[ti:Astronomers Discover Most Distant Star on Record]
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[00:00.04]Space scientists say they have identified
[00:04.68]the most distant star ever recorded.
[00:09.76]Astronomers made the discovery
[00:12.84]with the Hubble Space Telescope,
[00:15.72]operated by the American space agency NASA.
[00:22.04]Researchers estimated the star was 50 to 100 times
[00:28.44]the mass of our sun, and millions of times brighter.
[00:34.28]It takes billions of years for light
[00:37.80]from distant stars to reach Earth.
[00:41.60]The team said the star’s light is believed to have traveled
[00:47.60]for 12.9 billion years before reaching our planet.
[00:54.04]This means the star would have existed when the universe
[01:00.00]was about seven percent of its current age.
[01:04.44]A member of the research team, Brian Welch,
[01:09.68]named the extremely hot and bright star Earendel.
[01:15.48]That is an Old English name that means morning star or rising light.
[01:23.56]“We’re seeing the star as it was about 12.8 billion years ago,
[01:30.68]which puts it about 900 million years after the Big Bang,” Welch said.
[01:39.32]He is a doctoral student
[01:42.32]at Johns Hopkins University in the state of Maryland.
[01:47.24]He was the lead writer of a study
[01:50.88]describing the finding in the publication Nature.
[01:56.60]The Big Bang is the explosion
[01:59.68]that many scientists believe created the universe.
[02:04.92]“We definitely just got lucky,” Welch said of the discovery.
[02:11.32]Although scientists on Earth can now see its light,
[02:17.12]Earendel itself surely no longer exists, Welch said.
[02:23.60]This is because such huge stars have short lives.
[02:29.80]The star probably existed for a few hundred million years
[02:36.04]before dying in a supernova explosion, Welch added.
[02:42.76]The previous record-holder is named Icarus.
[02:47.24]It is a similar, huge star observed by Hubble.
[02:52.76]It is believed to have formed 9.4 billion years ago.
[02:59.44]In both cases, astronomers were able to see the light
[03:04.96]from the star because of an effect known as gravitational lensing.
[03:12.32]It is the result of gravity from groups of closer galaxies
[03:18.32]between Earth and the star.
[03:21.64]The gravity acts like a lens
[03:24.44]to magnify distant objects in the background.
[03:28.96]Hubble has observed the light from galaxies
[03:33.68]that date to about 400 years after the Big Bang.
[03:39.20]But individual stars at such great distances
[03:43.80]are not possible to identify.
[03:47.40]“Usually they’re all smooshed together,”
[03:51.00]said NASA astrophysicist Jane Rigby,
[03:55.56]who took part in the study.
[03:58.76]She said, “Here, nature has given us this one star
[04:04.40]— highly, highly magnified, magnified by factors of thousands
[04:10.04]— so that we can study it.”
[04:13.24]“It’s such a gift really from the universe,” Rigby added.
[04:19.72]Welch said that Earendel may have been the main star
[04:25.00]in a two-star system, or possibly even a triple- or quadruple-star system.
[04:33.12]He noted that there is a small chance it could be a black hole.
[04:38.80]But he added that observations gathered in 2016
[04:44.12]and 2019 suggest that is not the case.
[04:49.08]The researchers said NASA’s James Webb telescope
[04:54.76]should help them learn more about the star and its parent galaxy.
[05:00.72]The Webb telescope is 100 times more powerful than Hubble.
[05:07.96]Rigby said that by studying stars:
[05:11.84]“We are literally understanding where we came from
[05:16.16]because we’re made up of some of that stardust.”
[05:20.48]I’m Bryan Lynn.
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