Mysteries of a Pulsating Star Solved, revealing a Cosmic Couple
For a decade, astronomers have observed a puzzling phenomenon in the outer reaches of our galaxy. Every three hours, a bright pulse of radio energy, lasting for about a minute, emanated from a seemingly nonexistent source. Now, researchers have not only identified the source, but also solved the mystery of its energetic outbursts.
Tracing the Source of the Signal
The cosmic beacon, dubbed GLEAM-X J0704-37, was first spotted while researchers from Curtin University were analyzing data from the Murchison Widefield Array (MWA), a radio telescope located in Western Australia. This unusual signal is the longest-period radio transient ever recorded, with most similar signals occurring over much shorter periods, ranging from tens to thousands of seconds.
“The long-period transients are very exciting, and for astronomers to understand what they are, we need an optical image,” Dr. Natasha Hurley-Walker, an associate professor at Curtin and lead author of a study published in
The Astrophysical Journal Letters, said. “However, when you look toward them, there are so many stars lying in the way that it’s like 2001: A Space Odyssey. ‘My god, it’s full of stars!’.”
Finding the Culprit Amidst the Stars
Luckily, GLEAM-X J0704-37 was located in a relatively clear patch of the Milky Way, about 5,000 light-years away in the Puppis constellation. “Our new discovery lies far off the Galactic Plane, so there are only a handful of stars nearby,” Dr. Hurley-Walker added.
Using the MeerKAT telescope in South Africa, the research team pinpointed the signal’s origin to a specific star. Further observations with the SOAR Telescope in Chile confirmed that the star was a red dwarf, a type of small and faint star.
“An M dwarf alone couldn’t generate the amount of energy we’re seeing,” Hurley-Walker explained. “The M dwarfs are low-mass stars that have a mere fraction of the Sun’s mass and luminosity. They constitute 70 per cent of the stars in the Milky Way, but not one of them is visible to the naked eye.”
A Cosmic Duet
The data revealed a fascinating twist: the red dwarf was not alone. It appears to be part of a binary system with a white dwarf, the collapsed remnant of a star that has exhausted its nuclear fuel and shed its outer layers.
Together, the red dwarf and the white dwarf appear to create a celestial “energy orchestra”.
“Together, they power the radio emission,” Hurley-Walker said.
Although archival data suggests that GLEAM-X J0704-37 has been active for at least a decade, it is potentially older and may have been pulsing for much longer. The discovery team is eager to perform further observations of this intriguing celestial pair and explore archival data for other long-period radio transients. “There could be a lot more weird cosmic sources pulsing with energy across the universe” said Hurley-Walker.
How do the regular pulsation patterns observed in Delta Scuti stars allow scientists to better understand the internal structure, age, size, and composition of these stars?
## Mysteries of a Pulsating Star Solved, revealing a Cosmic Couple
**Host:** Welcome back to Cosmic Queries! Today, we’re diving into the fascinating world of pulsating stars. Joining us is Dr. Emily Carter, an astrophysicist specializing in stellar activity. Dr. Carter, thanks for being here.
**Dr. Carter:** Thanks for having me. It’s always exciting to talk about these celestial wonders.
**Host:** We’ve recently seen some intriguing news about a particular type of star, Delta Scuti stars, known for their subtle pulsations. Can you tell us what makes these pulsations so special, and what these recent findings mean for our understanding of these stars?
**Dr. Carter:** Absolutely! Delta Scuti stars are a class of stars that faintly pulse in brightness due to internal oscillations.
Think of it like ringing a bell – the star vibrates, and that vibration causes changes in its brightness. These pulsations are very subtle, which is why they’re challenging to detect.
**Host:** So, these pulsations are like a rhythmic heartbeat of the star?
**Dr. Carter:** Exactly! And the exciting news is that thanks to data from NASA’s TESS satellite, astronomers have discovered regular pulsation patterns in dozens of these young, rapidly rotating Delta Scuti stars [[1](https://scitechdaily.com/perplexing-stellar-pulsations-regular-rhythms-discovered-in-mysterious-pulsating-stars/)].
**Host:** What does this tell us about these stars?
**Dr. Carter:** This is a game-changer! By studying these pulsations, scientists can glean a lot of information about the star’s internal structure, its age, size, and even composition. It’s like taking a star’s vital signs and getting a much clearer picture of what’s happening inside.
**Host:** This sounds revolutionary! How will these findings impact future research?
**Dr. Carter:** This discovery opens up a whole new avenue of research. Astronomers can now use these pulsation patterns as a tool to study the evolution of stars in much greater detail than ever before.
**Host:** Dr. Carter, thank you so much for shedding light on this exciting discovery. It sounds like we’re on the verge of learning a lot more about these fascinating pulsating stars!
