The chemical composition of these rare stars allows for new insights into the events that were supposed to lead to the birth of these stars. It is believed that the first stars were massive and shone with an extremely bright light. However, at least these observations indicate that unknown events in the early universe made possible the appearance of such small stars.
Astronomers have discovered three "Methuselah stars" - stars that were formed in the early years of the universe. These unusual stars are 13 billion years old and experts classify them as members of the first generation of stars after the Dark Age - the time when the universe was still opaque to light. This period lasted about 400 million years.
The chemical composition of these rare stars allows for new insights into the events that were supposed to lead to the birth of these stars. It is believed that the first stars were massive and shone with an extremely bright light. However, at least these observations indicate that unknown events in the early universe made possible the appearance of such small stars.
Artist's illustration of the first stars in the universe: It is believed that the first stars were massive and shone with extremely bright light. However, at least these observations indicate that unknown events in the early universe made possible the appearance of such small stars. Figure: Scientific staff members of the WMAP Space Telescope at NASA.
An international team of scientists including researchers from the Center for Astronomy at the University of Heidelberg discovered these stars.
The universe was created about 13.8 billion years ago in the big bang. The extremely hot initial gas of the "explosion cloud" spread and grew and in the process cooled. At this time the universe was empty of stars. The scientists talk about the "dark age" of the universe. About 400 million years after the big bang, the first stars were formed from the gas cloud created by the bang. Due to the chemical composition of the primordial gas which contained mostly hydrogen helium and traces of lithium, the first stars had to be 10 to 100 times more massive than the Sun, and therefore they had to shine brightly. They also quickly ran out of their nuclear fuel so they only lived a few million years. They then disintegrated in large supernova explosions. The heavier elements created in the explosion returned to the gas clouds and enriched the second generation of stars. Research that will reveal the exact chemical composition of the chemical composition of the second generation stars can allow conclusions to be drawn about the properties of the first stars.
The three stars were discovered thanks to observations at the observatory in Paris. Besides hydrogen and helium they contain very small amounts of other chemical elements, mainly respectable amounts of carbon. Astronomer Paolo Molaro of the Trieste Observatory therefore suspects that they belong to a new type of primordial stars. The Southern European Observatory in Chile has been upgraded to allow it to determine the composition of the elements with great precision. The scientists then used simulations of stellar atmospheres.
Dr. Ralf Klassen from the Institute of Theoretical Physics in Heidelberg says that carbon played an important role in the early universe as a contributing factor to the cooling of the interstellar gas and the formation of stars as a result. The better the cooling, the smaller stars can form. However, even with carbon, these stars still had masses 10 times greater than those of the new candidates. "It is possible that the interstellar dust was the cooling contributor to the formation of these light stars. We are now going to investigate this in depth" said Prof. Clasen.
According to him, the new discoveries allow interesting insights into the events surrounding the appearance of the first stars and, among other things, that it is likely that the first stars were not formed individually but in groups. The more massive stars exploded after a few million years but with much less power than previously thought. Explain the scientists from Heidelberg: "Only then could the lighter elements such as carbon or oxygen spread further into the universe and be captured by the new stars, which had a much smaller mass but a longer lifespan.
However, there is another important issue: these three stars do not even contain traces of lithium, even though this element was in the original gas cloud. According to the researchers, this is another mystery waiting to be revealed.
For the announcement of the researchers on the Heidelberg University website
More of the topic in Hayadan:
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Perhaps Avi Blizovsky will clarify the problem - what is the speed of the universe's expansion? After all, if we now see stars whose light started shortly after the big bang, when the universe was very small, then our sphere, or what it was made of then, is quite close to those stars. If, after all, it took their light so long - 13.2 billion years - to reach us, it means that we moved away from the light they sent towards us at a speed quite close to the speed of light.
Assuming that at the same time the distance of the stars from the place where the material that later created the earth was 0.4 billion light years and the distance in the time it took for light to reach the earth is 13.2 (13.6-0.4) billion light years then the expansion speed of the universe where we are should be: 0.97 C = C*(1-0.4/13.2)
is it true?
The star HD 140283 is 14.5 billion years old.
A universe less than 13.8 billion years old.
I'm not talking about the amount of stars we haven't discovered yet. And according to probability there should be many more of them...
What's for sure, for sure someone made a big mistake here
When taking rides you have to be careful not to get caught up in a violent super nova event or fall into a black hole
People of the Book
I personally prefer less violent books. "The Hitchhiker's Guide to the Galaxy" is much more endearing.
I know a lot of snakes that talk non-stop
There are many stories there.
A little history.
A lot of parables.
Even songs..
You know…. The best book ever. which includes everything from everything.
Over belts
Isn't this the same story as "Darkness over the Abyss"?
Ahhh, no... sure... yes... but it's a parable... What, you haven't studied or don't know that book? 🙂
Over belts
I thought it was written in that book….
Miracles
you live in a fantasy. There is no such thing as a talking snake.
There are not enough articles in astrology
Over belts
And what about the talking snake? Will science discover this too? 🙂
"The universe was sealed off to light"... Darkness over an abyss.
Then there will be light... and Saturday... blah blah blah…….
Sages knew this a long time ago.
Science and scientific tools only establish this idea as fact.
to Elisef
The universe is accelerating (at least it seems that way), that's why there are stars that we will never see because the speed of light is constant..
for everyone,
1. Nowhere in the article does it say that the light from those stars made its way to us for 13 billion years, but that the age of the stars is 13 billion years.
2. The universe is expanding at a speed higher than the speed of light.
Chen T
I agree that today it is impossible to know much about them (in fact, the article says that they existed for a short time and exploded a long time ago)
But finally the light traveled 13 billion light years, and if it reached us now, it means that we moved away from the light source a similar distance, it follows that the moving away was at a speed close to the speed of light. And that's regardless of what's happening there now.
In other words:
The light traveled 13 billion light years
Earth has also traveled 13 billion light years
(The 400 million years that were before must be added, but the change is not great)
Eliasaf
The light reached us 13 billion years after it left these stars, this does not mean that they are now 13 billion years away from us, but that they were at that distance when the light left them. Because the universe is expanding, if you were to draw a line from Earth back to them you would not reach their current location, and there is no idea if they still exist
A question that has been bothering me for a long time:
The universe was created 13.8 billion years ago, which means that at that time all the mass in the world was concentrated in one point. That is, the distance between the particles that today make up the solar system, and those of these stars was 0.
400 million years later, those stars, the Euro and their light headed our way.
For 13 billion years the light made its way that was observed in telescopes on Earth
The distance between us and these stars today is 13 billion light years.
Now the question is: how is it that the universe expanded 13 billion light-years in a similar amount of time, that light traveled this distance? Is the universe expanding at the speed of light? (Even if we take into account the expansion of the universe in the first 400 million years, the universe is still expanding at a speed of 90% of the speed of light, which does not seem logical)