Fast radio bursts (FRB) are one of the most puzzling phenomena faced by astronomers today. Essentially, FRBs are short radios from distant astronomical sources, the cause of which remains unknown. In some cases, FRBs were found, which were repeated, but most were one-off events. And while repeated sources have been traced to their place of origin, no events have been localized so far.
So far. The use of the Australian square kilometer Pathfinder (ASKAP) and other radio telescopes from around the world, led by an Australian astronomy team, confirmed the distance to an intense radio burst that flashed for only a thousandth of a second. It consists of the first non-recurring FRB traced to its source, which in this case is a galaxy located at 4 billion light-years.
Since the first FRB was discovered in 2007 ("Lorimer Burst"), radio astronomers are eagerly awaiting a chance to observe more. To date, forty events (most of which are extracted from archive data) and a handful of traces back to their sources have been found. Still, astronomers still do not know what causes them, with theories ranging from fast rotating neutron stars and black holes to alien radio signals.
The discovery of the FRB is quite challenging, as most of them are only a millisecond, and tracking them to their source is even more difficult. In this case, the FRB (known as FRB 180924) is a single burst that disappears as suddenly as it may seem – unlike others that may blink several times for an extended period of time. The results are published in a recent study . The first impulse was noticed by ASKAP researchers in 2018 during a special search from the antennas of the 36 radio telescopes of the array. Researchers then used the minimum time differences to reach the signals to the various antennas in the array to locate the source of the impulse. From these differences they managed to determine the initial galaxy of the blast.
As Adam Deller, a researcher at the Swinburne Technological University and lead author of the study, explained:
"When we were able to get a FRB 180924 position that was good at 0.1 angular second, we knew you would tell us not only which object is the host galaxy, but also where the host galaxy has happened. We found that the FRB is located away from the galaxy's core, in the "galactic suburbs".
The team then attracted the help of researchers from the Gemini South telescope and the very large ESO telescope (VLT). in Chile and WM Observatory Keck in Hawaii to monitor the galaxy and determine its distance and other characteristics. The Gemini Telescope is particularly useful as it has been designed with these observations.
This is because the 8.1-meter Gemini South telescope is designed to deliver high-quality images and depths in optical and infrared wavelengths. However, the combined efforts of these three observatories and their advanced set of tools made it possible to locate the galaxy.
Nicola Teyos, a researcher from the Catholic University of Valparaiso in Chile, leads Gemini's observations. As explained in a Gemini Observatory statement: "The Middle South data absolutely confirmed that the light had left the galaxy about 4 billion years ago … ASCAP has given us a two-dimensional position in the sky, but the Twins, Keck and VLT observations, locked at a distance that ends the three-dimensional picture. "The knowledge of where this type of FRB is in the galaxy is important to astronomers, because it allows them to find some hint of what the birthplace might be. So far, most origins theories include a massive, compact object (ie a neutron star or a black hole), so knowing where the FRB is within a galaxy can tell astronomers whether this is formation, evolution, or crash / destruction of these objects,