, called neutron stars, or neutron stars with incredibly strong magnetic fields called magnetars.
FRB 190520 considered as a possible ‘newborn’ organism Lau said because he was located in a dense environment. This environment may be caused by a substance released by a supernova, which, in the creation of a neutron star. Because this material is dispersed over time, fluxes from FRB 190520 may decrease with age.
Going forward, Li wants to detect more rapid radio bursts.
“A coherent picture of the origin and evolution of FRBs is likely to emerge in just a few years,” Lee said.
Lau is excited about the implications of a new class of radio wave sources.
“For decades, astronomers have believed that there are two basic types of radio sources that we can see in other galaxies: the accumulation of supermassive black holes and the activity of star formation,” Lu said. “Now we’re saying it can’t be either a classification/or a classification anymore! There’s a new kid in town and we should think about that when studying groups of radio sources in the universe.”