Astrophysicists have discovered for the first time a burst of cosmic radio waves in our galaxy and have identified its source, according to a study published Wednesday that sheds light on one of the mysteries of the universe.
The origin of powerful fast radio bursts (FRBs) – intense bursts of radio emission that last only a few milliseconds – have puzzled scientists since they were first detected just over a decade ago.
They are usually extragalactic, that is, they occur outside our galaxy, but on April 28 this year, several telescopes detected a bright burst of radiation from the same region within our Milky Way.
Importantly, they were also able to identify the source: the galactic magnetar SGR 1935 + 2154.
Magnetars, young neutron stars that have the strongest magnetic field in the universe, have long been prime targets in the search for the source of these radio bursts.
But the discovery marks the first time that astronomers have been able to directly trace a signal to a magnetar.
Christopher Bochenek, Radio Emission 2 (STARE2) with one of the teams that detected the burst, said that in about a millisecond, a magnetar emits as much energy as the Sun emits in 30 seconds.
He said the surge was' so bright 'that in theory, if you had a raw data record from your cell phone's 4G LTE receiver and knew what to look for,' you could find this signal, which came about halfway across the galaxy. 'to the phone data.
This energy is comparable to radio bursts outside the galaxy, he said, adding to the argument that magnetars are the source of most extragalactic bursts.
Up to 10,000 surges can occur each day, but these high-energy surges were only discovered in 2007.
Since then, they have been the subject of heated debate, and even small steps towards determining their origin have aroused great interest among astronomers.
One problem is that instant flashes are hard to spot without knowing where to look.
Theories of their origins have ranged from catastrophic events such as supernovae to neutron stars, which are superdense stellar fragments formed after the gravitational collapse of a star.
There are more exotic explanations for extraterrestrial signals that astronomers do not account for.
The latest discovery, published in three articles in the journal Nature, was made by combining observations from space and ground-based telescopes.
Both STARE2 and the Canadian Hydrogen Intensity Mapping Experiment (CHIME) detected the flare and attributed it to the magnetar.
Later that day, this region of the sky was seen by an extremely sensitive 500 meter spherical telescope (FAST) in China.
“The flash from the magnetar collides with the environment and thereby generates a shock wave,” the researchers wrote, adding that the results highlight the need for international cooperation in astronomy and monitoring of various types of signals.
Sources: Photo: Sophia Dagnello, NRAO / AUI / NSF