Researchers Detect Ancient Energetic Burst
2023-10-27
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1Astronomers have detected radio waves coming from what looks like a joining of galaxies from about 8 billion years ago.
2The discovery is the oldest-known example of an event that is difficult to explain: a fast radio burst.
3In less than a millisecond, this burst released the amount of energy our sun releases in thirty years, scientists said.
4The Australian SKA Pathfinder, a radio telescope in the state of Western Australia, detected the burst.
5And the European Southern Observatory's Very Large Telescope in Chile, one of the most powerful telescopes, found the location of the burst.
6A fast radio burst, or FRB, is a kind of radio-frequency electromagnetic radiation.
7It lasts less than a millisecond but outshines most other sources of radio waves in the universe.
8Radio waves have the longest wavelengths in the electromagnetic spectrum.
9Ryan Shannon, an astronomer at Swinburne University of Technology in Australia, was a co-leader of the study published recently in Science.
10He said radio waves in FRBs are similar to those used in microwave ovens.
11And he added that this FRB had the same amount of energy needed to microwave "a bowl of popcorn twice the size of the sun."
12Until now, the oldest-known such burst dated to 5 billion years ago, making this one 3 billion years older.
13The universe is about 13.8 billion years old. For comparison, Earth is about 4.5 billion years old.
14In seeing objects and events from long ago, researchers look across large distances, making this burst also the farthest of any FRB ever detected.
15"We now know that fast radio bursts have been around for more than half the age of the universe," said study co-leader Stuart Ryder of Macquarie University in Australia.
16Researchers first discovered fast radio bursts in 2007.
17The most likely source is a special kind of "neutron star, called a magnetar. These stars ... are some of the most extreme objects in the universe, which you would need to produce such extreme bursts," Shannon said.
18"There are more energetic events in the universe, associated with stellar explosions or a black hole shredding a star apart.
19But FRBs are unique in that they produce all their energy in radio waves, with nothing seen in other bands - optical light or X-rays for example - and that the signals are so short," Shannon added.
20They also are more common, Shannon explained, with around 100,000 thought to happen somewhere in the universe daily.
21Far fewer have been detected, Shannon said, and only around 50 - including this one - have been traced back to the galaxy where they began.
22The scientists said that studying these bursts can help to detect and measure the large amount of matter believed to populate the large distances of space between galaxies.
23I'm John Russell.
1Astronomers have detected radio waves coming from what looks like a joining of galaxies from about 8 billion years ago. The discovery is the oldest-known example of an event that is difficult to explain: a fast radio burst. 2In less than a millisecond, this burst released the amount of energy our sun releases in thirty years, scientists said. 3The Australian SKA Pathfinder, a radio telescope in the state of Western Australia, detected the burst. And the European Southern Observatory's Very Large Telescope in Chile, one of the most powerful telescopes, found the location of the burst. 4A fast radio burst, or FRB, is a kind of radio-frequency electromagnetic radiation. It lasts less than a millisecond but outshines most other sources of radio waves in the universe. Radio waves have the longest wavelengths in the electromagnetic spectrum. 5Ryan Shannon, an astronomer at Swinburne University of Technology in Australia, was a co-leader of the study published recently in Science. 6He said radio waves in FRBs are similar to those used in microwave ovens. And he added that this FRB had the same amount of energy needed to microwave "a bowl of popcorn twice the size of the sun." 7Until now, the oldest-known such burst dated to 5 billion years ago, making this one 3 billion years older. The universe is about 13.8 billion years old. For comparison, Earth is about 4.5 billion years old. 8In seeing objects and events from long ago, researchers look across large distances, making this burst also the farthest of any FRB ever detected. 9"We now know that fast radio bursts have been around for more than half the age of the universe," said study co-leader Stuart Ryder of Macquarie University in Australia. 10Researchers first discovered fast radio bursts in 2007. 11The most likely source is a special kind of "neutron star, called a magnetar. These stars ... are some of the most extreme objects in the universe, which you would need to produce such extreme bursts," Shannon said. 12"There are more energetic events in the universe, associated with stellar explosions or a black hole shredding a star apart. But FRBs are unique in that they produce all their energy in radio waves, with nothing seen in other bands - optical light or X-rays for example - and that the signals are so short," Shannon added. 13They also are more common, Shannon explained, with around 100,000 thought to happen somewhere in the universe daily. Far fewer have been detected, Shannon said, and only around 50 - including this one - have been traced back to the galaxy where they began. 14The scientists said that studying these bursts can help to detect and measure the large amount of matter believed to populate the large distances of space between galaxies. 15I'm John Russell. 16Will Dunham reported on this story for Reuters. John Russell adapted it for VOA Learning English. 17________________________________________________ 18Words in This Story 19detect -- v. to discover or notice the presence of something 20burst - n. a short period of producing or doing something that begins suddenly 21millisecond - n. one-thousandth of a second 22location -- n. a place or position 23neutron star - n. a small and very dense kind of stellar object 24stellar - adj. of or relating to the stars 25shred - v. to cut or tear (something) into long pieces 26unique -- adj. used to say that something or someone is unlike anything or anyone else 27trace -- v. to follow something back to its cause or beginning