Star composition and elements present in a planetary system
Brooklyn Red Leg wrote:
I think I originally posted this question to the wrong group
forum...so I'll try again.
This sounds like a "worldbuilding" type of question - you might
want to try rec.arts.sf.science (unmoderated, but good signal-to-noise
ratio).
When are star has a larger percentage of heavier than helium
elements....does that necessarily translate into celestial bodies
caught in its gravity containing a higher than average chance of being
composed of what we might call strategic resource elements (aluminum,
magnesium, titanium, iron, etc)?
Short answer, no. The "terrestrial" planet like Earth are composed
of a very small, refined portion of the original solar nebula. Yes,
the nebula (that the planets form out of) of a high-metalicity star
would have a higher percentage of elements heavier than H & He, but
that just means more material to make planets out of - you might get
bigger planets, or more planets, but not more "strategic resource
rich" planets.
Furthermore, what we call "strategic minerals" are not at all
uncommon. Iron is very common, as is nickel. Aluminium is all over the
place. So why are they "strategic"? Because they're not accessible -
the iron & nickel ended up in the core, inaccessible, while things
like aluminum & titanium are present in the crust, but in oxidized
form.
For example, Barnard's Star (from what Ive read) has somewhere between
10 and 32 percent of its mass as being elements heavier than hydrogen
whereas our own star has only a fraction of a percent of its mass as
"metallicity".
Hmm... According to the references I have onhand, the metalicity of
Barnard's Star is 20% of *solar* metalicity - in other words, it has
1/5th the "metals" (elements heavier than H & He) that our own Sun
does. There are stars that have higher than solar metalicities - Alpha
Centauri, for instance, has 165% of solar metalicity, or 65% richer in
"metals" than our Sun.
--
Brian Davis
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