Fast radio bursts (FRBs) are one of the most mysterious phenomena in the universe. They are extremely powerful flashes of radio waves that last only a fraction of a second, but can release as much energy as the sun in a year. They also form laser-like beams, unlike the more chaotic universe**.
For more than a decade, scientists have been puzzled by the origin and nature of these elusive signals. So far, most of the detected FRBs have come from distant galaxies, so it is difficult to determine their exactly** and why. However, in 2020, astronomers detected the first FRB from our Milky Way and tracked it down to a dead star called a magnetar.
Magnetars are the remnants of massive stars in supernovae. It is very dense, about 12 miles (20 km) in diameter, and has a strong magnetic field. It also spins quickly, about 32 times, sometimes experiencing a sudden change in its rate of rotation, known as a burr. This ** gives a brief account of the birth of magnetars.
In October 2022, a magnetar named SGR 1935+2154 sent another FRB, which was captured by two NASA X-ray telescopes: NICER (Neutron Star Internal Composition Detector) on the International Space Station and NuStar (Nuclear Spectroscopic Telescope Array) in low Earth orbit. These telescopes observed magnetars for hours before and after the FRB, providing a unique perspective of what is happening on and around the surface of the magnetar.
The results of the study, published in the journal Nature, show that when a magnetar suddenly accelerates and then decelerates, FRB occurs between two burrs. The researchers were surprised that the magnetar slowed down to a slower speed than before the failure, or about 100 times faster than the magnetar, within nine hours.
Normally, when a failure occurs, it takes weeks or months for a magnetar to return to its normal speed," said Chin-Ping Hu, an astrophysicist at the National Changhua University of Education in Taiwan and lead author of the study. "It is clear that these objects are occurring on much shorter time scales than we previously thought, which may be related to the speed at which radio bursts are generated.
Observations of FRB from SGR 1935+2154 are a rare opportunity to study these mysterious events in detail. It also shows how NASA's telescopes work together to track ephemeral events in the universe.
However, the mystery of the FRB remains to be solved. Scientists must understand how magnetars produce these powerful radio flashes and whether all FRBs come from magnetars or other**. They must also understand what causes magnetar failures and how they affect magnetic fields and emissions.
One possible clue is that FRB occurs during intense X-ray and gamma-ray activity on magnetars, which may indicate changes in their internal structure or magnetic field.
In principle, all X-ray bursts that occurred before this failure had enough energy to produce fast radio bursts, but this is not the case," said Zorawar Wadiasingh, co-author of the study, who is a research scientist at the University of Maryland, College Park, and NASA's Goddard Space Flight Center. "So something seems to have changed during the economic slowdown, creating the right conditions.
Another factor that may play a role is the interaction between the solid crust and the superfluid interior of the magnetar. The high density of a magnetar crushes the material inside into a state where it can flow frictionlessly, like water shaking inside a rotating fish tank. Sometimes, the earth's crust and superfluid are out of sync, and the superfluid transfers energy to the earth's crust, causing the crust to crack or deform.
*In the author's opinion, this could lead to a malfunction of the FRB. If the initial failure creates a crack in the Earth's crust, it may release some material from the inside of the magnetar into space, like a volcanic eruption. This will reduce the mass and angular momentum of the magnetar, making it slow down faster.
However, having only observed one of these events in real time, the team was still unable to determine which factors (or others, such as the strong magnetic field of the magnetar) could have contributed to the production of FRB. Some may not be connected to the burst at all.
There is no doubt that we have observed something important for our understanding of fast radio bursts," said George Younes, a researcher at Goddard and a member of the NICER science team that specializes in magnetars. "But I think we still need more data to finish this mystery.
The discovery of the FRB of SGR 1935+2154 opened a new window into the physics of these cosmic puzzles. It also shows the potential of NASA's X-ray telescopes to capture and study these fleeting events.
The researchers hope to continue monitoring magnetars with Niker, Nustar, and other telescopes to look for more clues about their behavior and connection to FRB. They also want to probe more FRBs from other ** and compare their characteristics and **.
By combining observations from different wavelengths and different instruments, scientists hope to uncover the secrets of these mysterious radio flashes and learn more about the extreme environment in which they were born.
Publish a collection of dragon cards to share millions of cash