The recurring source of fast radio flashes detected last year has already produced 1,863 flashes in 82 hours for a total observation time of 91 hours.

This hyperactive behavior has allowed scientists to characterize not only the galaxy in which the source is located and its distance from us, but also what the source represents.

The object, named FRB 20201124A, was detected using a five-hundred-meter aperture spherical radio telescope (FAST) in China and is described in a new paper led by astronomer Heng Xu of Peking University in China.

So far, most evidence points to a magnetar – a neutron star with unusually strong magnetic fields – as the source of such FRB emissions.

If FRB 20201124A does indeed belong to one of these “wild cosmic beasts,” it looks like an unusual specimen.

“These observations brought us back to the drawing board,” says astrophysicist Bing Zhang of the University of Nevada at Las Vegas. – It’s clear that FRBs are more mysterious than we imagined. Additional multi-wavelength observing campaigns are needed to further unravel the nature of these objects.”

Fast radio bursts have been a mystery to astronomers since they were first detected 15 years ago in archived data dating back to 2001: a burst of incredibly powerful radio emission lasting only a blink of an eye. Since then, many similar bursts have been detected: millisecond bursts of radio waves, ejecting as much energy as 500 million suns in that moment.

Most of the recorded eruptions erupted only once, making them difficult to study (let alone understand). Only a few were found to be repetitive, which helped scientists at least track them to host galaxies.

Then, in 2020, there was a breakthrough. For the first time, a fast radio burst was detected in the Milky Way, prompting astrophysicists to trace the phenomenon to magnetar activity.

The latest FRB extraordinaire is another example of such a rare repeater. In less than two months of observations, FRB 20201124A provided astronomers with the largest sample of polarized fast radio burst data than any other FRB source.

Polarization refers to the orientation of light waves in three-dimensional space. By studying how much this orientation has changed since the light left its source, scientists can understand the medium through which it passed. For example, strong polarization suggests a strong magnetic environment.

Based on the large amount of data provided by FRB 20201124A, astronomers were able to conclude that the source was a magnetar.

But there was something strange about this phenomenon. The way the polarization changed over time suggested that the magnetic field strength and particle density around the magnetar fluctuated.

“Such an environment is not directly expected for an isolated magnetar. Something else might be in the vicinity of the FRB engine, perhaps a binary companion,” Zhang explains.

The data suggest that this companion could be a hot blue Ve-type star, which are often found in companion neutron stars. Evidence for this was presented in a separate paper led by astronomer Fain Wang of Nanjing University in China.

But FRB 20201124A was discovered in a galaxy very similar to the Milky Way. There is not much star formation going on here, so there should not be a star boom near the unusual FRB.

However, FRB 20201124A is not the only FRB source found in a galaxy relatively devoid of star formation. The growing number of bursts suggests that there is some important piece of information that scientists are missing.