. Their findings were described in 2 documents published in parallel today in the journals Nature and Nature Astronomy. The research studies were led jointly by The group is led jointly by Franz Kirsten, a postdoctoral astronomer with the Chalmers University of Technology in Sweden and ASTRON, and Kenzie Nimmo, a Ph.D. student with ASTRON and the University of Amsterdam.
As they explain in their papers, the team set out to make high-precision measurements of a duplicating FRB found in January 2020 in the constellation Ursa Major (aka. the Big Dipper). To study the source with the greatest possible resolution and level of sensitivity, the team combined measurements from multiple instruments in the European VLBI Network (EVN)– a network of telescopes situated mainly in Europe and Asia focusing on Very Long Baseline Interferometry (VLBI).
These were complemented by measurements taken from other powerful radio telescopes, like the Karl G. Jansky Very Large Array (VLA) in New Mexico. They understood the duplicating FRB came from the neighboring spiral galaxy Messier 81 (M 81) when they evaluated the measurements. This galaxy lies about 12 million light-years from Earth, making this occasion the closest FRB found to date. As Kirsten discussed in a recent Chalmers press release:
” We desired to look for ideas to the bursts origins. That provides the opportunity to see what the regional neighborhood of a quick radio burst looks like.”
A magnetar sparkles, concealed amongst ancient stars (in red) in the borders of the spiral galaxy Messier 81 (M 81). Credit: Daniëlle Futselaar, artsource.nl
Quick Radio Bursts (FRBs) are amongst the leading mysteries facing astronomers today. Discovered in 2007 (the well-known “Lorimer Burst”), these energetic events consist of big bursts of radio waves that normally last mere milliseconds. While many occasions observed to date have actually been one-off occasions, astronomers have actually detected a couple of FRBs that were repeating in nature. The cause of these bursts stays unidentified, with theories varying from turning neutron stars and magnetars to extraterrestrials!
Since the first occasion was identified fifteen years earlier, enhancements in our instruments and devoted selections have led to lots of more detections! In another turning point, a global team of astronomers recently made high-precision measurements of a repeating FRB situated in the spiral galaxy Messier 81 (M81)- the closest FRB observed to date. The groups findings have helped resolve some concerns about this mystical phenomenon while raising others.
The international group was comprised of researchers from the Netherlands Institute for Radio Astronomy (ASTRON), the Anton Pannekoek Institute for Astronomy, limit Planck Institute for Radio Astronomy, the Onsala Space Observatory, the Perimeter Institute for Theoretical Physics, the Ventspils International Radio Astronomy Centre (VIRAC), and several universities and research institutes in the Netherlands, Germany, Sweden, Canada, China, India, Italy, the U.K., and the U.S
Whats more, the team traced the FRB to the outskirts of the galaxy and recognized that it needed to be coming from a dense cluster of older stars (a globular cluster). This was a rather unforeseen discover, as numerous FRBs are surrounded by young, massive, short-term stars and lot of times the mass of our Sun. These stars end their lives as extremely thick and extremely allured white dwarves called magnetars.
” Its remarkable to discover quick radio bursts from a globular cluster,” included Kirsten. “This is a location in space where you only find old stars. Further out in the universe, fast radio bursts have been discovered in locations where stars are much younger. This needed to be something else.” As noted, astronomers have pertained to believe that FRBs are the outcome of young stars undergoing gravitational collapse to end up being magnetars. This has actually been substantiated by a considerable body of research study in the last few years.
However, these newest findings suggest that they may be linked to magnetars that formed when a white dwarf became huge adequate to collapse under its own weight– something that has been anticipated but never ever before seen. Employee Jason Hessels, a teacher with the University of Amsterdam and ASTRON, discussed:
” We anticipate magnetars to be new and glossy, and definitely not surrounded by old stars. So if what were looking at here truly is a magnetar, then it cant have actually been formed from a young star exploding. There needs to be another way.”
A brand-new composite image of the Crab Nebula includes X-rays from Chandra (blue and white), optical information from Hubble (purple), and infrared information from Spitzer (pink). Credit: NASA
In globular clusters, many stars exist as double stars, some of which get close for one star to collect product from the other. This frequently takes place when one star is no longer in its primary series and expands to become a Red Giant. The companion will begin to siphon product from the Red Dwarfs external layers, eventually causing a scenario called “accretion-induced collapse.”
” If one of the white overshadows can capture adequate extra mass from its companion, it can become an even denser star, known as a neutron star,” said staff member Mohit Bhardwaj, a Ph.D. candidate at McGill University and a member of the Canadian Hydrogen Intensity Mapping Experiment (CHIME). “Thats an unusual occurrence, however in a cluster of ancient stars, its the most basic method of making quick radio bursts.”
After zooming in on their measurements to look for additional clues, the astronomers found something else that surprised them. Some of the flashes they observed were shorter in duration than anticipated, lasting for nanoseconds (one-billionth of a 2nd) rather than milliseconds (one-thousandth).
That informs us that they need to be coming from a tiny volume in space, smaller than a soccer pitch and possibly only 10s of meters across. That suggests that we are indeed seeing a magnetar, however in a location that magnetars have not been found prior to.”
In the future, observations of this system and others like it will assist astronomers inform if the source is an unusual magnetar, an unusual pulsar, a black hole, a dense star in a close orbit, or something else entirely. Regardless, it is clear that the detection of more FRBs is leading to unexpected and new insights into FRBs and the life cycle of stars.
Initially released on Universe Today.
For more on this research, see:
Strange Cosmic Flashes Pinpointed to a Surprising Location in Space
Mystical Source of Fast Radio Bursts
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The cause of these bursts remains unknown, with theories varying from turning neutron stars and magnetars to extraterrestrials!
Whats more, the group traced the FRB to the borders of the galaxy and recognized that it had to be coming from a thick cluster of very old stars (a globular cluster). Further out in the universe, fast radio bursts have been found in places where stars are much more youthful. As kept in mind, astronomers have actually come to believe that FRBs are the outcome of young stars going through gravitational collapse to end up being magnetars. In globular clusters, lots of stars exist as binary systems, some of which get close for one star to collect product from the other.