Recently, astronomers made an astonishing discovery — a mysterious and powerful burst of radio waves reached Earth after traveling through space for 8 billion years. Dubbed FRB 20220610A, it is one of the most distant and energetic radio signals ever observed.
Fast radio bursts (FRBs), including this particular one, are extremely intense flashes of radio waves that last only milliseconds, yet their origins remain a source of great intrigue and perplexity. We still don’t know what, or who, sends these energy bursts.
The nature of these signals challenges our understanding of the universe, as they can originate from regions far beyond our Milky Way galaxy, hinting at processes and events that we are only beginning to comprehend.
Dr. Stuart Ryder, an esteemed astronomer at Macquarie University in Australia, is among the dedicated team of scientists working diligently to unravel the mysteries surrounding this cosmic enigma.
Through advanced technologies and collaborative efforts, they aim to decode the origins and implications of these fast radio bursts, potentially unlocking new insights into the fundamental workings of our universe and the forces that shape it.
Understanding fast radio bursts (FRBs)
Fast radio bursts, or FRBs, are intense flashes of radio waves that last for just milliseconds. They were first discovered in 2007, and ever since, they have captured the curiosity and fascination of the scientific community worldwide.
For instance, this recent FRB emitted energy equivalent to what our sun produces over 30 years — and all in less than a blink of an eye.
Researchers speculate that these cosmic events might be linked to magnetars, the highly energetic remnants left behind by exploding stars.
Astronomers deployed the Australian Square Kilometre Array Pathfinder (ASKAP) to detect the burst and track down its origin.
“We used ASKAP’s radio dishes to skillfully pinpoint where the burst came from,” says Dr. Ryder.
The reveal didn’t end there. The team also located the source galaxy using the European Southern Observatory’s Very Large Telescope, discovering it to be older and more distant than any other FRB source found to date.
‘Weighing’ the universe with FRBs
Believe it or not, these fleeting cosmic fireworks could help us ‘weigh’ the universe. There’s a discrepancy between the amount of normal matter we can detect and what cosmologists theorize should exist. Could the answer be outside our visual spectrum?
“More than half of the normal matter that should exist today is missing,” says Professor Ryan Shannon. He suggests that this ‘missing’ matter might be hiding in the vast spaces between galaxies, where it’s too hot and diffuse to see with conventional methods.
Enter FRBs. Their unique ability to ‘sense’ the ionized material in nearly empty space allows scientists to measure the matter located between galaxies.
This method, established in 2020 by the late Australian astronomer Jean-Pierre Macquart, is now known as the Macquart relation.
“This detection confirms the Macquart relation, even for bursts halfway across the known universe,” adds Ryder.
New telescopes will soon join the search
Nearly 50 FRBs have been traced back to their origins, and about half were discovered using the ASKAP telescope.
Despite the unknown causes of these enormous bursts, one thing is certain: FRBs are common events in the cosmos and have enormous potential for advancing our understanding of the universe.
Professor Shannon believes that future radio telescopes, currently under construction, will detect thousands more FRBs.
“FRBs are common and hold great promise,” he says. “We could use them to create a new map of the universe’s structure and answer big questions about cosmology.”
Missing matter mystery
The universe is enormous, and much of it still baffles us, especially the disparity between observable and theoretical matter.
This “missing matter” refers to a significant amount that should be there according to our current models of cosmic evolution but hasn’t been seen.
It turns out that visible matter — like stars, planets, and galaxies — makes up only about 5% of the universe’s total mass-energy content. The other 95% is thought to be dark matter and dark energy, which we can’t directly detect. This gap raises some big questions about how the universe is structured and behaves.
Researchers think that this missing matter might exist in forms that are hard to spot, like hydrogen gas floating in the intergalactic medium.
Recent studies with advanced telescopes have started to find these elusive hydrogen clouds, suggesting that a significant chunk of the universe’s matter could be hiding in this diffuse state.
Figuring out what this missing matter is and where it’s located is key to getting a complete picture of cosmic evolution and fine-tuning our models of how the universe works.
Fortunately, the discovery of FRBs and their ability to trace hidden matter could revolutionize how we understand the cosmos. As Professor Shannon points out, even in nearly empty space, FRBs can ‘see’ electrons and measure the matter present.
Exciting future of FRB research
With more advanced radio telescopes on the horizon, the future of FRB research is looking bright. Each new detection brings us closer to unveiling the secrets of these powerful cosmic events.
Beyond mapping the universe’s structure, FRBs could guide us to fundamental questions about the inner workings of the universe — aligning us closer with the cosmic forces and events that shape our cosmos.
Despite our growing knowledge base, FRBs remain one of the universe’s great mysteries. As researchers venture deeper into the study of these cosmic flashes, one thing becomes clear: we still know very little about the universe in which we live.