New research on fast radio burst (FRB) has finally solved the long-standing mystery of “missing matter” in the universe. The breakthrough comes as part of another study, in which scientists for the first time have managed to determine the exact location of a fast radio burst taking place in a faraway galaxy. It was conducted using advanced optical and radio telescopes, by an international team of researchers, including experts from Germany’s Max Planck Institute of Radio Astronomy.
The FRB in question was spotted in April last year, by Australia-based Commonwealth Scientific and Industrial Research Organization’s 64-m Parkes radio telescope. For those who are unfamiliar with fast radio blasts, they are a very rare, mysterious astrophysical phenomenon, characterized by high-energy radio flashes that last only a couple of milliseconds. Being incredibly difficult to detect, only 16 of these occurrences had been observed up until now. Speaking about the research, recently published in the Nature journal, Evan Keane, the leader of the team, said:
In the past FRBs have been found by sifting through data months or even years later. By that time it is too late to do follow up observations.
To make the task easier, scientists, working for the SUrvey for Pulsars and Extragalactic Radio Bursts (SUPERB), developed a highly-specialized system that can spot FRBs in mere seconds, while also instantly alerting other telescopes to do the same. The radio signals of last year’s FRB were detected using this system. According to the researchers, the bright radio afterglow, which lasted for nearly 6 days, helped them zero in on the FRB’s location, with 1,000 times more accuracy than ever before. Analysis of the data collected by the 8.2-m Subaru telescope in Hawaii revealed that the signals were coming from an elliptical galaxy, located over 6 billion light-years away. The team added:
It’s the first time we’ve been able to identify the host galaxy of an FRB. Our analysis leads us to conclude that this new radio burst is not a repeater, but resulting from a cataclysmic event in that distant galaxy.
What is more, the discovery has allowed the scientists to study the universe’s matter content in unprecedented detail. FRBs are known to exhibit frequency-dependent dispersion, which means that any delay in the signal is likely due to the density of the material it has to cross. Previously, astronomers had to rely on only the dispersion measure. Simon Johnston of CSIRO’s Astronomy and Space Science department, explained:
By also having a distance we can now measure how dense the material is between the point of origin and Earth, and compare that with the current model of the distribution of matter in the Universe. Essentially this lets us weigh the Universe, or at least the normal matter it contains.
At present, astronomers believe that the universe is composed of 70-percent dark energy, 25-percent of dark matter and just 5-percent of ordinary, visible matter. Scientific research, over the years, has been able to account for only half of the surmised ordinary matter. The remaining part, also referred to as “missing matter”, has eluded scientists for centuries. Keane went on to say:
The good news is our observations and the model match, we have found the missing matter. It’s the first time a fast radio burst has been used to conduct a cosmological measurement.