Record-distant radio flash traced to a tiny, young galaxy
Astronomers have traced the most distant fast radio burst yet to a small, young galaxy. The flash of radio waves lasted only milliseconds and traveled more than 10 billion years to reach Earth. The find, published in Science, points to young magnetic stars called magnetars as a likely cause of these mysterious bursts.
A flash of radio waves that lasted a few thousandths of a second has given astronomers a new clue to one of space's lasting puzzles.
The signal, called FRB 20240304B, is the most distant fast radio burst yet tied to its home galaxy. It traveled more than 10 billion years before reaching Earth, according to the South African Radio Astronomy Observatory. That is more than double the old distance record, The Independent reported. The study was published Thursday in the journal Science.
Fast radio bursts were first found in 2007. They are short, very powerful bursts of radio energy, and scientists still do not know what makes them. Most are seen only once, which makes them hard to study.
South Africa's MeerKAT radio telescope caught this burst on March 4, 2024. Large telescopes on the ground could not see any galaxy at that spot. So the team turned to NASA's James Webb Space Telescope, which found a faint galaxy in the right place.
That galaxy was a surprise. Most galaxies with these bursts are large and full of stars. This one was about 1,000 times less massive than expected, the European Space Agency said. It was young and forming stars quickly.
"We thought it would be a big, nicely formed galaxy with lots of stars, and instead it was a little dwarf galaxy," said lead author Manisha Caleb of the University of Sydney.
The finding matters for the cause. One idea is that bursts come from two neutron stars crashing together, which takes billions of years. A young galaxy points instead to magnetars, young neutron stars with very strong magnetic fields. "Our work suggests that it's very unlikely that this FRB was produced by a merger," Caleb said. Her team noted that not all bursts may share the same cause.
The signal also picked up traces of matter it passed through, including a galaxy cluster no one knew about. The team expects MeerKAT to find several more very distant bursts each year.
What we know: The burst came from a small, young galaxy when the universe was about 3 billion years old.
What we don't: Whether all fast radio bursts come from magnetars.
Where outlets agree The Independent and ESA/Webb both report that the burst began about 3 billion years after the Big Bang.
Where they differ Space.com says the burst offers a look at 11 billion years of cosmic evolution, while The Independent says it traveled for 10 billion years to reach Earth.