Tuesday , April 20 2021

The star revealed with origin near the Big Bang



Astronomers discovered what could be one of the eldest stars in the universe, 13.5 billion years old, almost entirely of material that had been thrown out of the Big Bang.

The discovery of a small star means probably bigger stars with very small mass and very low metal content – perhaps even some of the first stars of the universe.

The star is unusual because, unlike other stars with very low content of metal, it is part of the "thin disc" of the Milky Way – part of the galaxy in which our own Sun is located.

Researchers said it is possible that our galactic district is at least 3 billion years older than we thought.

"This star is perhaps one in 10 million, and it tells us something very important for the first generation of stars," said chief author Kevin Schlaufman, assistant professor at Johns Hopkins University in the United States.

The first stars of the universe after the Big Bang would consist solely of elements such as hydrogen, helium and small amounts of lithium.

The stars then produced elements heavier than helium in their cores and they planted the universe when they exploded as supernova.

The next generation of stars came from the clouds of material that were glued to these metals, including in their make-up. The metal content, or metallic stars of the universe, increased as the cycle of birth and death of a star.

The newly discovered star system orbits the galaxy to a circular orbit that, like the orbits of the sun, never goes far beyond the plane of the galaxy.

On the other hand, most stars of extremely metallic stars have orbits that take them all over the galaxy and far from their plane.

The exceptionally low metallicity of newly discovered stars suggests that only one generation of the Big Bang could be found in the cosmic nursery tree.

Indeed, it is a new star-track holder with the smallest addition of heavy elements – it has roughly the same content of heavy elements as the planet Mercury.

By contrast, our Sun thousands of generations fall down this line and have the content of heavy elements equal to 14 Jupiter.

The star is part of a two star system that circles around the common point.

As recently as the late 1990s, scientists believed that only the massive stars could form in the earliest stages of the universe – and they could never be watched because they burned fuel and died so fast.

However, as astronomical simulations became sophisticated, they began to suggest that in some situations the stars from that low-volume period may still exist, even more than 13 billion years from the Great Burst.

Unlike big stars, those small masks can live for a very long time. For example, the red dwarf star, with a fraction of the mass of the Sun, is thought to live up to trillion years.

The discovery of this new ultra-metal star, dubbed 2MASS J18082002-5104378 B, opens up the possibility of observing even older stars.

"If our conclusion is correct, then there may be low-mass stars that have the composition solely for the Big Bang," Schlaufman said.

"Although we have not found such an object yet in our galaxy, it may exist," he said.

(This story has not been edited by standard business staff and is automatically generated from a syndicated feed.)


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