Questions tagged [metal]
Any element other than hydrogen and helium is considered a metal by astronomers.
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Is lithium considered a metal in astronomy?
My lecture notes are conflicting on this issue so I seek definitive clarification. In Astronomy, are metals either
A: the elements which form within stars (i.e., not Big Bang nucleosynthesis, where ...
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Why can't a quasistar exist now?
From my research, I found out that quasistars theoretically existed because of a black hole core whose radiation pressure counteracted gravity within the star. However, a few websites stated that ...
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Why you use log to measure metallicity in galaxies?
For example, I saw the next expression for matallicity in a paper: $\log(O/H) + 12$.
I understand O/H is the O(Oxygen) to H(Hydrogen) ratio but why is there the number 12? And why the logarithm?
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What are the most valuable meteorites and asteroids in terms of precious metals?
There were some suggestions that asteroids could one day be mined for precious metals. I have found an outdated study that says that some siderites contain as much as 0.001% of gold:
http://pubs.usgs....
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What is the reason for the dispute over the variation of core mass with heavy metal abundance?
In Metal-Poor Stars IV: The Evolution of Red Giants, Rood writes
The differences in the results of these papers are large enough to introduce appreciable uncertainties into the study of the ...
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Metal distribution in our solar system
The sun dominates in our solar system.
I wonder whether in every aspect the sun plays the most important role in our system.
For example, all kinds of metals are mainly located in the sun instead of ...
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Why could Quasi-stars ("black hole stars") have only existed when everything was hydrogen and helium? (no metal "contamination")
This informative answer to What was the absolute limit to the possible sizes of the first stars formed from “primordial material with no metals”? led me to Wikipedia's Quasi-star; Formation and ...
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Why are stars more metallic closer as you move closer to the galactic bulge?
As I see it, most of the stars in the galactic bulge are Population I stars. However, as one moves farther from the galactic bulge, star metallicity decreases. In fact, halo stars are almost entirely ...
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Is metallicity low at the central region or nucleus of the Milky Way?
Is metallicity low at the central region or nucleus of the Milky Way? Does metallicity decrease or increase as we move from the center out to the edges of our galaxy?
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Does Gold really come from Supernovas? [duplicate]
Do we really know that the origin of gold was in a supernova explosion?
I am talking about the gold we find here on Earth.
So then how are we sure that Gold actually came from these explosions. Did ...
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What happens to the non-fusion formed metals in stars?
Let’s consider a population I star of some given metallicity.
I know that depending on the type of star, different structures are possible with convection zones and radiative zones trading around ...
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How do astronomers detect the 'metals' in a star? If the atoms are presumably completely ionized?
Atoms and molecules usually emit their characteristic wavelengths because of the electrons' energy levels....
Do the completely ionized ('naked') nuclei absorb and/or emit EM radiation?
If so, at what ...
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What is the etymology of the astronomical term metal [duplicate]
It's well known that Astronomers use the term "metal" to describe any element heavier than Helium but could anyone tell me why? What is the history of this particularly strange bit of language?
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If two pieces of the same type of metal touch in outer space, they will bond together permanently? [closed]
Is this true? And if so, why?
http://www.snapple.com/real-facts/cap-view/1003
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Why is the carbon/oxygen ratio at low metallicities important to study?
Oxygen and carbon are the most abundant elements in the Universe (formed via stellar nucleosynthesis), following only hydrogen and helium (formed via the Big Bang). There seems to be a lot of work to ...
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Where/how are metals distributed in our universe?
For one particular kind of element, what is the distribution in the whole universe?
Are most of the metals located in ISM, IGM, or stars? Maybe different metals have different distributions?
For ...
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