A transient radio source removed from the earth gives up puzzles: For a few hours, it radiates around 30 to 60 seconds for a few hours, and then silent for a long time. The group around Natasha Hurley-Walker from the Australian Curtin University and the International Center for Radio Astronomy Research Icrar suspects that the radio source is a neutron star with an extremely strong magnetic field. Even a strongly magnetized white dwarf cannot be ruled out, as the team in "Nature" reported.
The unusual radio source GLEAM-X J162759.5-523504.3 was discovered in the constellation Norma with the Murchison Widefield Array (MWA) in Australia, a system of radio telescope antennas used to monitor the entire sky accessible there. There, PhD student Tyrone O'Doherty noticed the radio source when he tried out a new evaluation program he had developed.
Transient radio sources are nothing unusual in themselves, but they either last for several weeks or months like supernova explosions or are extremely short like the radio flashes of a pulsar. But a source that is active for about a minute, then goes silent again and lights up again was previously unknown.
Repeating transient animation from ICRAR on Vimeo.
The source was unusually bright and its radiation was highly polarized at 88 percent, meaning the radio waves propagated along a preferred plane of oscillation. This indicates a very strong magnetic field at the source.
"This was completely unexpected," Hurley-Walker said in a press release. "It was kind of scary for an astronomer, because there's nothing in the sky that does something like that.«
The object could therefore be a theoretically predicted "Magnetar with ultra -long period", a slowly rotating neutron star. However, it shines much brighter than in the predictions, in an even unknown way the compact star residue converts magnetic energy very efficiently into radio waves. The group around Hurley Walker is currently hoping for a reappearance of the object in the sky in order to be able to examine it even more in more detail.
