Mysterious radio waves from space, which took 8 billion years to reach Earth, have been successfully detected. Could their source be extraterrestrial life? Astronomers believe that this discovery represents one of the farthest and most energetic radio wave emissions ever observed.
Fast Radio Bursts (FRBs) are extremely powerful radio waves that last for milliseconds and have an unknown origin. The first FRB was discovered in 2007, and since then, hundreds of these rapid cosmic flashes have been detected coming from distant points in the universe.
The radio wave burst, named FRB 20220610A, lasted less than one millisecond, but during that fraction of a second, it released energy equivalent to the Sun’s energy emissions over 30 years, according to a recent study published in the journal Science.
Many FRBs emit extremely bright radio waves that last for only a few milliseconds before disappearing, making fast radio bursts challenging to observe.
Radio telescopes, including the ASKAP radio telescope located in Wajarri Yamaji Country, Western Australia, have assisted astronomers in tracking these rapid cosmic flashes. Astronomers used ASKAP to detect the FRB in June 2022 and determine its origin.
“By using the ASKAP radio array, we can precisely determine the source of the burst,” said co-author Stuart Ryder, an astronomer at Macquarie University in Australia, in a statement quoted by CNN on Thursday, October 19.
“We then used the European Southern Observatory’s Very Large Telescope in Chile to search for the source galaxy and found that the galaxy is older and farther away than any other FRB source discovered to date and likely part of a small group of merging galaxies.”
The research team traced the radio burst to what appears to be a cluster of two or three galaxies that are in the process of merging, interacting, and forming new stars.
This finding aligns with the current theory that fast radio bursts may originate from magnetars, high-energy objects produced by star explosions.
Scientists believe that fast radio bursts could be a unique method for “weighing” the universe by measuring the matter between galaxies that remains unknown.
“If we count the amount of normal matter in the universe – the atoms that make up all of us – we find that more than half of what should be there is missing,” said one of the study’s authors, Ryan Shannon, a professor at Swinburne University of Technology in Australia, in a statement.
Ryan Shannon speculated that the missing matter is dispersed in extremely hot conditions. “We suspect that the missing matter is hiding in the intergalactic space, but it might be so hot and spread out that it is impossible to see with normal techniques.”
So far, the results from the methods used to estimate the mass of the universe do not match.
“Fast radio bursts detect this ionized matter,” Shannon said. “Even in nearly perfect empty space, they can ‘see’ all the electrons, allowing us to measure how much matter exists between galaxies.”
The use of fast radio bursts to detect this missing matter was demonstrated by the late Australian astronomer Jean-Pierre (J-P) Macquart in 2020.
“J-P showed that the farther the fast radio burst, the more gas is scattered between galaxies. This is now known as the Macquart relation,” Ryder said.
“Recent fast radio bursts seem to break this relationship. Our measurements confirm that the Macquart relation holds for more than half of the known universe.”
Almost 50 fast radio bursts have been traced to their source so far, with about half of them discovered using ASKAP.
“The fact that FRBs are found to be very common is also amazing,” Shannon said.
“This demonstrates how promising this field is because you won’t just do this for 30 bursts, you could do it for 30,000 bursts, creating a new map of the structure of the universe and using it to answer significant questions about cosmology,” he concluded.
