Scientists have detected the largest-ever fast radio burst (FRB) and, intriguingly, it originates from beyond our Milky Way galaxy.
The signal traveled at least a billion light-years to reach Earth and lasted for just one second. Nonetheless, it has provided us with some insight into the seemingly boundless void, the space between galaxies known as the cosmic web, where all cosmic matter is distributed in a network-like structure.
“These FRBs, though very short-lived, are incredibly powerful radio bursts,” said astrophysicist Ryan Shannon from the University of Australia. “Some bursts are detected quite randomly, and no two bursts are exactly alike.”
We still know very little about these phenomena known as FRBs: where they come from, what cosmic events produce them, and why we haven’t detected more of them until now.
This particular burst is called FRB 150807, and while the number may suggest otherwise, it is only the 18th FRB detected since they were first discovered in 2001. It’s a known fact that scientists aren’t very creative when it comes to naming.
Although this event seems rare, occurring only once a year, many scientists believe that FRBs are quite common, but we simply haven’t been able to detect them.
“We estimate that there are about 2,000 to 10,000 of these FRB events happening in the sky every day,” said astronomer Vikram Ravi, part of the research team.
The place believed to have emitted FRB 150807.
Typically, FRBs happen so rapidly that pinpointing their location is extremely challenging. Even the telescopes that detect FRBs cannot precisely determine their origins because their primary mission is to observe large portions of the universe.
However, this time, FRB 150807 was significant enough to allow us to trace its source, providing us with new clues about how cosmic matter “lands” on Earth from beyond the Milky Way.
This FRB event marks the first time we’ve obtained detailed information about the cosmic web.
“This is the first time I’ve seen an FRB that contains information about the cosmic web – the supposed fabric of the universe,” said Professor Shannon.
Furthermore, we can reconstruct its trajectory and potentially find the point of origin for this explosive radio burst, which could be located billions of light-years away and potentially house galaxies capable of supporting life.
As FRBs traverse the universe, they encounter various materials such as gas, ionized particles, and electromagnetic fields, causing radio waves to distort.
However, in this case, when the Parkes Observatory in Australia detected FRB 150807, researchers noticed minimal distortion, indicating that the cosmic dust and electromagnetic fields throughout the cosmic web were less chaotic than those within our Milky Way.
They also identified potential sources for this powerful radio wave burst, with the star system VHS7 being a possible candidate for the origin of FRB 150807.
This galaxy is located approximately 3.2 to 6.5 billion light-years away, making it uncertain whether this FRB event originates from there. There could be a smaller, less luminous galaxy that we have yet to discover.
Nevertheless, we have gained valuable information from this discovery. Many scientists previously doubted that FRBs originated within our Milky Way, and the detection of FRB 150807 has shed light on this uncertainty.
“I think this time, things have been clarified,” said astronomer James M. Cordes from Cornell University. “Perhaps only one or two of the 18 burst events are from our galaxy, with the rest likely coming from other galaxies.”
Although we still don’t understand what causes these FRBs, this discovery has provided us with a slightly clearer glimpse into this microscopic-scale cosmic phenomenon.
Refer to ScienceAlert.