Astronomers find new type of stellar object that challenges understanding of neutron star physics

A world group led by astronomers from the Curtin College node of the Worldwide Heart for Radio Astronomy Analysis (ICRAR) has found a brand new kind of stellar object that challenges our understanding of the physics of neutron stars.

The article might be an ultra-long interval magnetar, a uncommon kind of star with extraordinarily sturdy magnetic fields that may produce highly effective bursts of vitality.

Till just lately, all identified magnetars launched vitality at intervals starting from just a few seconds to a couple minutes. The newly found object emits radio waves each 22 minutes, making it the longest interval magnetar ever detected. The analysis was printed within the journal Nature.

Astronomers found the item utilizing the Murchison Widefield Array (MWA), a radio telescope on Wajarri Yamaji Nation in outback Western Australia. Lead writer Dr. Natasha Hurley-Walker mentioned the magnetar, named GPM J1839−10, is 15,000 light-years away from Earth within the Scutum constellation.

“This exceptional object challenges our understanding of neutron stars and magnetars, that are among the most unique and excessive objects within the universe,” she mentioned.

The stellar object is just the second of its variety ever detected after the primary was found by Curtin College undergraduate analysis scholar Tyrone O’Doherty.

Initially, scientists couldn’t clarify what they’d discovered. They printed a paper in Nature in January 2022 describing an enigmatic transient object that might intermittently seem and disappear, emitting highly effective beams of vitality thrice per hour.

Dr. Hurley-Walker—O’Doherty’s honors supervisor—mentioned the primary object took us unexpectedly.

“We have been stumped,” she mentioned. “So we began looking for comparable objects to seek out out if it was an remoted occasion or simply the tip of the iceberg.”

Between July and September 2022, the group scanned the skies utilizing the MWA telescope. They quickly discovered what they have been in search of in GPM J1839−10. It emits bursts of vitality that last as long as 5 minutes—5 instances longer than the primary object.

Different telescopes adopted as much as verify the invention and study extra concerning the object’s distinctive traits.

These included three CSIRO radio telescopes in Australia, the MeerKAT radio telescope in South Africa, the Grantecan (GTC) 10m telescope, and the XMM-Newton space telescope.

Armed with GPM J1839−10’s celestial coordinates and traits, the group additionally started looking the observational archives of the world’s premier radio telescopes.

“It confirmed up in observations by the Large Metrewave Radio Telescope (GMRT) in India, and the Very Massive Array (VLA) within the U.S. had observations relationship way back to 1988,” she mentioned.

“That was fairly an unimaginable second for me. I used to be 5 years previous when our telescopes first recorded pulses from this object, however nobody observed it, and it stayed hidden within the information for 33 years.

“They missed it as a result of they hadn’t anticipated to seek out something prefer it.”

Not all magnetars produce radio waves. Some exist under the “demise line,” a vital threshold the place a star’s magnetic subject turns into too weak to generate high-energy emissions.

“The article we have found is spinning approach too slowly to supply radio waves—it is under the demise line,” Dr. Hurley-Walker mentioned.

“Assuming it is a magnetar, it should not be attainable for this object to supply radio waves. However we’re seeing them. And we’re not simply speaking about somewhat blip of radio emission. Each 22 minutes, it emits a five-minute pulse of radio wavelength vitality, and it has been doing that for at the very least 33 years.

“No matter mechanism is behind that is extraordinary.”

The invention has vital implications for our understanding of the physics of neutron stars and the conduct of magnetic fields in excessive environments.

It additionally raises new questions concerning the formation and evolution of magnetars and will make clear the origin of mysterious phenomena equivalent to quick radio bursts.

The analysis group plans to conduct additional observations of the magnetar to study extra about its properties and conduct.

In addition they hope to find extra of those enigmatic objects sooner or later, to find out whether or not they’re certainly ultra-long interval magnetars, or one thing much more phenomenal.

The MWA is a precursor to the world’s largest radio astronomy observatory, the Sq. Kilometer Array, which is underneath development in Australia and South Africa. The MWA celebrates a significant milestone this 12 months because it completes a decade of operations and worldwide scientific discovery.

The Worldwide Heart for Radio Astronomy Analysis (ICRAR) is a joint venture between Curtin College and The College of Western Australia.