SYDNEY, Nov. 27 (Xinhua) -- Astronomers in Western Australia (WA) said they have made a discovery that could explain a rare astrophysical event known as long-period radio transients.
In a new study, a team from the International Center for Radio Astronomy Research (ICRAR) in WA discovered the longest-period radio transient ever detected, said a news release on ICRAR's website on Tuesday.
Long-period radio transients are a class of rare astrophysical events that emit pulsations of very bright radio energy. How they generate radio waves has been an ongoing mystery for astronomers.
The pulses typically last tens of seconds and occur in intervals ranging from minutes to an hour. The new pulse, given the name GLEAM-X J0704-37, occurs every three hours and lasts 30-60 seconds, making it the longest-known such phenomenon.
It was discovered in deep space from low-frequency data gathered by the Murchison Widefield Array (MWA) radio telescope in outback WA.
While every other known transient was found in our own galaxy surrounded by stars, making it difficult to determine what is generating the radio waves, GLEAM-X J0704-37 was found on the outskirts of the galaxy in a relatively empty region of space 5,000 light years away.
Researchers Natasha Hurley-Walker and Csanad Horvath from the Curtin University node of the ICRAR were able to pinpoint the source of the radio waves to one specific low-mass star by using telescopes in South Africa and Chile.
Hurley-Walker said the low-mass star, also called M dwarfs, could not have generated the amount of energy detected alone.
"Our data suggests that it is in a binary with another object, which is likely to be a white dwarf, the stellar core of a dying star. Together, they power radio emission," she said.
Further analysis of archival data from the MWA revealed that GLEAM-X J0704-3 has been active for at least 10 years since the telescope started observing.
The team is now working on follow-up observations to conclusively explain long-period radio transients. ■
