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Scientists have discovered the farthest and oldest star – it is almost the same age as the universe

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Photo author, NASA

Caption to the photo,

This little muddy point in the photo is the mysterious Erendel

Nearly 13 billion light-years, the distance is amazing even for a watchful telescope like the Hubble. Usually from this distance, its optics can only see large galaxies, each with millions of stars. And yet NASA’s Space Observatory has managed to view the ancient star Earendel on the edge of the universe – thanks to a physical phenomenon predicted by the theory of relativity.

When the light of a distant star “bumps” on its way to a massive (by cosmic standards) object – such as a neutron star or a cluster of galaxies – the gravitational field created by this object distorts the space around it, changing the trajectory of light rays , which as a result are bypassed, while receiving additional momentum.

In science, this phenomenon is known as “gravitational lensing”, because the massive body acts here as a lens, amplifying light rays.

Usually, scientists use this method to discover distant galaxies, but in this case, a single star was lucky: its light rays were amplified so much that it hit the telescope.

“We were just unbelievably lucky,” said Brian Welch, astrophysicist and astrophysicist at Johns Hopkins University in Maryland, in an interview with the BBC.

The previous distance record belonged to a star called ICAR. It was also found by Hubble – at a distance of “only” 9 billion light years from Earth.

Erendel is much further away, and we observe the star at a time when some 900 million years have passed since the Big Bang, and the universe was in its infancy.

By the way, the name of the star Erendel (actually officially it is not so romantic – WHL0137-LS) is not associated with the magical kingdom of Erendel from the Disney cartoon “Cold Heart”, but comes from the Old English word meaning “morning star”. And in the Hubble picture, it’s more of a dim spot.

Another thing is that in the eyes of the astronomers who discovered it, Erendel looks completely different. However, they willingly admit that they still know little about this star. They can’t even say for sure what size it is: it is clear that it is at least 50 times larger than our Sun, one of the largest stars ever found, but it may be that it is actually much larger, 500 times!

It is also possible that Hubble detected the so-called binary star, ie essentially two stars whose orbits are located close to each other. This is a very common phenomenon, but in this case one of the stars must be significantly more massive than the other, and it is its light signal will be dominant.

There is, however, an alternative explanation: Erendel is not really a distant star, the light from which was refracted and intensified, passing by a cluster of galaxies, and an object in the foreground with star-like light handwriting, such as a brown dwarf. However, this is unlikely, because after 5 years of observations, the object remained static, while located much closer than the dwarf should have moved slightly in space.

One of the most interesting mysteries is the composition of the new-old star. Astronomers have reason to believe that Erendel is one of the primary stars formed from the primordial gas created by the Big Bang.

The theory is that the first stars consisted only of hydrogen and helium, but this meant that they burned out quickly, over millions of years, and then collapsed. And only after the stars “lived” with heavy elements, outer space began to look like we are used to.

But if Erendel is indeed the original star, it could only last 900 million years after the Big Bang if it formed from an isolated, undiluted cloud of gas – and this, though possible, is still very unlikely.

Photo author, NASA

Caption to the photo,

Hubble has been in orbit since 1990 and continues to make amazing discoveries.

“We suspect that Erendel was probably a little rich in heavy elements, but not as much as the stars around us today,” Welch said. [к гипотетическому населению III принято относить первое после Большого взрыва поколение тяжелых звезд, которые, опять же в теории, не дожили до наших времен]. According to some theories, such stars can still be found on the outskirts of some galaxies.

If astronomers are destined to find such stars, the successor to Hubble, the James Webb Space Telescope, launched last December and equipped with more advanced equipment, will be able to do so.

James Webb will be fully operational in a couple of months, and Brian Welch and colleagues have already set aside time to work with the new space observatory to take a closer look at Erendel.

By the way, no one is going to write off Hubble’s old man. Although it was launched back in 1990 and partly obsolete, this telescope continues to help scientists make great discoveries.

“Hubble Telescope feels great,” said NASA staffer Dr. Jennifer Weissman. “It’s powerful, it has high scientific performance, and we hope that Hubble will make many more discoveries in the future. will work in parallel with “James Webb”. With these two telescopes at hand, we will be able to learn about the universe much more than we have managed so far. “

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