Astronomers have detected the oldest-known fast radio burst (FRB), a mysterious flash of radio waves that lasted less than a millisecond but unleashed the amount of energy our sun emits in three decades.
A drawing shows the long journey through space of a fast radio burst that began in distant galaxies and reached Earth 8 billion years later – Source: REUTERS
The burst was detected using the Australian SKA Pathfinder, a radio telescope in the state of Western Australia. Its location was pinpointed by the European Southern Observatory’s Very Large Telescope in Chile, one of the most powerful optical telescopes.
The burst is estimated to have occurred about 8 billion years ago, making it 3 billion years older than the previous oldest-known FRB. This means that FRBs have been around for more than half the age of the universe.
FRBs were first discovered in 2007, but their origin remains a mystery. The most likely source is thought to be a hyper-magnetized neutron star, called a magnetar. These stars are stellar corpses the mass of the sun but only the size of a small city. They are some of the most extreme objects in the universe, which is needed to produce such extreme bursts.
The researchers said that studying these bursts also can help to detect and measure the immense amount of matter believed to populate the expanses of space between galaxies. As these radio waves zip though the cosmos, they can flag the presence of this intergalactic plasma – gas so hot that some or all its atoms are split into the subatomic particles electrons and ions.
“Most of the normal matter in the universe – this is the regular matter that makes up stars, planets, humans – is thought to reside in a diffuse cosmic web of gas between galaxies,” said astronomer Ryan Shannon of Swinburne University of Technology in Australia, co-leader of the study. “People have been searching for this matter for decades using other techniques. Because it is so diffuse, it is nearly invisible in any other way, so was considered ‘missing.’”
The discovery of this new FRB is a significant step forward in our understanding of these mysterious objects. It shows that FRBs are more common than previously thought and that they have been around for a very long time. The researchers hope that by studying more FRBs, they will be able to learn more about their origin and the role they play in the universe.
