Astronomers estimate that the signal comes from a galaxy about a billion light-years away, but the exact location and cause of the explosion is unknown. A study detailing the results published Wednesday in the journal Nature.
Rapid bursts of radio, or FRBs, are intense bursts of radio waves lasting milliseconds of unknown origin. The first FRB was discovered in 2007, and since then, hundreds of these fast cosmic flashes have been detected from various distant points in the universe.
Many FRBs release super bright radio waves that only last a few milliseconds at most before disappearing completely, and it is known that about 10% of them repeat and have patterns.
One resource used to detect them is a radio telescope called the Canadian Hydrogen Intensity Mapping Experiment, or CHIME, at the Dominion Radio Astrophysical Observatory in British Columbia, Canada.
This telescope, in operation since 2018, constantly observes the sky and, in addition to the rapid bursts of radio, is sensitive to radio waves emitted by distant hydrogen in the universe.
Astronomers using CHIME detected something on December 21, 2019 that immediately caught their attention: a fast radio that was “peculiar in many ways,” according to Daniele Michilli, a postdoctoral researcher at the Kavli Institute of Astrophysics and Space of the Massachusetts Institute of Technology. Research.
The signal, called FRB 20191221A, lasted up to three seconds, which is about 1,000 times longer than typical fast radio bursts.
Michilli was monitoring the data as it came from CHIME, when the explosion occurred. The signal is the most enduring fast radio to date.
“It was unusual,” Michilli said. “Not only was it very long, lasting about three seconds, but there were periodic peaks that were remarkably accurate, emitting every fraction of a second — album, boom, boom — like a heartbeat. This is the first time that the signal itself is periodic. “
Although FRB 20191221A has not yet been repeated, “the signal consists of a train of consecutive peaks that we found separated by ~ 0.2 seconds,” he said in an email.
An unknown source
The research team does not know the exact galaxy from which the eruption originated and even the estimate of the distance of a billion light-years is “very uncertain,” Michilli said. While CHIME is ready to look for bursts of radio waves, it’s not as good at locating its points of origin.
However, CHIME is being upgraded through a project where additional telescopes, currently under construction, will observe together and be able to triangulate radio bursts into specific galaxies, he said.
But the signal contains clues as to where it came from and what may have caused it.
“CHIME has now detected many FRBs with different properties,” Michilli said. “We have seen some living inside very turbulent clouds, while others appear to be in clean environments. From the properties of this new signal, we can say that around this source, there is a plasma cloud. which must be extremely turbulent. “
When the researchers analyzed FRB 20191221A, the signal was similar to the emissions released by two different types of neutron stars, or dense debris after the death of a giant star, called radio and magnetic pulsars.
Magnetars are neutron stars with incredibly powerful magnetic fields, while radio pulsars release radio waves that appear to pulsate as the neutron star rotates. Both stellar objects create a signal similar to the flashing beam of a lighthouse.
Fast radio seems to be over a million times brighter than these broadcasts. “We think this new signal could be a magnet or a pulsar with steroids,” Michilli said.
The research team will continue to use CHIME to monitor the sky to find more signals from this radio as well as others with a similar periodic signal. The frequency of radio waves and how they change could be used to help astronomers learn more about the speed of the universe’s expansion.
“This detection raises the question of what could cause this extreme signal we had never seen before and how we can use this signal to study the universe,” Michilli said. “Future telescopes promise to discover thousands of FRBs a month, and right now we can find many more of these periodic signals.”