Astronomers Found Cosmic Radio Burst Source:
A burst of cosmic radio waves has been detected by the astrophysicist in our galaxy for the first time and identified it’s the source. They tracked that fast radio burst to a unique type of star called a magnetar. It is said to be 32,000 light-years from Earth, according to four studies in Wednesday’s journal Nature.
The emergence of powerful and fast radio bursts (FRBs)(Intense flashes of radio emission that only last a few milliseconds) has bewildered scientists since they were first detected over a decade ago.
The FRBs are typically extragalactic, that means they originate outside our galaxy. But this year on April 28, multiple telescopes detected a bright FRB within our Milky Way galaxy coming from the same area.
Most importantly, they were also able to pin down the Source: Galantic Magnetar SGR 1935+2154.
Magnetar: The Source of FRB
Magnetars(young neutron stars that have ultra-strong magnetic fields and are the most magnetic objects in the universe)have been the prime suspect in the hunt for the source of these radio bursts for a long time.
But astronomers were able to directly trace the signal back to the magnetar for the very first time.
Caltech radio astronomer Christopher Bochenek said that in about a millisecond the magnetar emitted energy approximately equal to the energy emitted by the Sun’s radio waves in 30 seconds.
He also said the burst was “so bright” that theoretically if you had a recording of the raw data from your mobile phone’s 4G LTE receiver and had an idea of what to look for, “you might have found this signal that came about halfway across the galaxy” in the phone data. Astonishing! Right?
Topic Of Heated Debate Among Scientist:
According to scientists, these flashes are so frequent that they may happen 1,000 times or more a day outside our galaxy. But finding them isn’t easy at all.
They have been the topic of heated debate ever since they were discovered, with even small steps towards identifying their origin, stirring major excitement for astronomers.
One major problem is that the momentary flashes are very difficult to pinpoint without knowing where to look.
“You had to be looking at the right place at the right time,” Cornell’s Chatterjee said. “You’re not going to see one of these until you were extremely lucky.”
Many theories for their origin ranged from catastrophic events like supernovas to neutron stars, which are super-dense stellar fragments formed after the gravitational collapse of a star were given by the scientists.
Key to the puzzle:
The Canadian Hydrogen Intensity Mapping Experiment and STARE2 both had spotted the flare and attributed it to the magnetar.
Later the same day, this region of the sky came into the field of vision of the extremely sensitive Five Hundred Meter Aperture Spherical Telescope (FAST) in China.
According to Bing Zhang(a researcher at the University of Nevada and part of the team reporting on the discovery) astronomers, there were already keeping an eye on the magnetar, which had already entered an “active phase” and was firing off gamma-ray and X-ray bursts.
Amanda Weltman and Anthony Walters (members of High Energy Physics, Cosmology and Astrophysics Theory Group at the University of Cape Town) said that the relation of the FRB to a magnetar “potentially solves the key puzzle“.
But they also said that findings also open up a variety of new questions, such as what mechanism would produce “such bright as well as rare, radio bursts with X-ray counterparts?”
They wrote”One of the possibilities is that a flare from a magnetar collides with the surrounding medium and thereby generates a shock wave,” also including that the findings highlight the need for international cooperation in astronomy and also monitoring of different types of signals.