To detect the brightest-ever pulsar, ASKAP radio telescope donned a pair of “sunglasses.”

_{Australian Square Kilometre Array Pathfinder radio telescope array credit: CSIRO}

An worldwide study team led by experts from Australia’s national science agency, CSIRO, has discovered the brightest extragalactic pulsar known to date, and it may perhaps be the most brilliant ever discovered.

Pulsars, discovered in 1967, are remains of huge stars that may have uses in fields such as random number generation and satellite guiding systems.

The study team utilised the CSIRO-owned and operated ASKAP radio telescope to test a novel strategy for locating pulsars. They discovered a never-before-seen pulsar that is ten times brighter than any other observed outside our galaxy by employing an astronomical version of “sunglasses” to collect polarised light.

Yuanming Wang is a CSIRO researcher and a Ph.D. candidate at the University of Sydney. She is the primary author on the research, which was published in The Astrophysical Journal.

“This was a very remarkable surprise. I had not anticipated discovering a new pulsar, much less the brightest. However, with the modern telescopes available to us, such as ASKAP and its sunglasses, it is indeed achievable “As Ms. Wang stated.

Professor Tara Murphy of the University of Sydney’s Sydney Institute for Astronomy leads the team that discovered the initial signs of this odd pulsar in the ASKAP data and verified its presence using the MeerKAT radio telescope operated by the South African Radio Astronomy Observatory.

“This method should result in the discovery of other pulsars. This is the first time we have been able to conduct a systematic and regular search for a pulsar’s polarisation. Due to its peculiar features, despite its brightness, this pulsar was overlooked in prior research “Prof. Murphy stated.

Professor Elaine Sadler, Chief Scientist of the CSIRO’s Australia Telescope National Facility, which comprises ASKAP and two additional telescopes utilised in the study, commented on how fantastic it is that the first pulsar discovered using this approach is an extreme one.

“This demonstrates the incredible things we can anticipate from our telescopes and researchers as they continue to discover novel solutions to address some of our most pressing problems. From ATCA to ASKAP, the Australia National Telescope Facility has continued to give extraordinary access to the cosmos “Prof. Sadler said.

A pulsar is a neutron star that rotates quickly and releases two beams of polarised radio waves. As the beams flash through space, they leave a unique trace of time and polarisation.

Traditional pulsar detection methods hunt for this flashing in telescope data but may miss ones that are too rapid or too slow. Instead of scanning for polarised light, pulsars outside the conventional time range can be discovered.

Previously, the radio data’s bright point was misinterpreted as a faraway galaxy.

Further information: Yuanming Wang et al, Discovery of PSR J0523-7125 as a Circularly Polarized Variable Radio Source in the Large Magellanic Cloud, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac61dc

Journal information: Astrophysical Journal

Source: CSIRO