A team of scientists tracking radio waves in the cosmos has found something strange that produces a massive burst of energy three times per hour, and it’s unlike anything astronomers have ever seen. The odd object, which is spinning around in space, emits a beam of radiation that crosses our line of sight and is one of the brightest radio emitters in the sky for one minute out of every twenty.
A team of scientists studying radio waves in the Universe has uncovered something unique that emits a massive burst of energy three times per hour and is unlike anything astronomers have seen previously.
It might be a neutron star or a white dwarf, which are star cores that have collapsed, with an extremely intense magnetic field, according to the researchers.
The odd object, which is spinning around in space, emits a beam of radiation that crosses our line of sight and is one of the brightest radio emitters in the sky for one minute out of every twenty.
The team that discovered the finding was headed by astronomer Dr Natasha Hurley-Walker of the Curtin University node of the International Centre for Radio Astronomy Research.
“This item appeared and vanished over the course of a few hours during our observations,” she said.
“That was a huge surprise. For an astronomer, that seemed a little strange since there’s nothing else in the sky that can accomplish that.
“It’s also fairly near to us, being just 4000 lightyears distant. It’s right here in our galaxy.”
Tyrone O’Doherty, a Curtin University Honours student, spotted the object in outback Western Australia using the Murchison Widefield Array (MWA) telescope and a novel approach he devised.
Mr O’Doherty, who is currently doing a PhD at Curtin, said, “It’s amazing that the source I detected last year has turned out to be such a distinctive thing.”
“With its large field of vision and high sensitivity, the MWA is ideal for studying the whole sky and discovering the unexpected.”
Astronomers are familiar with objects that switch on and off in the Universe, which they refer to as ‘transients.’
“When investigating transients, you’re seeing the death of a giant star or the activity of the debris it leaves behind,” explained ICRAR-Curtin astronomer and co-author Dr Gemma Anderson.
‘Slow transients,’ like supernovae, may occur for a few days and then fade away after a few months.
Fast transients, such as pulsars, are neutron stars that flash on and off in milliseconds or seconds.
Dr. Anderson, on the other hand, thought discovering anything that switched on for a minute was strange.
She said the enigmatic object was extraordinarily brilliant and tiny in comparison to the Sun, radiating highly polarized radio waves, implying it had a very strong magnetic field.
The findings are consistent with a projected astrophysical phenomenon known as a ‘ultra-long period magnetar,’ according to Dr Hurley-Walker.
She said, “It’s a form of slowly rotating neutron star that has been theoretically predicted to occur.”
“We didn’t anticipate them to be that brilliant, therefore no one expected to immediately detect one like this.
“It converts magnetic energy to radio waves much more efficiently than anything we’ve seen previously,” says the researcher.
Walker is now using the MWA to keep an eye on the item to see if it turns back on.
“If it does,” she continued, “there are telescopes all around the Southern Hemisphere and even in space that can aim right at it.”
Dr. Hurley-Walker intends to investigate the MWA’s huge archives for more of these odd artefacts.
“More detections will tell astronomers whether this was a rare one-off occurrence or a massive new population we hadn’t observed previously,” she said.
The telescope is a predecessor device for the Square Kilometre Array, a worldwide endeavor to construct the world’s biggest radio telescopes in Western Australia and South Africa, according to MWA Director Professor Steven Tingay.
“The fact that we have been able to gather and preserve all of the data the MWA generates for nearly a decade at the Pawsey Research Supercomputing Centre has been critical to locating this item and researching its precise features. It’s really rare in astronomy to be able to go back over such a large dataset when you identify an item “he said
“The MWA and the SKA will undoubtedly unearth many more treasures in the future years.”
The Murchison Widefield Array is housed in Western Australia’s Murchison Radio-astronomy Observatory. The observatory is run by the CSIRO, Australia’s national research organization, and was built with the assistance of the Australian and Western Australian governments. The Wajarri Yamatji are the traditional proprietors of the observatory site, which we recognise.
The MWA observations were stored and processed at the Pawsey Supercomputing Research Centre in Perth, a Tier 1 publically financed national supercomputing facility.
The MWA includes the Shanghai Astronomical Observatory (SHAO). The Chinese Ministry of Science and Technology and the Chinese Academy of Sciences supported SKA Regional Centre Prototype, which is hosted by SHAO and contributed to processing the MWA observations utilized in this study.