Astronomers discover record burst of energy coming from deep space
A team of astronomers from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR) has detected a record-breaking energy burst from deep space. The source of this intense energy pulse, dubbed GLEAM-X J0704-37, is a binary system consisting of a small red dwarf star and a white dwarf, the remnant of a dead star. They made the discovery using archival low-frequency data from the Murchison Widefield Array (MWA).
GLEAM-X J0704-37: A unique long-period radio transient
The energy pulse, GLEAM-X J0704-37, is a one-of-a-kind long-period radio transient that erupts every three hours and lasts for 30-60 seconds. This makes it the longest-lasting case of such a phenomenon ever recorded. Since their first detection in 2006, these transients have baffled astronomers with their ability to generate radio waves. The latest discovery could shed light on the source of these energy bursts.
Challenges in studying long-period radio transients
The study of long-period radio transients has been difficult because they are located in densely populated regions of the Milky Way. This makes it hard to figure out what is producing these bursts of radio waves. Natasha Hurley-Walker, a member of the discovery team and researcher at Curtin University, said an optical image is required to understand these transients but there are often too many stars blocking the view.
GLEAM-X J0704-37's origin traced to specific star system
The discovery of GLEAM-X J0704-37 was a stroke of luck since it came from a less crowded region of the Milky Way, around 5,000 light-years away. "Our new discovery lies far off the galactic plane, so there are only a handful of stars nearby, and we're now certain one-star system, in particular, is generating the radio waves," Hurley-Walker said. The team traced the origin of this peculiar long-period radio transient to one particular star system using South Africa's MeerKAT telescope.
Binary system of red and white dwarf powers radio emission
The researchers found one of the stars in the GLEAM-X J0704-37 emitting system to be a low-mass red dwarf star or M-dwarf. However, an M-dwarf alone couldn't generate the observed energy levels. Additional analysis indicated that this red dwarf is part of a binary system with another object, possibly a white dwarf. "Together, they power radio emission," Hurley-Walker said, explaining the source of these powerful energy bursts.
Magnetic fields and energy blasts: A new theory
The research team suggested that strong magnetic fields in this binary system could be causing the periodic energy blasts. These are similar to those seen from rapidly spinning neutron stars or pulsars. The unique location of the GLEAM-X J0704-37 emitting system helped researchers rule out a highly magnetic neutron star, or magnetar, as its source. The team is now working on confirming this binary system's nature and explaining how it launched GLEAM-X J0704-37.
