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Questions tagged [metallicity]

In astronomy, metallicity is a measure of how much of an object is made of elements besides hydrogen and helium.

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How many times has the matter in our Solar System been recycled from previous stars?

I've got a basic understanding of these facts: The Universe is a little over 13 billion years old. Our Galaxy is almost that old. Our Solar System is roughly 4.6 billion years old. The heavier elements (carbon, oxygen, etc...) are only produced by…
Clinton Pierce
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Metal-rich star formation

While discussing star formation on cosmological scales with some classmates, we mentioned the breakdown between the different stellar populations via metallicity: Population III: $Z = [{\rm Fe/H}] \lesssim -5$ Population II: $Z = [{\rm Fe/H}] \sim…
Kyle Kanos
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Why the distribution of elements on Earth?

I've been wondering exactly why the elements are distributed the way they are on Earth. The heavier elements have their origins in the centers of stars, or in supernovae. After the death of the stars, you end up with a dust cloud containing the…
arsenm
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Can elements heavier than iron be present in a star's core?

My understanding is that elements heavier than iron and nickel are not formed in a star but, can heavy elements such as lead and others be present/found in a star's core ? I ask because the following document…
ScienceAmateur
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When will hydrogen no longer be the most abundant nucleus?

In a recent question, we learned why hydrogen is currently the most abundant nucleon or element in the universe. Here I ask a follow-up: For how long will hydrogen be the most abundant nucleus? It is most abundant now, but is slowly being consumed…
Curt F.
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Would the emission lines of a very distant galaxy show not many traces of heavier elements as that part of the universe was very young?

Would the emission lines of a very distant galaxy show not many traces of heavier elements as that part of universe was very young? Or was there enough time for an abundance of heavier elements?
Krešimir Bradvica
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Why is the Sun made of light elements only?

Since the entire solar system inherits its heavy elements from supernovae unrelated to our star, I fail to understand why, while capturing most of said system's matter, the sun only contain light elements, especially hydrogen, selecting out heavy…
Winston
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Age of the Earth and the star that preceded the Sun

One of the great unheralded advances made in the history of science was the ability to determine the age of Earth based on the decay of isotopic uranium. Based on the apparent abundance of uranium in the early Earth, what conclusions can be drawn…
Humble
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Why are stars made from hydrogen and helium and not other elements?

My understanding is that the stars are primarily made up of hydrogen and helium. Why do those elements end up in stars and other heavier elements make up the planets?
Padraig
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Why do astronomers call all elements heavier than helium "metals"?

I understand that a scientific term need not be constrained by its etymology. But is there some significant reason why astronomers choose to call all elements heavier than helium "metals"? Are metals (in the chemist's sense) commonly easier to…
Colin McLarty
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Storing a Planet-sized Chunk of Metal Inside a Star

Would it be physically possible to "store" a planet-size or larger sum of metal, say gold or platinum, inside a star by letting it fall to the core? Would it be possible to detect which stars had these treasures inside them? (This is for a Sci-Fi…
Sam Washburn
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How to explain the existence of heavier elements in Population I stars and in Population II stars contain lighter one

Recently I read Astrophysics Notes where I found a statement that young stars are classified as Population I stars and relatively older one as Population II stars. Population I stars contain heavier elements or "Metals" - that means elements…
Radha Krishna
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Why does the Sun have iron?

I read the information about 'Abundance in the Sun for the elements'. There are a lot of elements in the Sun. I thought 'how is it possible for Fe, Au, and so on to exist in the Sun ?', but I couldn't get an appropriate answer. There are two answers…
정우남
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Stellar Activity Cycle versus Metallicity

Our Sun exhibits sunspot max/mins on about a 11 year period. It's a G2 spectral class on the HR Diagram. We know that some stars exhibit "starspot" cycles of various intensities and periods. These cycles are the result of changing magnetic activity…
Michael Luciuk
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Could quasars produce elements heavier than oxygen?

I have read that supernovae are the main producers of elements heavier than oxygen. I just wonder whether quasars, which have been around a long time just like supernovae have, could have had a comparable material effect on the universe. With all…
Richard Peterson
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