The Magnetar SGR 1935 + 2154, which in April launched the first known fast radio explosion from within the Milky Way, erupted again, giving astronomers another opportunity to solve more than one major cosmic mystery.
On October 8, 2020, the Ringing / FRB The collaboration revealed the SGR 1935 + 2154 version that emits three millisecond radio bursts in three seconds. Follow up Ringing / FRB The FAST Radio Telescope has discovered something else – a pulsating radio emission that corresponds to the period of rotation of the magnetic star.
“ It is really exciting to see the SGR 1935 + 2154 again, and I am optimistic that as we study these bursts more carefully, they will help us better understand the potential relationship between magnetic stars. Fast radio burstsAstronomer Deborah Judd from the University of British Columbia in Canada, and a member of Ringing / FRB, He told ScienceAlert.
Before April of this year, only fast radio bursts (FRBs) were detected coming from outside the galaxy, usually from sources millions of light-years away. The first was discovered in 2007, and since then, astronomers have been trying to figure out what causes it.
As the name suggests, FRBs are bursts of extremely powerful radio waves detected in the sky, some of which release more energy from hundreds of millions of suns. It lasts a thousandth of a second.
Since most sources of wireless bursts appear to ignite once and their frequency is not detected, they are not predictable at all. In addition, the ones that we discover usually come from very far away, and our telescopes are not able to capture individual stars. Both of these characteristics make FRBs a challenge to track down exactly the source of a galaxy, or a known cause.
But the SGR 1935 + 2154 is only about 30,000 light-years away. On April 28, 2020, it released a powerful millisecond blast, which has since been named FRB 200428 in line with the naming conventions for rapid burst radio.
Once the signal strength for distance corrected, it was found that FRB 200428 is not as strong as rapid out-of-galactic radio bursts – but everything else about it fits into the profile.
“If the same signal came from a nearby galaxy, such as one of the typical FRB nearby, it would look like FRB to us,” astronomer Shrinivas Kulkarni of the California Institute of Technology told ScienceAlert in May. “Something like this has never been seen before.”
We don’t know much about the new three bursts yet. As scientists are still working on the data, some early conclusions are likely to change, Judd told ScienceAlert. But we can already say that they are the same and not the same as FRB 200428.
They are getting less powerful again, but they are all It’s still incredibly powerful, And it’s all only milliseconds. “Although they are less bright than the discovery that was revealed earlier this year, they are still very bright streams. We will see if they are outside the galaxy,” Judd said.
“One of the most interesting aspects of this finding is that our three bursts appear to have occurred during one period of rotation. The magnetar is known to rotate once every approximately 3.24 seconds, but our first and second bursts were separated by 0.954 seconds, the second and third were separated by 1.949 seconds. This is a bit unusual, and I think it is something that we will look forward to in the future. “
This can reveal something new and useful about magnetic behavior, because – let’s face it – it’s so weird.
Magnets – which we have them Only 24 confirmed so far – a type of neutron star; This is the collapsed core of a dead star that is not massive enough to turn into a Black hole. Neutron stars are small and dense, with a diameter of about 20 kilometers (12 miles), and a maximum mass of about two suns. But magnetic stars add one more thing to the mix: an amazingly powerful magnetic field.
These amazing fields are around A quadrillion times stronger than Earth’s magnetic field, And a thousand times more powerful than an ordinary neutron star. And we still don’t fully understand how they got this way.
But we do know that magnetic stars go through periods of activity. As gravity tries to hold the star together – an internal force – the magnetic field, which is pulling outward, is so strong that it distorts the star’s shape. This leads to a continuous tension that sometimes produces giant stellar earthquakes and giant magnetic flares.
The SGR 1935 + 2154 was subject to such activity, indicating a link between magnetic tantrums and at least some FRBs.
Astronomers have clearly found the source of the first FRB within the galaxy of great interest. when Ringing / FRB Other astronomers reported their discovery, and went to glimpse the star, including a team led by Zhu Weiwei from the National Astronomical Observatories in China who had access to FAST, the largest single-aperture radio telescope in the world.
And they found something interesting, also reported on The Astronomer’s Telegram – Pulsed radio emission. These radio pulses were not close to the strength of the pulses, but they were extremely rare: if validated, the SGR 1935 + 2154 would be only the sixth magnetic star with a pulsed radio emission. He found the pulse period to be 3.24,781 seconds – exactly the period of the star’s rotation.
This is intriguing, because until now, astronomers have struggled to find a link between ferromagnetic stars and the radio Pulsars. Pulsars are another type of neutron star. They have a more natural magnetic field, but they pulsate in radio waves as they rotate, and astronomers have long tried to figure out how the two types of stars are related.
Earlier this year, Australian astronomers identified a magnetic star that was behaving like a pulsar – a possible “missing link” between the two, and evidence that at least some magnetic stars could develop into pulsars. The SGR 1935 + 2154 may be another piece of the puzzle.
“Based on these results and the increased activities of the explosion, we expect the magnetic star to be in the process of becoming a radio pulsar.” Weiwei team wrote.
Save my name, email, and website in this browser for the next time I comment.
Fast radio burst, Galaxy, Magnetar, Milky Way, Pulsar, Astronomy, Neutron star
World news – CA – The first star in our galaxy has caught on sending out fast radio bursts and is doing it all over again